Jeep Grand Cherokee. Odd gearbox response. Please help.

livi · 03-24-2009, 11:11 AM

Grand Cherokee V8 1996. 120k miles. No major previous issues.

Lately it regularly happens that when I start off, putting her in Drive or Reverse, nothing happens. Its like she is still in Neutral. No movement. If I change the lever around a few times, going back and forth from Drive to Reverse, it will then work again properly.

As far as I know the gear oil was changed as scheduled and the level is OK. What kind of price tag am I looking at here? The car is worth very little on the current market. Actually, particularly with the thirsty V8, its pretty much Stone Cold.

Thanks!

Rot 911 · 03-24-2009, 11:29 AM

I would first double check to see if the transmission fluid is at the right level. From what you describe it could be low.

rattlsnak · rattlsnak's Garage

If the fluid is full.

Common problem. Most of these that do this need a new torque convertor. What happens, is the fluid drains out of it overnight and it takes a minute or so to fill it back up after a cold start. Putting it in reverse first is worse as it requires more line pressure. A walk around to speed up that process is to put it in drive, then L, or Low, then up into reverse, or simply wait a minute or replace it.

jmaxwell · 03-24-2009, 11:35 AM

Low fluid level would be my guess as well. That's the symptoms I've seen before.

livi · 03-24-2009, 11:48 AM

Thanks!

I know how to check the gear oil level on my 911, but I have no idea how to do it on the Jeep. Not even sure where its located..

Regarding the torque converter (or low oil level for that matter), is it a disaster waiting to happen promptly if I keep driving it the next few days?

BlueSideUp · 03-24-2009, 12:00 PM

Markus- I have a '93. I'll take a pic here in a second to show where the dipstick is on the Jeep. Basically start the Jeep up, shift from Park to Reverse to Drive and then back to Neutral. Of course do this on level ground. Pull out the dipstick and check that the level is good.

rick-l · 03-24-2009, 12:18 PM

Quote:

Originally Posted by BlueSideUp

Markus- I have a '93. I'll take a pic here in a second to show where the dipstick is on the Jeep. Basically start the Jeep up, shift from Park to Reverse to Drive and then back to Neutral. Of course do this on level ground. Pull out the dipstick and check that the level is good.

With the engine running

BlueSideUp · 03-24-2009, 12:35 PM

Big red arrow points to the dipstick. Your Jeep is a little newer and uses a slightly different transmission but it should be the same.

My Jeep wasn't running so the dipstick shows way over full.

berettafan · 03-24-2009, 12:38 PM

Whoa there cowboy!

Before you get all dirty 'n such you need to see if that bucket of bolts is throwing any codes!

Check it out and get back to us before high noon!

livi · 03-24-2009, 02:21 PM

Wow! Great help, thanks! Pics and all, terrific!

Bucket of bolts..throwing any codes..? How´s that?

Its almost midnight here and I am working my behind off at the kids ER. I will look into your eminent advices in the morning.

Rick V · 03-24-2009, 02:54 PM

Pat her on the dash and tell her everything will be okay. That should fix the problem.

berettafan · 03-24-2009, 07:17 PM

google something along the lines of 'pulling codes from '96 Grand Cherokee'. In my wifes '01 you turn the key on/off/on/off/on/off/on (give or take) and the odometer will display any error codes in the computer. these can be used to diagnose problems. on my wifes truck every few years the tranny gets all funky and as per the code it 'throws' i replace the tps and all is well.

Lots of DIY help in the Jeep community.

BlueSideUp · 03-26-2009, 10:16 AM

Have you ever adjusted the bands in the transmission? There is a front and a rear band that need to be adjusted periodically and can cause all kinds of shifting problems.

Jeep Forum 44RE Band Adjustment

Here you go...

The TCM, transmission control module, will throw codes just like the Power Control Module will. To read the codes you count the number of times the Over Drive lamp blinks. The Over Drive lamp is located on the over drive switch. Turn the ignition key on & off three times; leaving it in the on position on that third trial.

11 Engine RPM input
12 Output shaft sensor input
13 Vehicle speed input
14 Governor pressure sensor input
15 Throttle position sensor input
16 Transmission fluid temperature input
17 Overdrive override (control) switch input
18 System voltage
19 Internal fault in module
21 Governor pressure solenoid output
22 Overdrive solenoid output
23 Converter clutch solenoid output
24 Overdrive override (control switch) lamp output
25 Internal fault in module
26 Governor pressure sensor offset drift
55 End of code transmission

Zeke · 04-08-2009, 03:54 PM

Just saw this. The Jeeps had internal tranny problems due to processors located within the trans.

lm6y · 04-08-2009, 05:32 PM

Jeep also used a few "bad" seals those years on the accumulator piston. It wouldn't get enough pressure to completely apply the band, and clutches, burning them up over time. The Dodge minivans, Durangos, and quite a few of the front drive cars had the same problem. The symptoms are exactly what you describe.

Or that's what one of my best friends that is the transmission guy at our local Dodge/ Jeep dealer said while we were elbow deep in the trans in my parents Grand Cherokee. He paid for his garage with the warranty time on the clock.

livi · 04-08-2009, 05:48 PM

Thanks for reviving this thread. I checked the oil and it seems to be accurate. Strangely enough it has worked perfectly ever since. Maybe the old lady just needed a little tender attention..

tcar · 04-09-2009, 12:01 PM

Could also be the transmission linkage.

BTW, a mistake a lot (of us) make is to check the fluid in P. Must be in N.

Made that mistake on my 94 Grand once.

BlueSideUp · 04-09-2009, 12:28 PM

An incorrectly adjusted kickdown cable can also cause weird shifting problems on these transmissions.

Zeke · 04-09-2009, 01:20 PM

Quote:

Originally Posted by tcar

Could also be the transmission linkage.

BTW, a mistake a lot (of us) make is to check the fluid in P. Must be in N.

Made that mistake on my 94 Grand once.

What's the difference other than a cog in the drive line?

techweenie · techweenie's Garage

if it's throwing trans codes, you'll get a Check Engine Light.

The OBD1 system can send some wrong signals, unfortunately. I had servos replaced on mine only to find out the codes were being sent because of a bad catalytic converter, and all the code readers and translation tables identified the trans as the issue.

Your symptoms do sound like transmission servo problems. Deal with the symptoms. Do not rely on codes alone.