I'm new to anything grand cherokee but i've ended up with one that has problems shifting. Half the time when taking off the jeep will shift through the gears just fine but not return to first gear requiring me to take off in second. When i put it in park it will start back off in first. The other half of the time it wont shift past 1st gear.
-Now i had it diagnosed at a tranny shop and they said it was the Engine computer and that it runs the transmission too.
-I would just like at least a second opinion from someone who knows these jeeps before I spend $300 on a new computer. Is this a common problem? jeep is at 195k miles

 

has it throw check engine light?

most of the time its the solenoid and governor pressure switch that go bad in these trannys there 100$ each and just drop the pan to replace

the older 94-95 had a TCM located under the dash
the 96-98 trans are controlled by the ECM

 

Not true. The TCM is located under the dash on the drivers side on the 97. It is separate from the PCM but must be "flashed" by the dealer when replaced. If you have the 45RE trans, it's under the hood.

 

I'd replace the governors in the tranny and also do a total fluid change with a new Mopar filter.

The tranny in my 97 Grand was hanging between 1-2 once in a while. I flushed the tranny using a bucket, and changed the tranny filter with a Mopar one. It was a night and day difference.

Also put it in neutral with the ebrake on and check the fluid level to make sure it's up to level. If it needs a quart it will not shift right either.

Tony

 

-93-'95 ZJ's with the AW4 and 42RE transmissions used a separate tcm which was mounted on the passenger compartment side of the firewall, behind the steering column, while the PCM just controlled engine functions.

'93-'95 ZJ's with the V8 and 46RH had the Converter clutch and Overdrive solenoids controlled by the PCM.

'96 - '98 with all engines and 42/44/46RE transmissions ZJs had the transmissions controlled by the PCM

 

I'd do what Tony says before replacing expensive electronics. I had a problem with my 42RE. It -10*F the torque converter clutch and governor pressure set trouble codes. After warmup, everything functioned properly and the trouble codes were cleared and haven't reappeared since I did a trans flush. It seems I had a little water in the fluid and it froze in the solenoids. The dipstick was up about 1/2 inch and snow got into the trans that way. Weird, Huh?

 

Sometimes that's all it takes is a small piece of debris floating around in the fluid to hang it up.