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Eric
10-03-2009, 05:52 PM
Originally Posted by REM :

"I have a 2003 Passat GLS with the 1.8T engine and an A/T. Lately the A/T is acting up. When I slow to a stop, the engine stumbles and then catches itself. It's very similar to what happens when you have a manual trans and wait too long to let out the clutch when you're slowing to a stop. Also, I've observed some slipping in various situations such as downshifting or sudden acceleration. When it downshifts, it sometimes bangs into the lower gear. The car has only 74,000 miles and has had pretty gentle use.


Would it make sense to first try flushing and replacing the fluid and strainer. VW, I believe, says the fluid doesn't need to be changed. It's there for life, they say. I'm not sure I buy that.

What should it cost for a flush, filter replacement, and pan cleaning? I called the local VW dealer and asked them about this and they acted like there was something wrong with me for asking this.


Any other ideas? Thank you."


Hi REM,

In most cars equipped with automatic transmissions, it's routine service to periodically drain the fluid and replace the filter - because filters do get clogged over time with the small particles that wear off internal friction clutches and so on - and because the fluid gets contaminated and/or its additive package loses potency, etc.

I'm surprised to learn that VW consider it unnecessary to ever change either the fluid or the filter - and that the dealer's treating you like you're crazy for asking about it. Maybe VW has developed a transmission that does not wear internally and thus its internal filters never get clogged? (In which case, why even have a filter at all?) And I have never heard of any oil or hydraulic fluid that never deteriorates.

Have you?

Given 70,000-plus miles without a change of either the fluid or the filter, I would not be surprised to find trouble such as you describe. Automatic transmissions (as you probably know) transmit engine power hydraulically, through a torque converter and valve body. The valve body has many small passages in it. Even a very small bit of debris lodged in one of these passages can affect the transmission's functions significantly. Varnishes can make internal valves/accumulators, etc. sticky - which results in weird shift quality and so on.

I hope it is not permanent damage and would recommend as a first step, that the old fluid and filter be changed.

Bottom line, changing out the fluid/filter is not going to hurt anything, is almost certainly necessary (given the mileage) and may just fix your problem. Be sure to use the exact type of fluid recommended by VW, though - and filter, too. Some brands of cars are very sensitive to the type of fluid used and use of the wrong type brand can lead to premature and very expensive failures. etc.

I would look at this as routine maintenance, no matter what VW or the dealer tells you.

Now, if the problem persists, there may be a bad sensor (modern automatics are electronically governed) or some other external issue. A good repair shop (not necessarily your VW dealer) ought to be able to track that down if necessary. But changing the transmission's fluid/filter is essential (in my opinion) at this mileage, regardless of other possible problems.

dBrong
10-03-2009, 06:35 PM
If you do drop the pan - keep the pieces (hopefully not) that are in the pan. A good transmission guy can look at the pieces in the pan - and maybe tell you the condition of your tranny - or what is failing.

REM
10-03-2009, 07:08 PM
In most cars equipped with automatic transmissions, it's routine service to periodically drain the fluid and replace the filter - because filters do get clogged over time with the small particles that wear off internal friction clutches and so on - and because the fluid gets contaminated and/or its additive package loses potency, etc.

I'm surprised to learn that VW consider it unnecessary to ever change either the fluid or the filter

. . .

I hope it is not permanent damage and would recommend as a first step, that the old fluid and filter be changed.

Bottom line, changing out the fluid/filter is not going to hurt anything, is almost certainly necessary (given the mileage) and may just fix your problem. Be sure to use the exact type of fluid recommended by VW, though - and filter, too. Some brands of cars are very sensitive to the type of fluid used and use of the wrong type brand can lead to premature and very expensive failures. etc.

I would look at this as routine maintenance, no matter what VW or the dealer tells you.



Thanks for that reply Eric. Yes, believe it or not, VW claims they have a sealed system for life. I've heard others comment that what VW is not telling you is that "life" means 60k - 90k miles if you follow their guidelines. Recommended factory service is just to check the levels and top off if necessary at 40k intervals. Pretty unbelievable, if you ask me.

