Trans or Torque Converter Slip?
 

I was doing some light wheeling yesterday and had something kind of weird happen. I had been driving on mostly dirt roads with my wife and kids so nothing major. Anyways I was climbing a kinda rocky hill in 2wd when the front got hung up I tried to just power over it, the engine revved but it felt like the trans was slipping usually in this situation the rear tires would break loose instead the revs just climbed. I went ahead an put it in 4 low and climbed it no problem. The rest of the day was fine no slipping but it was never really tested, I'm wondering if this is something I should worry about or not and if it would have been the Trans or Torque Converter slipping.

Sounds like the rear tires had really good traction and the torque converter was slipping to me. How high did the revs get before you shifted into 4 low.

I would say around 2000 rpm's. The weird thing is I tried to do a stall test today and it would spin the tires when I was trying to power brake it, but everything was cool and yesterday it was running a little hot.

Time to check the color of your trans fluid. What does it look like?

I dropped the pan and changed out the filter a couple thousand miles ago but when I did the fluid was really black, like used oil black.

Okay, I thought so.

I had the same problem a couple of years ago. When hot, it would slip badly, as in, "I'm not sure I'm going to make it home!" badly. When cold, it was fine. My fluid looked like that.

Some folks will tell you to do trans service like you did (don't bother dropping the pan, just drain it) a few times, running it 15-20 minutes each time, until the fluid is clean.

Yeah, you can do that, and it's good. But, I think there's a better way. Here's what I did:

Parts required: A couple of feet of rubber hose that will fit the metal trans lines; I think it's 5/16".

A few hose clamps to fit.

A good funnel for putting in trans fluid. You want a BIG one.

A drain pan.

You also need at least one helper, and it's easier with two.

Locate the trans line that comes OUT of the transmission. That's the FORWARD line coming out of the trans. Rear = RETURN. You want the front one coming FROM the transmission. Front = FROM.

Cut that line just behind the radiator. Why there? It's easy to get to. That's all.

Run a rubber hose from there to a drain pan. No need to clamp it.

Get your funnel in place in the dipstick tube, and get a couple of gallons of new DexIII/Merc trans fluid ready.

Have Helper #1 watch the hose that's coming out of the trans into the drain pan. Helper # 2 will start & stop the engine on command. You will pour in the new trans fluid.

Have the engine started, and start pouring in trans fluid. You want to pour it in at about the same rate it's pumping out into the drain pan. Helper #1 will tell you when the fluid coming out is CLEAN.

You will probably run out of fluid in the gallon jug before things are clean. When you run out, STOP the engine, get the new fresh gallon ready, and start again.

Once the fluid starts coming out clean, you have flushed out ALL of the old, tired crud and you have a nice, clean transmission.

Finish up, cut a 3" piece of rubber hose and use it to splice the trans line you cut, clamp that in place, check your fluid level like you normally do, drain or add as needed, and you're done.

I have about 40,000 miles on my transmission since doing that. I do some heavy towing (more than I should at some points), and I have not had ONE BIT of slipping since then.

If this doesn't fix it, you probably have more serious issues, but this is pretty cheap and easy and may be all you need.

I'd use some store brand trans fluid for this. No need to go expensive. If it works, great, put another 10,000 miles on it and do it again with some better quality fluid. If not, well, you didn't waste expensive name-brand trans fluid.

:cheers:

Awesome thanks! I will try this today and let you know how it goes.

So I did flush my transmission yesterday with help from my brother and I was actually shocked by the difference it made. Right away it shifted quicker and firmer. I did drive around town enough to make sure everything warmed up and it still felt great. Now fast forward to this morning and my drive to work when everything was cold. It felt like it had a shift kit installed, it shifted kind of hard until things warmed up. Not whip lash hard but you definitely felt the shifts. Is this indication of another problem? Or is should I just drive it and not worry about it? I'm kind of paranoid about Transmissions because I had a 4L60E go out in my 96 Chevy that a local tranny guy rebuilt 4 times over 6 months after the last time said he wouldn't uphold the warranty anymore. I sold the Chevy for a 05 Ram 3500 that I destroyed the torque converter in and had to replace with a billet one.

Check the motor and trans mount. Every time I have a dead mount it shifts pretty hard. Could be many other things though.

Feels like a shift kit hey..lol your trans throttle valve cable might be a little tight and need adjusting. If its to loose it will take forever to shift. If to tight it feels really sharp like a shift kit. Check out the this vid on how to adjust it and see if that helps..

Thanks for the tips I did adjust the the Throttle Valve Cable a few weeks ago but I'll try again and see if I didn't get it adjusted correctly and I'm thinking that I do need new motor mounts. My dad gave me the Jeep this spring and I started building it up. He had it for 15 years and didn't do a thing to it so I know it's still on the stock motor mounts.

If you do motor mounts do the trans mount at the same time.

Heh.

Chalk up another win for a transmission flush done the right way! :cheers:

I'm going to bring up this old thread to ask a few questions.

I took my 2001 XJ to a shop today to get a few U-joints put in (on the road, limited tools, peace of mind, yada yada...). While it was there, I went ahead and had him read a CEL code that had just recently came up: he informed me that it's throwing a code for a slipping torque converter. He checked my tranny fluid, and not to my surprise it was fairly burnt (I've been towing heavily).

He told me that he would recommend driving my Jeep until the Tranny is ruined because flushing the fluid would likely make things worse by removing some of the gunk holding my transmission together. Obviously, that doesn't sound like a great plan to me...

After reading this post, I kind of think a flush would be a good idea, but is it possible that I should just let it ride?

(Background info: 154K miles, Auto trans, have had limited slip issues to date, sometimes feels pretty rough shifting into Reverse)

Naa dont let it ride,I would give it a few good drain and refills, 2 maybe 3..with Dexron III/Mercon.. and see if it helps.. The AW4 is a tough little cookie.
Drain out old fluid,, fill with new, drive for 10 mins, drain and do it again until it looks good.
No need to power flush.