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eesquared
09-28-2011, 01:00 PM
What is the problem when a car lurches instead of automatically shifting? I am talking about the '86 El Camino. When I am trying to keep a constant 35 mph, it sometimes 'lurches' instead of shifting to a higher or lower gear. It's almost like it gets stuck at 35 mph.

I try not to keep it 35 for that reason, but sometimes I have to slow down to the speed limit. My car just does not like to go 35 - it acts funny at that speed.

Any guesses?

dom
09-28-2011, 06:08 PM
Check the transmission fluid and kick down rod linkage.

If you have not done a tranny filter and flush now might be a good time.

dom
09-28-2011, 08:12 PM
I am not sure, but the term you might be looking for is "hunting for a gear?"

grouch
09-28-2011, 09:22 PM
What is the problem when a car lurches instead of automatically shifting? I am talking about the '86 El Camino. When I am trying to keep a constant 35 mph, it sometimes 'lurches' instead of shifting to a higher or lower gear. It's almost like it gets stuck at 35 mph.

I try not to keep it 35 for that reason, but sometimes I have to slow down to the speed limit. My car just does not like to go 35 - it acts funny at that speed.

Any guesses?



What transmission do you have? If you have a three speed, like a turbo 350 or 400, it may need a little bit of service. If you have a 4 speed automatic, your lock up torque converter may be shuddering and having trouble engaging.

If you have the regular automatic, I'd see about a fluid change and maybe adjust the kickdown linkage like Dom said. Your car is one that can have one of several transmissions depending on how it was built so I'm just guessing.

dom
09-29-2011, 12:25 AM
Hopefully you have a turbo 350, or a 400. Those are good transmissions.

I know a sure fire way to make that unit slam into second gear if it's a 350 (only takes a few minutes too). Don't think you wanna do it though.

Pull the dip stick with the unit at running temperature and check the tranny fluid with it in park. Check the level, then rub it on a white paper towel take a picture and let us see. -if you want

note: make sure you pull the stick out first, wipe it, then re-insert to get an accurate reading. Do it a few times to be sure.

eesquared
09-29-2011, 08:12 AM
Check the transmission fluid and kick down rod linkage.

If you have not done a tranny filter and flush now might be a good time.
Oh - ok. Maybe I do need to change the fluid. I'll get Hubby to check the linkage - I do not know how to do that. Thank you~

eesquared
09-29-2011, 08:15 AM
What transmission do you have? If you have a three speed, like a turbo 350 or 400, it may need a little bit of service. If you have a 4 speed automatic, your lock up torque converter may be shuddering and having trouble engaging.

If you have the regular automatic, I'd see about a fluid change and maybe adjust the kickdown linkage like Dom said. Your car is one that can have one of several transmissions depending on how it was built so I'm just guessing.
I have the 700 r..something transmission. I have the 4 speed/overdrive automatic. I'll get hubby to check the torque converter. Thank you~

eesquared
09-29-2011, 08:17 AM
Hopefully you have a turbo 350, or a 400. Those are good transmissions.

I know a sure fire way to make that unit slam into second gear if it's a 350 (only takes a few minutes too). Don't think you wanna do it though.

Pull the dip stick with the unit at running temperature and check the tranny fluid with it in park. Check the level, then rub it on a white paper towel take a picture and let us see. -if you want

note: make sure you pull the stick out first, wipe it, then re-insert to get an accurate reading. Do it a few times to be sure.
No, it's not the 350. I'll check the fluid to see what it looks like.

grouch
09-29-2011, 09:30 PM
I have the 700 r..something transmission. I have the 4 speed/overdrive automatic. I'll get hubby to check the torque converter. Thank you~



That would be the 700R4. It's a good unit. Basically a turbo 350 with an overdrive unit. If the kickdown linkage is a little bit too short, it won't put you into passing gear and it will hunt for a gear.

GM had a lot of trouble with their lockup units in the late 80's. If you ever pull up to a light and it acts like a manual shift car when you forget to push in the clutch, the lockup isn't unlocking.

To be honest, I would have a good transmission shop look at it. You can burn up a good unit if you're not careful. Don't go to a national chain for work, go to a local shop that actually rebuilds the unit. Places like Aamco swap out transmissions to churn them quick. I had one they said was shot but it didn't feel like it wa shot. I went to a local shop I remembered from my racing days and he replaced a sensor. $80 against a $1800 replacement.

dom
09-29-2011, 10:01 PM
700 R4 is a sweet tranny. You have a good car!

eesquared
10-04-2011, 09:27 AM
That would be the 700R4. It's a good unit. Basically a turbo 350 with an overdrive unit. If the kickdown linkage is a little bit too short, it won't put you into passing gear and it will hunt for a gear.

GM had a lot of trouble with their lockup units in the late 80's. If you ever pull up to a light and it acts like a manual shift car when you forget to push in the clutch, the lockup isn't unlocking.

To be honest, I would have a good transmission shop look at it. You can burn up a good unit if you're not careful. Don't go to a national chain for work, go to a local shop that actually rebuilds the unit. Places like Aamco swap out transmissions to churn them quick. I had one they said was shot but it didn't feel like it wa shot. I went to a local shop I remembered from my racing days and he replaced a sensor. $80 against a $1800 replacement.
No, it doesn't do that when I stop at a light. It acts normal then. I suspect the linkage just needs adjusting.

I checked the fluid hot, and cold. It is clear both times.

eesquared
10-04-2011, 09:29 AM
700 R4 is a sweet tranny. You have a good car!
That's what Hubby said about the transmission. He said they still use that transmission in cars that they build today.

eesquared
10-04-2011, 09:35 AM
I just returned from a long road trip from Houston to Mississippi and back. The transmission did not give me any trouble at all. There were not many opportunities to keep it at 35 mph, but it performed very well at 85+ (I do not know the exact speed because my speedometer only goes to 85...), and in cruise mode.

MikeHalloran
10-04-2011, 11:59 PM
Have a good _local_ shop check it, _before_ it breaks something expensive.

grouch
10-05-2011, 08:58 PM
I just returned from a long road trip from Houston to Mississippi and back. The transmission did not give me any trouble at all. There were not many opportunities to keep it at 35 mph, but it performed very well at 85+ (I do not know the exact speed because my speedometer only goes to 85...), and in cruise mode.



I have a Tom Tom and a hand held GPS unit. Both will function as a speedometer. My Mercedes reads only to 85 but it will do 120+. I've done it. The Tom Tom will even alert you if you're speeding.

eesquared
10-06-2011, 07:42 AM
Have a good _local_ shop check it, _before_ it breaks something expensive.
Ok - thanks Mike. Now I have to find good_local_shop.

eesquared
10-06-2011, 07:46 AM
I have a Tom Tom and a hand held GPS unit. Both will function as a speedometer. My Mercedes reads only to 85 but it will do 120+. I've done it. The Tom Tom will even alert you if you're speeding.
I am in the process of ordering new gauges, including a new speedometer. I do not want a GPS. I do not need a GPS to tell me that I am speeding - I already know that.

Besides, I have an aversion to GPS. It negates the function of learning to read a map.

grouch
10-06-2011, 08:16 PM
I am in the process of ordering new gauges, including a new speedometer. I do not want a GPS. I do not need a GPS to tell me that I am speeding - I already know that.

Besides, I have an aversion to GPS. It negates the function of learning to read a map.



The Tom Tom was a gift from an ex-girlfriend. The GPS was my speedometer on my tube frame dune buggy. I still use it as it shows actual time and distance traveled. A friend left in on in his luggage once and he kept the highest speed reading. He was pulled over once and the police officer wanted to look at it to see what his top speed was. When the top speed of 480 mph came up, the cop gave it back and told him to go on his way. After all, how could the officer prove he was actually going that fast on the road? That's what dedicated racers do on the salt flats. I'm hoping to get my 200 mph hat in the next couple of years.

eesquared
10-14-2011, 09:16 AM
The Tom Tom was a gift from an ex-girlfriend. The GPS was my speedometer on my tube frame dune buggy. I still use it as it shows actual time and distance traveled. A friend left in on in his luggage once and he kept the highest speed reading. He was pulled over once and the police officer wanted to look at it to see what his top speed was. When the top speed of 480 mph came up, the cop gave it back and told him to go on his way. After all, how could the officer prove he was actually going that fast on the road? That's what dedicated racers do on the salt flats. I'm hoping to get my 200 mph hat in the next couple of years.
Well, be sure and let me know when you top that speed, and I'll raise a toast to you.

grouch
10-19-2011, 08:48 PM
Well, be sure and let me know when you top that speed, and I'll raise a toast to you.



Myself and a couple of buddies are getting ready to build a car for next year. We're down to a Camaro, a chopped and channelled street rod (I'm not sure exactly what it is yet) and a 2000 Mustang that was a flood car. I'm not a big fan of Mustangs but it will be the easiest to build since we have to pull all the mechanics out anyway and there are plenty of custom parts available.

I'll be happy with a 200 mph hat but the ultimate goal is 225.