Do I need to actually do a "flush" where they run fresh fluid through the lines until the new fluid comes out the other end? Or is a drain and replace, together with a filter change and pan cleaning enough? What should this cost?

Any opinions about AAMCO or Lee Myles?

Eric
10-03-2009, 07:51 PM
Thanks for that reply Eric. Yes, believe it or not, VW claims they have a sealed system for life. I've heard others comment that what VW is not telling you is that "life" means 60k - 90k miles if you follow their guidelines. Recommended factory service is just to check the levels and top off if necessary at 40k intervals. Pretty unbelievable, if you ask me.

Do I need to actually do a "flush" where they run fresh fluid through the lines until the new fluid comes out the other end? Or is a drain and replace, together with a filter change and pan cleaning enough? What should this cost?

Any opinions about AAMCO or Lee Myles?

No problem!

And yes, I agree with you that VW's definition of "life" is absurd. It's asking for premature (and expensive) transmission problems, in my opinion.

A flush is better than just draining the pan as the flush will remove all the old fluid and replace it with fresh fluid while just draining the pan will only remove about 1/2 of the total volume.

The main thing to worry about is that whomever you get to do the service knows what they are doing - and that they use only the fluid listed by VW (as well as the correct filter).

Use of the wrong type of fluid can lead to rapid failure and will also kill your warranty (if that's still in effect).

AAMCO and so on are franchised/chain stores; some are better than others. Before you take your car there, check with the local Better Business Bureau to see whether that shop has an unusual number of complaints; also ask friends and people you trust for recommendations. You probably know someone who knows a "good shop."

Keep us posted - I'm hoping the flush/fill/filter will correct the problem you've got...

MikeHalloran
10-03-2009, 10:53 PM
My 2002 Ford Explorer also has a 'sealed for life' transmission... and no dipstick.
There is instead a small standpipe, vented through the bottom of the pan.
So far, so good...

In my limited experience with ATs other than that one, a system flush that does _not_ include removing the pan does more harm than good, because there are _always_ a few chips in the pan, and the high velocity of the flush can move them to a place where they can do harm. They could rest in the bottom of the pan indefinitely and do no harm. Damage from 'professional flushes' may have driven the manufacturers to invent 'sealed for life', in my opinion.

Pulling the pan and replacing the filter and whatever comes out may help. If you do it yourself, strain the effluent and keep the chips and a sample of the fluid, so you can show it to a good transmission guy, assuming you can find one.

Before doing any of that, I'd closely inspect the wire harness for damage, and look for rot in any attached vacuum lines. (I'm not sure there _are_ any on a VW; it used to be the standard way to communicate engine load to a hydraulically controlled transmission, and the hose or the vacuum diaphragm used to be the first thing to fail, and the cheapest thing to fix.)

DonTom
10-04-2009, 01:08 AM
No problem!

And yes, I agree with you that VW's definition of "life" is absurd. It's asking for premature (and expensive) transmission problems, in my opinion.

But leaks probably won't be one of them. Often a new fresh tranny fluid change will cause leaks from cleaning out crud from the flaky gaskets that was holding the tranny fluid in.

Some people never change tranny fluid or filters and get well more than 150K miles life out of them. And often those who maintain them better don't get any more miles out of them. They sometimes only get more leaks.

I very rarely bother with a tranny fluid change in any of my vehicles, unless I notice something wrong, such as the burnt toast smell of the tranny fluid or it not looking as it should.


-Don- (back home in SSF, CA)

REM
10-04-2009, 01:15 PM
Keep us posted - I'm hoping the flush/fill/filter will correct the problem you've got...

Eric,

I just heard from a transmission expert that while the flush & filter change is important maintenance, once slipping and other problems appear, the flush & filter change rarely help.

Any further thoughts?

Eric
10-04-2009, 01:38 PM
Eric,

I just heard from a transmission expert that while the flush & filter change is important maintenance, once slipping and other problems appear, the flush & filter change rarely help.

Any further thoughts?

