TonyB

This has happened twice so far. It's only when i'm out on the trail and really REALLY romping on it in 4LO.

What happens is the transmission seems to go into "limp mode". Meaning, it's like stuck in Drive. When you mash the gas, it'll hardly accelerate(like you're taking off in way too high of a gear). Putting it in 1st/2nd/3rd has no change in acceleration. Reverse seems to be OK though...not sure why on that one.

The "fix" is to disconnect both battery cables from the battery and touch/connect them together for a few seconds then hook them back up to the battery.

It's like the transmission has a brain fart and says, "STOP HURTING ME!!!".

Is this a heat issue? An RPM issue?

Any help/experience is appreciated.

ken72

Sounds like a computer issue. May need to have it reprogrammed or install a new one.

TonyB

Just for reference, what year Cherokee computers can I use in my automatic 94? I've often thought of carrying a spare, as i've seen one take a crap out on the trail before.

G_P

I think any auto tranny computer from 91-96 should fit. Not sure about the older or newer ones.

You might consider installing an auxillary transmission cooler as well. I put one in and it has made a big difference especially on hot days in low gear.

TonyB

Thanks. Did you just cut a metal line from the trans to the radiator and "splice in" the cooler?

1991Jeep_Man

Not that complicated. Go to advance, and get a medium or heavy duty tranny cooler, and then some hose clamps. Connect one end of the hose to the return part of the radiator cooler, then connect the other end to the actually tranny line. All hose clamps. I think it's all included in the kit.

TonyB

Thanks, just got done googling some write ups. Some people just bypass the whole radiator.

1991Jeep_Man

No! Don't bypass the radiator tranny cooler. BAD IDEA. At idle, when fan speed is low, your radiator tranny cooler does ALL the cooling. If you are at low RPM and not moving fast, then your tranny will cook faster than you can say "Dammit" lol.

TonyB

10-4, sounds like a plan. Thanks! THE INTERNET SAVES ME YET AGAIN!!!

1991Jeep_Man

Good luck with it. O, and btw, if you SERIOUS off-roading or hauling in hot weather, some guys actually mount a small fan and temp gauge with their coolers. Allows you to keep and eye on tranny temps and give some extra cooling if needed. Just thought you might wanna know. I think they use little 7-10 in fans.

TonyB

Yea, i've seen that too. I'll just see what space and budget looks like at the time of doing this.

Rock Toy

Tony some guys save money by going to the JY and picking up a Suburban trans cooler, cleaning it up real good and using it. 10-15 bucks.

TonyB

Yea, i've been browsing/reading about that. I'm jotting some things down to look for when I goto the Pull A Part next outting.

Rock Toy

Luck!

TonyB

They're outta that!!