Hey guys.....I'm gettin ready to haul a trailer to florida in my 2001 ram (i think specs are in my sig...) Anyways, here for awhile I've had a problem where when im in OD, around any normal highway cruising speed, the RPMs will slide up by about 1500 then back down to normal into torque lock. It does it very, very frequently. There are a couple things I can do to make it stop or make it happen (sometimes only temporarily).

1. If I let off the gas, wait a second, then hammer on the gas without teh tranny downshifting...it normally holds torque lock for a little while after that.
2. Yes, when I hit the brake while pushing in teh gas, teh RPMS go up while driving down the road.
3. Sometimes it is so rhythmic (unlock, lock, unlock, lock) that I can time it to the exact second it does it....lock 4 seconds, unlock 4 seconds, etc...
5. I replaced my TPS already and it didn't solve the problem.
6. I know theres not a number 4, I was just wanting to keep you guys from being bored.

 

1. Clean the TPS

2. Make sure your brake light switch plunger is adjusted properly, or that it is not worn out. That plunger must be tight up against the brake pedal rod, or the tc will open close, open close, etc.

3. Make sure the trucks vacuum is adequate. If you have insufficient vacuum, the cruise control will disengage, and when it does, the tc will unlock.


The tc will not stay locked up with your foot off the gas. As soon as you take your foot of the accelerator, the tc unlocks. The only way it would stay locked would be if you had an aftermarket controller.


Hope this helps.


Good luck with your ride.

 

not to be an aggravation...but exactly how do i check these things??? LOL

 

You check the vacuum with a gauge or a hand vacuum pump.

And you check the brake light switch by either looking under the dash, or removing the lower panel and observing it that way.

 

sweet, thanks

 

you already replaced tps, and had no change (right), so that rules that out.
best to continue the cheapest things first.
just temporarily, you might unplug the brake light sw, so it cant flutter and see if that helps any.
transmission filter and fluid changed recently ? if not its worth a try.

to continue to collect info,
1. does it unlock/relock on when its on cruise, or also when you are controlling pedal.
2. does it unlock/relock only when going uphill, or all the time.
3. does it only do it in OD, or also when OD is off

if your driving to florida and towing a trailer, try anything to keep it from locking and unlocking repeatedly. that can't be good for anything.

 

I'll try the brake light switch thing....

to answer your questions:
1. It unlocks/locks on both, cruise or no cruise.
2. It does it all the time.
3. Does it in OD or D.

I DID notice something the other day....when I'm running about 85+, it has less tendency to unlock.

 

that's one solution.
you probably need a tc govenor or solenoid or something similar. i see a transmission shop somewhere in your future. desertdog or dieseldemon or somebody recently had this. i think they were able to get it fixed for not too much money.

 

yeah, i'll go to hte dealership and have them look at it..................................NOT!!! lol. im thinkin AAMCO transmission shops or somethin.

thanks for the input, been very helpful

 

I would check/try a few more things before going to the dealer.


1. Change your transmission temperature sensor. Takes 2 seconds, and the part is in expensive. They even come with threadlock on them. Ready to go out of the box. Have you ever towed before with the truck and had the tranny temp warning light come on? It is VERY common for a sensor to go bad to the point where your shifting problems could be from a sensor that is no longer in spec. All from one, good, overheating. On my CTD, when the sensor goes bad, the truck has a hard time going into lockup. Even in warm weather.


2. Make sure ALL your grounds are tight, and free from corrosion. Especially at the battery. A lot of the PCM circuits work on a variable ohm ground. The grounds must be in good shape for the tranny curcuits to work properly.

Pull the tranny wires off at the harnesses, spray them with an electrical contact cleaner, then apply a decent blob of dielectric grease.


If none of this solves your problem, then I would see more qualified help. My opinion is the Rams have shi**y grounds from the factory. I redid my 95' and it runs better than new..LOL.

I personally find the factory trannys to be pretty rugged if used as intended, and the fluid is done properly. I change mine every 15,000. And it NEVER gets over 190 degrees. Even towing on a hot day.

It the trucks electrical system that needed some improvements.


Anyway, this would just be by next level of diagnosis. Just a suggestion is all.


Good luck with your ride.