Well, I'm hoping for the best, but unfortunately yes, the guy you spoke with is more than likely right. Slipping is usually a bad sign. It could, however, be a maladjusted throttle valve cable or some other issue. Let's keep our fingers crossed.

Meanwhile, changing out the fluid and filter is not going to hurt, should not cost much and in any case needs to be done given the mileage, etc.

Mike had a good point, too - the pan should be dropped first (before the flush) so that any debris in the pan can be removed and inspected.

REM
10-04-2009, 02:32 PM
Mike had a good point, too - the pan should be dropped first (before the flush) so that any debris in the pan can be removed and inspected.

Absolutely. It seems insane to flush the system with all the crap sitting in the pan to just go and circulate and get trapped in the valve body or other places. The only "right" way to do this it appears is to drop the pan, power flush, change the filter, thoroughly clean the pan, inspect the particles, replace the pan and top it off.

If my tranny needs a rebuild, I may just trade the car in. Do you know what a rebuild (or swap with a rebuilt) cost? The car's only worth about $7,000.

dBrong
10-04-2009, 04:30 PM
The problem is that you may not be able to sell the car, without paying the cost of replacing the transmission. I would guess a rebuild would be $2500. If you could swap it with a used one, might be a better way to go, and keep driving the car.

Eric
10-04-2009, 05:53 PM
Absolutely. It seems insane to flush the system with all the crap sitting in the pan to just go and circulate and get trapped in the valve body or other places. The only "right" way to do this it appears is to drop the pan, power flush, change the filter, thoroughly clean the pan, inspect the particles, replace the pan and top it off.

If my tranny needs a rebuild, I may just trade the car in. Do you know what a rebuild (or swap with a rebuilt) cost? The car's only worth about $7,000.

You've got a real Catch 22 situation there if the tranny needs rebuilding/replacing. The cost is probably going to be in the neighborhood of $2,000 for a new/rebuilt unit (parts and labor). But your car will be worth the same after it's fixed (no increase in value, or not much). On the other hand, if you try to sell it with an obviously failing transmission, you won't get much for it. You'll lose about what it would cost to have it fixed, probably.

But let's not get ahead of ourselves just yet. First thing to do is drop the pan and have a look. If you don't find pieces of debris (just some light gray/gritty stuff - which is normal wear and tear) you may not have a major problem. Replace the filter/fluid and see how it drives. If the problem is still there, I'd suspect some electrical/sensor-related issue that may be a fairly easy and cheap fix.

Keep us posted!

chiph
10-04-2009, 06:35 PM
Be cautious about doing a flush -- sometimes the internal filter gets damaged due to overpressure.

I would recommend two drain & fills, with you driving about 100 city miles between them.

Chip H.

REM
10-04-2009, 08:37 PM
Be cautious about doing a flush -- sometimes the internal filter gets damaged due to overpressure.

I would recommend two drain & fills, with you driving about 100 city miles between them.

Can you do a flush with the filter removed? (Something tells me "no") Does it matter if the filter gets damaged since you're changing it anyway?

Two drains and fills are an interesting idea. You'll still have some dirty fluid in there, but not a lot. It will be about 75% new, 25% old, assuming that only half the fluid in the box comes out when you drain.

Eric
10-05-2009, 08:18 AM
Can you do a flush with the filter removed? (Something tells me "no") Does it matter if the filter gets damaged since you're changing it anyway?

Two drains and fills are an interesting idea. You'll still have some dirty fluid in there, but not a lot. It will be about 75% new, 25% old, assuming that only half the fluid in the box comes out when you drain.

I agree with Chip. I would be overcautious and do this job myself in the following way:

Raise the car, drop the pan/drain the fluid - clean the pan/remove filter. Install new filter, top off transmission with fresh fluid. With the front wheels raised and the car properly chocked/supported, etc., start the car and put the transmission in each range. Run the transmission briefly in each range. Stop the engine, let it cool, then drop the pan/drain the fluid again. Check the filter and replace if need be. Refill and then drive the car.

Before you start this job, I recommend buying a drain plug kit from a place like Summit Racing or JEGS. (Assuming your VW's pan does not have a drain plug already, of course!) This will make future service a lot less messy and a whole lot easier. Installing the plug is extremely simple; anyone who can operate a drill can do it.

If you prefer not to do this yourself, find a shop that will do it for you, as per the above. Don't let them talk you into the power flush thing unless they have first removed the pan/cleaned it and removed/replaced the filter.

If you find a lot of debris (pieces of shredded metal, etc.) and not just some fine particle sludge, the tranny is probably toast and replacing the fluid/filter is probably not going to do much for you.

REM
10-06-2009, 08:22 PM
Eric,

I'm bringing it into the local AAMCO on Thursday. I spoke on the phone to the mgr there, and they seem to do things the right way. He said if there's evidence of an internal problem, he would NOT flush the tranny, because that would make things worse. He said if there is an internal problem, flushing or even a fluid change is a waste of money. But he also said there's a 50-50 chance that it just might be an electric/electronic problem.

And I forgot to mention. My Ck Engine light has been on for awhile. It was related to one code for a bad thermostat that I haven't yet changed. But for all I know, a couple of more codes could have popped up too. The light doesn't get brighter when more codes pop up. :)

Eric
10-07-2009, 07:40 AM
Eric,

I'm bringing it into the local AAMCO on Thursday. I spoke on the phone to the mgr there, and they seem to do things the right way. He said if there's evidence of an internal problem, he would NOT flush the tranny, because that would make things worse. He said if there is an internal problem, flushing or even a fluid change is a waste of money. But he also said there's a 50-50 chance that it just might be an electric/electronic problem.

And I forgot to mention. My Ck Engine light has been on for awhile. It was related to one code for a bad thermostat that I haven't yet changed. But for all I know, a couple of more codes could have popped up too. The light doesn't get brighter when more codes pop up. :)



Excellent!

I'm hoping it turns out to be an electronic fault of some kind. 70,000 miles is way to early for a transmission to fail unless it's been seriously abused or just happens to be a poorly built/weak unit to begin with.

I haven't heard of widespread premature problems with VW automatics (anyone else?) so with luck, you'll be back in business for the cost of a fill n' flush or a minor service/replacement of some sensor, etc.

swamprat
10-07-2009, 09:42 PM
Eric,

I'm bringing it into the local AAMCO on Thursday. I spoke on the phone to the mgr there, and they seem to do things the right way. He said if there's evidence of an internal problem, he would NOT flush the tranny, because that would make things worse. He said if there is an internal problem, flushing or even a fluid change is a waste of money. But he also said there's a 50-50 chance that it just might be an electric/electronic problem.

And I forgot to mention. My Ck Engine light has been on for awhile. It was related to one code for a bad thermostat that I haven't yet changed. But for all I know, a couple of more codes could have popped up too. The light doesn't get brighter when more codes pop up. :)

I remember way back when I had a Mercury Cougar, the transmission had extreme difficulty shifting. It would start in second and would not go into overdrive. It turned out to be a Throttle Position Sensor. The sensor was replaced and that solved the problem.

dom
10-07-2009, 11:17 PM
Sounds to me that your tranny has multiple issues.

1) the stumbling when slowing down sounds like a sticking torque converter lockup switch

2) the slipping could be worn clutch discs, or incomplete engagement because of stuck valves from debris, or just some bad solenoids or wire connections in there.

3) all this stuff easily could be some messed up electrics, or an internally filthy tranny.

I can't believe VW says not to change the fluid for the life of the tranny. That is insane!

Eric
10-08-2009, 07:43 AM
"I can't believe VW says not to change the fluid for the life of the tranny. That is insane!"

I can. Reason? Marketing. Why, just look at our fine cars! They never need routine service!

Which sounds good up front, which is all that matters (apparently).

Down the road, though, it's a different story.

VW is not the only sinner here. See also:

Lifetime coolant
100,000 mile spark plugs

Etc.

REM
10-10-2009, 11:40 PM
Excellent!

I'm hoping it turns out to be an electronic fault of some kind. 70,000 miles is way to early for a transmission to fail unless it's been seriously abused or just happens to be a poorly built/weak unit to begin with.

I haven't heard of widespread premature problems with VW automatics (anyone else?) so with luck, you'll be back in business for the cost of a fill n' flush or a minor service/replacement of some sensor, etc.

I had the car in to AAMCO. They told me the car is showing Codes 17114 / PO 0730. They said fluid level is good, and color is starting to turn. Surprisingly, they stated that they didn't get a code for a bad thermostat that was showing up consistently for the last several months, and the thermostat problem is still there. They said the problem is definitely internal damage, and the tranny will have to be removed disassembled and inspected. Cost = $1,172.50, but that doesn't include any repairs, which he said could be anywhere from $2,000 to $5,000. (If the repairs are done, the $1,172 is credited against the cost).

They also said that the tranny was stuck in 3rd gear during the test drive and all the indicator lights came on. This is something I NEVER observed. There was a lot of high pressure sales tactics and warning me that I could get stranded without warning. They also didn't have any written printout to give me claiming that it's all on the computer and can't print out. Frankly, I was skeptical of their diagnosis.

I've been reading up on Code 17114 and it appears that it's a generic code that doesn't really pinpoint the problem. How do I even know if the car generated those codes? Does the VAG-COM print out a report?

Time for a second opinion, I think.

Any other thoughts?

REM
10-10-2009, 11:46 PM
Dom,


Sounds to me that your tranny has multiple issues.

1) the stumbling when slowing down sounds like a sticking torque converter lockup switch

2) the slipping could be worn clutch discs, or incomplete engagement because of stuck valves from debris, or just some bad solenoids or wire connections in there.

3) all this stuff easily could be some messed up electrics, or an internally filthy tranny.

I can't believe VW says not to change the fluid for the life of the tranny. That is insane!

Thanks for the reply. Had it in to a tranny shop and they said the fluid level was good and the color was "starting to turn". So it doesn't sound like it was filthy. Sounds like you're saying that a flush might be worth the investment.

Which specific "messed up electrics" are the prime suspects? Are the ones you mentioned all internal?

As far as VW's "lifetime sealed unit", what they're not telling you is that if you follow their instructions, "lifetime" will be 60-90k.

Eric
10-11-2009, 08:06 AM
Dom,



Thanks for the reply. Had it in to a tranny shop and they said the fluid level was good and the color was "starting to turn". So it doesn't sound like it was filthy. Sounds like you're saying that a flush might be worth the investment.

Which specific "messed up electrics" are the prime suspects? Are the ones you mentioned all internal?

As far as VW's "lifetime sealed unit", what they're not telling you is that if you follow their instructions, "lifetime" will be 60-90k.

Many modern automatics have (among other electronically controlled functions), a torque converter lock-up switch and a throttle valve switch that governs up and down shifts, based on engine load, etc. A fault with either of these could produce some of the symptoms you're experiencing.

I'd still want to have a look inside the pan (and have the old filter out and replaced) regardless, given the mileage, etc.

REM
10-11-2009, 07:19 PM
Many modern automatics have (among other electronically controlled functions), a torque converter lock-up switch and a throttle valve switch that governs up and down shifts, based on engine load, etc. A fault with either of these could produce some of the symptoms you're experiencing.

Are those switches internal or external?



I'd still want to have a look inside the pan (and have the old filter out and replaced) regardless, given the mileage, etc.I'm thinking of doing just that. I need to find a mechanic who knows transmissions that I can trust who can look at the particles in the pan and give me an honest evaluation.

Eric
10-12-2009, 07:42 AM
"Are those switches internal or external? "

I'm not familiar enough with late model VWs to say; Dom? Any of you guys know?

"I'm thinking of doing just that. I need to find a mechanic who knows transmissions that I can trust who can look at the particles in the pan and give me an honest evaluation."

A question: Do you do your own oil changes? If yes, this is something you could probably do on your own. The main difference is that the transmission pan, unlike the oil pan, probably does not have a drain plug. (The manufacturers stopped providing them, allegedly to encourage people to remove the pan so as to get the old filter out rather than to just drain the fluid, etc. But more likely, to make DIY service more of a PITAS and thus increase dealer's profits.) This means you'll have to deal with dropping a pan that's got several quarts of messy fluid in it. But if you use a large catch pan (and dress in old clothes!) it's no big deal. If you can jack up/safely support the car, crawl underneath and using a ratchet/socket set, back out maybe a dozen bolts that hold the pan in place, this is a job you can definitely do on your own.

And, it's not necessary to be a trained expert to "read the pan." If you find more than fine, silty-looking grains of stuff (normal wear and tear) you likely have problems. Bigger stuff that looks like bits of shredded tin, any chunks of metal, etc. almost certainly means major internal problems.

dom
10-12-2009, 02:56 PM
I'm sure all the switches and electronics are internal (not 100%, but have never seen it any other way). VWs are a trick to be honest. I don't really have any experience messing with them. I know enough about VWs to know they do things a bit different.

REM
10-12-2009, 05:43 PM
I'm sure all the switches and electronics are internal (not 100%, but have never seen it any other way).

So, if they're all internal, we're still talking about a major (i.e., expensive) job of removal, disassembly, repair, and reinstall, right? Or, could you access the internal switch and other electric components while the tranny is still on the car? If not, and the tranny has to be removed, it wouldn't be much cheaper than having the tranny removed and completely rebuilt. So, tell me why I should be happy if it's "just a switch".

First thing I think I want to do is get a second opinion and see if those codes really came up.

Any further thoughts?

dom
10-12-2009, 10:13 PM
Well, just because a switch is internal doesn't mean you can't drop a trans pan, or remove an inspection plate to access them. I've changed a couple torque converter lock-up switches without removing anything more than an inspection plate on a number of occasions.

I understand your concern and attempts to discover the problem before condemning the tranny. All it takes is one bad diagnosis to turn this into a multi-thousand dollar repair. I am not saying that it's not though.

Did you say the year, engine size, model, etc of this unit?

I am going to check the previous posts for that information.

If you have not, please list it.

I will check service recalls and common issues for that particular unit this week for you.

note: I just checked and see all the info for the car. I will do some research this week in my free time at work for you.

REM
10-12-2009, 10:33 PM
Well, just because a switch is internal doesn't mean you can't drop a trans pan, or remove an inspection plate to access them. I've changed a couple torque converter lock-up switches without removing anything more than an inspection plate on a number of occasions.

That's what I was hoping you might say. Can you state, generally, whether most electrical components are, or are not, accessible without removing and opening up the tranny?



I will check service recalls and common issues for that particular unit this week for you.
note: I just checked and see all the info for the car. I will do some research this week in my free time at work for you.I appreciate that, Dom. Thank you very much.

dom
10-12-2009, 10:56 PM
I don't know shet about VWs man. Other than general maintenance, they are alien to me!

No problem on checking up on it. I will keep you posted if I find anything. In the mean time I would suggest doing some research with buddies and find a connection to a friend of a friend you can trust at a tranny shop.

REM
10-16-2009, 08:31 PM
I had the car in to AAMCO. They told me the car is showing Codes 17114 / PO 0730. They said fluid level is good, and color is starting to turn. Surprisingly, they stated that they didn't get a code for a bad thermostat that was showing up consistently for the last several months, and the thermostat problem is still there. They said the problem is definitely internal damage . . .

I've been reading up on Code 17114 and it appears that it's a generic code that doesn't really pinpoint the problem. How do I even know if the car generated those codes? Does the VAG-COM print out a report?

Time for a second opinion, I think.



The above is what I said a week ago. Well, here's the latest. I took the car to an auto parts place that does a free Code check. What they found was what I expected, and suspected. No transmission Codes at all appeared. Only the cooling system Code P2181 that I was aware of.

So again I ask: How do I even know if the car generated those bad transmission codes at AAMCO? And why didn't his check of the codes reveal the P2181 code that's been there for several months? And the fact that the guy at AAMCO gave me some b.s. reason for why he couldn't give me a printout showing the bad codes makes me even more suspicious.

