transmission slip question

[chrisl757]

I have a 1996 4.0L 2wd with 172K. About 2 1/2 years ago, I had a problem with the transmission slipping, or not engaging when I was accelerating from a stop. This caused a good jerk when it did finally engage.

I took it to a few places and was told that I needed a new transmission. Kept asking around, and I ended up having the transmission fluid flushed and changed at a jiffy lube.

That fixed it right away! No more slippage/jerking.

Well, that slippage is back again.

I'm concerned that if I keep flushing the fluid, I am eventually going to push my luck.

Should I just go for another flush, or does anyone have any other ideas?

[fredjacksonsan]

I know a guy that had the same problem as you. Whenever the slip returned, he would drop the pan, changed the filter, and replace the fluid. After doing this a few times, he never had a problem again.

With that many miles, maybe a flush isn't such a good idea, since it may stir up some dirt inside. Just dropping the pan & putting in fresh fluid every 30K miles or so should do the trick.

I'm curious how many miles on it since the last fluid change?

[chrisl757]

It has been 30k miles since the last fluid change/flush. I am concerned that this "flush trick" will only work a few times and then I may bring on some real problems.

When the flush was done at jiffy lube, the seal was not changed! The guy who did the flush told me that it would probably work because if there was any dirt, it would be washed out from the seal. Apparently it worked.

I was told it would be $400 to change the seal. Is this something that I can do myself? I'm pretty mechanical, but have never attempted this before.

Thanks as always for the help!

[wafrederick]

If you want to try something tempory,get a bottle of Lucas and Lucas is the best one on the market.You can get Lucas at any auto parts stores and get the one for transmissions.Lucas does work like it says on the comercial.If you want to do a flush,here is what you do:remove the bottom transmission line and point it to a bucket or pan.Start pouring fluid while the vehicle is running until you see the fluid is clear.This is the better to flush because you can see the condition of the fluid.Make sure you do not run the transmission dry when you do it this way.This flush procedure uses less fluid than the machine.Problem with the machine is it back flushes the dirt and crud from the lines into the valve body resulting in problems later on and uses more fluid.I know a transmission shops that does valve body cleanings and rebuilds because someone had their transmission flushed.

[fredjacksonsan]

A seal may need to be changed if it's leaking. If your transmission is leaking, consider replacing a seal. If it's not, don't worry about it.

wafrederick is right, if you have the mechanical aptitude to change out all of the trans fluid, go for it. If not, dropping the pan and replacing that amount of fluid will work if done at quicker intervals.

There is absolutely NO possibility that fresh fluid will "bring on more problems". Your transmission is designed with fresh fluid in mind. If there's a mechanical problem, there's a mechanical problem, but if changing the fluid fixes the issue, you should be good.

[MagicRat]

Originally Posted by chrisl757

It has been 30k miles since the last fluid change/flush. I am concerned that this "flush trick" will only work a few times and then I may bring on some real problems.

IMO you have nothing to lose by changing the fluid. The only alternative is a full rebuild which is big money. A change is very cheap by comparison. If it can buy you another 30k miles, why not do it?

I should add that auto transmissions do not tolerate slipping well. Often, even just a few minutes of accumulated slippage time is enough to ruin it, so IMO the sooner you flush the trans, the better.

[chrisl757]

Friends,
Thanks for the great info. I have not noticed a transmission leak, and if that means I don't have to replace a seal, so much the better.

I think I could handle the Lucas temporary fix. Where is the bottom transmission line roughly? Is it a hose or line?

Also, how much Lucas should I get if I am going to drain the whole system? Do I replace it all with Lucas, or ATF?

Sorry to ask so many questions, but if this works, it would be wonderful!

Thanks again!

[fredjacksonsan]

Originally Posted by chrisl757

Friends,
Thanks for the great info. I have not noticed a transmission leak, and if that means I don't have to replace a seal, so much the better.

I think I could handle the Lucas temporary fix. Where is the bottom transmission line roughly? Is it a hose or line?

