New car added to fleet- 98 JGC/updates

[Hokiefyd]

Caution: a change to ATF+4 may induce even more "slippage" in the transmission at this point. If it already feels loose on Trick Shift, which has frictional properties not unlike Type F, the transmission could be most of the way to the junkyard. They could have been using the Trick Shift as a band-aid just to get it to shift cleanly enough to sell it. Then again, the transmission could be just fine, but the bands or TV cable are way out of adjustment. On the 44RE, at least one of the bands' adjustment mechansim is accessed by removing the transmission pan, so if the 42RE is the same, you'll want to be prepared for that when you do the fluid and filter change.

Does the loose shifting also appear to be occuring too soon in the RPM range, or does it appear to be shifting at the right time...just too soft? A loose TV cable would produce soft AND early shifts. Tightening up the TV cable will firm the shifts, but they'll also come higher in the RPM range, even with light throttle. Very nice that you can "tune" it to exactly how you like it.

 

[Nick R]

Originally Posted By: Hokiefyd
Caution: a change to ATF+4 may induce even more "slippage" in the transmission at this point. If it already feels loose on Trick Shift, which has frictional properties not unlike Type F, the transmission could be most of the way to the junkyard. They could have been using the Trick Shift as a band-aid just to get it to shift cleanly enough to sell it. Then again, the transmission could be just fine, but the bands or TV cable are way out of adjustment. On the 44RE, at least one of the bands' adjustment mechansim is accessed by removing the transmission pan, so if the 42RE is the same, you'll want to be prepared for that when you do the fluid and filter change.

Does the loose shifting also appear to be occuring too soon in the RPM range, or does it appear to be shifting at the right time...just too soft? A loose TV cable would produce soft AND early shifts. Tightening up the TV cable will firm the shifts, but they'll also come higher in the RPM range, even with light throttle. Very nice that you can "tune" it to exactly how you like it.


Slipping shift in this case involves moderate throttle, feels like it shifts at the right time, but the rpms stay the same and it eventually grabs the gear. like a slipping clutch during a shift with a manual. Can last anywhere from 1-3 seconds.

 

[kkreit01]

Looks very nice and clean.

 

[artificialist]

If the transmission needs dramatic repair, using Lucas transmission additive can help you get a few more miles from the transmission.

 

[Falcon_LS]

I've always liked the ZJ. That's a clean example.

 

[Nick R]

It's been about a month, figured I would give an update for those interested. She's put about 1,600 miles or so at least on it, and so far it's been great. The transmission has gotten neither better nor worse (though see end of the post) it still has TC shudder on take off a good portion of the time, and often when cold and occasionally when warm slips the 1st-2nd shift under moderate throttle. No CELs (knock on wood) have yet to replace the amp, so far though it's running great.

In fact, to showcase it's health, here is a 0-60 I took the other evening.


Funnily enough, yesterday morning, the morning after I took this, she was on the way home from school and she thought the tranny died because hit gas and it didn't go nowhere, and there was no fluid in it. Turns out, one of the clips that held the transmission cooler line into the radiator came off and the hose blew off and dumped all the tranny fluid all over the road. Fortunately our mutual friend who is a mechanic and was fortunately not at work was able to fix it and fill it back up to get her back on the road.

 

[MBS500]

loosing all atf doesn't sound good.

 

[Nick R]

Originally Posted By: MBS500
loosing all atf doesn't sound good.



Well it didn't move, the torque converter just spun freely so I'm not *too* concerned about it. I just need to throw another bottle of lubegard in it, unless someone else has a suggestion.

 

[xxch4osxx]

Originally Posted By: Nick R
Originally Posted By: MBS500
loosing all atf doesn't sound good.



Well it didn't move, the torque converter just spun freely so I'm not *too* concerned about it. I just need to throw another bottle of lubegard in it, unless someone else has a suggestion.
I had that very same thing happen on my Silverado, but it was a rubber hose going to an aftermarket tranny oil cooler burst and sprayed all the transmission fluid out. I was driving and all of a sudden the rpm's started increasing like it suddenly went into neutral. Cut the hose and bypassed the cooler and filled it back up with fluid. Never had a problem with the transmission and that was 4 years ago.

 

[gomes512]

Yep same story here, two years ago driving my Grand around with the 42re the cooler line blew off. Felt like neutral alright, thought the pump would be toast for sure but it hasn't shown any signs of trouble thus far. Luckily I cut the ignition as soon as it stopped moving.

 

[dishdude]

Not quite sure why you would do a 0-60 run on an old vehicle with a marginal transmission, but hey it's not my car!

 

[Nick R]

Originally Posted By: dishdude
Not quite sure why you would do a 0-60 run on an old vehicle with a marginal transmission, but hey it's not my car!


Because it's not really any different than how the car is driven normally? Especially when merging onto the highway with our extremely short on ramps.

 

[rslifkin]

I'd drop the trans pan and do a band adjustment on it at some point. That might help out the 1-2 shift a bit.

 

[SwampSurvivor]

Unfortunately, those Grand Cherokees have a horribly unreliable Chrysler auto trans in it.

 

[rslifkin]

Originally Posted By: Miller88
Unfortunately, those Grand Cherokees have a horribly unreliable Chrysler auto trans in it.


They do have a bad rep, but I've seen plenty of them (42REs) last fine (and some die early). My equally hated 46RE is still going fine. Add a big cooler, keep the fluid clean, adjust the bands occasionally, and they hold up well. If you want to add power or do any heavy towing, turn up the line pressure and/or add a shift kit. Most of the issues stem from lack of cooling from the factory and lack of maintenance.

 

[SteveSRT8]

Yep, not only is yours doing fine but so are a ton of others.

And I seem to imagine you are not all that easy on yours!

 

[Kuato]

I've owned 2 GCs with the 4.0, and a trans pan drop + filter and refill every 30k should have it shifting like new after 2 changes.

Make sure to use ONLY ATF+4.

 

[rslifkin]

Originally Posted By: SteveSRT8
Yep, not only is yours doing fine but so are a ton of others.

And I seem to imagine you are not all that easy on yours!


I don't baby mine at all. Plenty of hard driving, some part-throttle shifts with the TC locked occasionally (I've got a manual lockup switch on it), plenty of WOT shifts at 5200+ rpm, and I've towed with it a few times, including towing another Jeep on a trailer with some stuff in my Jeep (about 6500 lbs trailer weight, 11,300 combined, which is just over the max combined rating). When I did that, highway merging was a solid 10 - 15 seconds of sustained WOT. Trans hasn't seemed to care at all.

I'll be swapping trans pans in the spring so I can have a drain plug and add a temp gauge. When I do this, I'll be turning up the line pressure a bit, putting in an upgraded governor pressure solenoid setup (with the upgraded valve body, it floods the gov pressure solenoid at the top of 1st and you have to back off the gas slightly at WOT or it'll just run right into the rev limiter), and also doing a mod to allow TC lockup in any forward gear (currently can't lock in auto/manual 1st, or manual 2nd). Unless it turns out that it's running really cold, I'm also going to replace the trans cooler with one of these, as it's notably bigger than my current cooler (11x11x3/4 vs 8.5x22.75x1.25 inches): http://www.transmissioncoolers.us/4739.html

 

[Hokiefyd]

Dad had a '96 ZJ with the 5.2L and (I guess) a 44RE transmission. We towed a 7,000# travel trailer with it fairly regularly. We also had that thing on numerous Jeep Jamborees and other off-road events (ours had the Up Country suspension). Great Jeep, great mechanicals. Never an issue.

I also had a '97 Dak with the 5.2L and 44RE transmission. Over 170,000 miles on it and it ran just fine. I only sold it because it was a third vehicle and I bought a small trailer to tow that took the place of the pickup bed.

 

[gomes512]

Yeah, the 4X's units weren't that terrible if the fluid wasn't completely ignored. At my local boneyard I see plenty of blown 42re units. The little bit of fluid left in the pans that the yard didn't drain is always either mud or brand new. No maintenance or tried to change to late.

Doesn't sound like a problem for you, but check your throttle valve cable adjustment.