So next step is to have the fluid drained/replaced or flushed, have the pan cleaned and examined, have someone check the electrics and whatever else can be checked from underneath, and see how the tranny acts.

One last thing: When I put the tranny into Sport Mode, where you shift manually, it seems to perform just fine.

Eric
10-17-2009, 09:34 AM
"One last thing: When I put the tranny into Sport Mode, where you shift manually, it seems to perform just fine."

That is a very important clue!

If a mechanical problem existed such as burned up clutches, etc,. then the transmission would slip all the time.

If it works normally in Sport mode, then the problem is probably related to the electronics.

In Sport mode, the transmission's overdrive (and lock-up converter) are typically locked out, to provide more aggressive gearing for better performance/feel.

That's where I'd begin to look.

PS: The OBD scan port (where you get the trouble codes) is located just under the steering column/dash area. If you have an OBD scanner or have a friend who has one, you can find out what codes are being churned out by your car's computer in 30 seconds with no tools (other than the scanner).

Also, if you have Advance Auto Parts in your area, they will retrieve your trouble codes (using their scanner) for free. I'm not sure, but NAPA and Pep Boys and other such stores may offer the same service....

REM
10-17-2009, 05:46 PM
"One last thing: When I put the tranny into Sport Mode, where you shift manually, it seems to perform just fine."

That is a very important clue!

If a mechanical problem existed such as burned up clutches, etc,. then the transmission would slip all the time.

If it works normally in Sport mode, then the problem is probably related to the electronics.

In Sport mode, the transmission's overdrive (and lock-up converter) are typically locked out, to provide more aggressive gearing for better performance/feel.

That's where I'd begin to look.

PS: The OBD scan port (where you get the trouble codes) is located just under the steering column/dash area. If you have an OBD scanner or have a friend who has one, you can find out what codes are being churned out by your car's computer in 30 seconds with no tools (other than the scanner).

Also, if you have Advance Auto Parts in your area, they will retrieve your trouble codes (using their scanner) for free. I'm not sure, but NAPA and Pep Boys and other such stores may offer the same service....

Eric,

Thanks for the info on Sport Mode. Do you agree that it makes sense to do a flush or fluid/filter replacement first and see if that solves the problem? (I guess that while the pan is off, they could inspect whatever is accessible from underneath.) Could the whole thing be due to a clogged filter?

And FWIW, I'm not 100% sure, but the irregular shifting and slipping seems much more noticeable when I'm accelerating through a fairly sharp low speed left turn (not on right turns). This makes me think that the g force of the turn is causing a momentary fluid starvation in part of the box. This could be due to a low fluid level or clogged filter. Make sense?

Regarding the scan, see my previous message. I had it done yesterday. No faulty transmission codes showed despite the fact that AAMCO told me about two bad ones. Moreover, the only code that showed was P2181, which is a cooling system code that's been there for several months (bad thermostat). AAMCO mysteriously didn't see that code. How do I know that AAMCO even hooked up the scanner ??? (Guess what I'm thinking)

Eric
10-18-2009, 07:44 AM
"Thanks for the info on Sport Mode."

You bet!

"Do you agree that it makes sense to do a flush or fluid/filter replacement first and see if that solves the problem? (I guess that while the pan is off, they could inspect whatever is accessible from underneath.) Could the whole thing be due to a clogged filter?"

Yes. Given the mileage, I'd do a drain/refill & fluid replacement as "normal service." (This ought to have been done, in my opinion, at around 40,000 miles and every 40k thereafter.) I'd also like to have a look inside the pan and yes, a clogged filter could definitely create problems - especially if there's no bypass in the system (I don't know whether your transmission has this feature, offhand). In an automatic, operation is controlled by hydraulic action, through circuits inside the valve body. If passages get clogged or accumulators get sticky, etc., then you get problems with shift quality/feel and so on.

Bottom line: The fluid/filter need to be replaced anyhow. And with the pan exposed, you will know whether there's debris/chunks in there - or not. This will give you peace of mind that (a) the fluid/filter are changed and thus fresh, etc., and (b) the transmission is mechanically ok (no debris/chunks in the pan)...

"And FWIW, I'm not 100% sure, but the irregular shifting and slipping seems much more noticeable when I'm accelerating through a fairly sharp low speed left turn (not on right turns). This makes me think that the g force of the turn is causing a momentary fluid starvation in part of the box. This could be due to a low fluid level or clogged filter. Make sense?"

I have never heard of that happening, but that doesn't mean it couldn't. There's not as much air space in the sump of an automatic transmission as there is in an engine oil pan so it'd be harder to uncover the pump pick-up.I think the transmission would have to be low on fluid to begin with - and then you'd need to subject the vehicle to some pretty extreme lateral forces to get it to the point that it was sucking air... but maybe it's possible.

PS: You have confirmed the fluid level is right... right?

"Regarding the scan, see my previous message. I had it done yesterday. No faulty transmission codes showed despite the fact that AAMCO told me about two bad ones. Moreover, the only code that showed was P2181, which is a cooling system code that's been there for several months (bad thermostat). AAMCO mysteriously didn't see that code. How do I know that AAMCO even hooked up the scanner ??? (Guess what I'm thinking)[/QUOTE]"

Extra cheesy. That shop is either incompetent or crooked. Either way, you do not want to do business with them!

REM
10-31-2009, 12:24 AM
I finally found a trustworthy tran shop in my area. They checked the TCM and found no codes. I had them change the fluid and strainer. They found a little metal in the pan, but just a little. Within the range of normal, they said. No observation of clutch material. They said the fluid level was low. They thoroughly cleaned the pan and put the new fluid and strainer in.

I drove the car out and its perfect. Silky smooth upshifts and downshifts. No stumbling anymore as I roll to a stop. Smoother, quieter operation overall. The car seems a bit quicker too. The car feels like it's two years younger.

Remember when I brought it to AAMCO about a month ago and they insisted that the tranny has to come out for a total rebuild, and they mysteriously found the codes (which no one else found) that supported their diagnosis?

AAMCO = All Automatics Must Come Out

Thank you to everyone here who made me a much smarter consumer.

dom
10-31-2009, 03:26 AM
Happy to hear it!

Very nice.. another satisfied cartomer.

Eric
10-31-2009, 07:30 AM
I finally found a trustworthy tran shop in my area. They checked the TCM and found no codes. I had them change the fluid and strainer. They found a little metal in the pan, but just a little. Within the range of normal, they said. No observation of clutch material. They said the fluid level was low. They thoroughly cleaned the pan and put the new fluid and strainer in.

I drove the car out and its perfect. Silky smooth upshifts and downshifts. No stumbling anymore as I roll to a stop. Smoother, quieter operation overall. The car seems a bit quicker too. The car feels like it's two years younger.

Remember when I brought it to AAMCO about a month ago and they insisted that the tranny has to come out for a total rebuild, and they mysteriously found the codes (which no one else found) that supported their diagnosis?

AAMCO = All Automatics Must Come Out

Thank you to everyone here who made me a much smarter consumer.

This is great news! :D

And also a cautionary tale to others out there who may have a similar problem. Get a second opinion if you have any doubt about what a shop is telling you go with your gut.

REM could have been taken for $2,000 for a repair he did not need.

PS: We hope you'll stick around/tell friends about this site. Your post/thread has been top drawer!

REM
10-31-2009, 08:36 PM
Eric,

I ain't goin' anywhere. :)

<< REM could have been taken for $2,000 for a repair he did not need. >>

Or as much as $5,000.

Eric
11-01-2009, 05:55 AM
Eric,

I ain't goin' anywhere. :)

<< REM could have been taken for $2,000 for a repair he did not need. >>

Or as much as $5,000.

That's good to hear!

I don't want to slam AAMCO across the board (these are franchises and I'm assuming some are better than others). But what they tried in your case was criminal fraud/larceny in my opinion. If they do this sort of thing routinely, they're apt to end up getting a wood shampoo at some point, too...