Also, how much Lucas should I get if I am going to drain the whole system? Do I replace it all with Lucas, or ATF?

Sorry to ask so many questions, but if this works, it would be wonderful!

Thanks again!

The Lucas product is a good one, directions are on the bottle. You'll want to replace the fluid with ATF, and add the correct amount of Lucas to it if you decide to go that route.

[chrisl757]

All,
I wanted to post the results of my work on the transmission. I spent all day getting this done. 9 hours total to pull the pan, change the filter, reinstall the pan and then flush the system with new fluid.

Here's my summary of experience for posterity and anybody else who dares to do this:

I got the pan unbolted pretty easily. Of course there wasn't any gasket. Just some RTV that took quite a while to get off. Note to novices: buy RTV gasket remover if there is such a product. Brakeclean didn't do much to get the gunk off.

However, the pan did not just come out. because of the exhaust and the crossover bar, it had to be worked on. If the dipstick tube had separated (as it should have at the midpoint), this would have been much easier, but it didn't. The tube attaches to the engine from a 1 inch piece of metal. I had to pull the pan out with the entire tube attached. Not fun if you don't have your jeep on a lift.

By the way, I had to pull the filter out BEFORE I could get the pan out. On the reinstall, I first guided the pan in from the bottom (carefully guiding the dipstick tube through the engine cavity). Once the pan was "in place," I lowered it a little so that I could put the new filter in. (I couldn't fit the pan in with a new filter in place--too hard to get pan in place.)

I will say that I understood why the last guy didn't put the gasket in, because it took over an hour to get the pan in place to the point where I was ready to start putting the 19 bolts in. In that time, the gasket started to fall down, and I had to readjust for the next hour to get it back in place! I didn't use enough RTV to really get the gasket to stick in place I guess.

Now, after that was done, I flushed. I pulled the return line that goes into the radiator (that is the top one for anyone who wants to know) and dumped it into a bucket. Make sure your bucket has some marks on it to measure volume, because it made it easier to let me know how much new fluid to put in. I started up the engine and started putting new fluid in the dipstick tube and waited until I had clear red fluid coming out. It took about 13 quarts to get to that point, and at first it looked like motor oil coming out.

And now the test drive: No More Slippage. Transmission runs as good as new. And it only cost $50 with fluid, gasket, filter, and drain pan. But that dipstick tube made it a lot tougher.

Thanks to everyone for the help. It worked, and hopefully, I can squeeze another 30K out the transmission before I have to do this again.

[Scrapper]

i'd still change tranny fluid and filter about 3 times..as i've had a few problems with people coming saying need new tranny about 8 out of 10 it cured it and you might wana take a magnet to the fluid you take out see if theres a bunch of metal shavings in fluid,,,good luck

[fredjacksonsan]

Sweet....fresh fluid can work wonders.

Now if you "just" drop the pan every 30K, it should be good to go.

[AlohaBra]

Hey Chris...was that filter dirty?? Just curious...

[chrisl757]

I couldn't tell that the filter was dirty. It looked pretty good compared to the new one. At least the fine wire mesh screen that is visible was not clogged. The magnets did have metal filings to be sure, but I think for a tranny at this age with 30K since last fluid change, there is going to be some filings in there.

[thinmints]

Originally Posted by chrisl757

I couldn't tell that the filter was dirty. It looked pretty good compared to the new one. At least the fine wire mesh screen that is visible was not clogged. The magnets did have metal filings to be sure, but I think for a tranny at this age with 30K since last fluid change, there is going to be some filings in there.

AHH the dreaded tranny pan removal i attempted that ONCE!! Whoever thought that having the tube seperate at midpointe should have there Nuts in a vice, After hours of getting nowhere i decided to just take it to the Local Jeep Dealer and pay the $129.00 to have them replace filter and pan gasket It took them about 6 hrs but they got it done, i was laughing the whole time because i saw several of them fighting the same tube that i was dealing with Something's are just worth paying extra foropcorn: