Hi, new here and I have an issue. At work we bought a wj with a blown engine and completely rebuilt a new one for the jeep. Well now we have the engine installed and just got it back on the road and some transmission problems. Once the jeep is up to temp when creeping forward at a stop the jeep shakes and pulses. When you take your foot off the brake to take off it also pulses. Also it takes pretty much all the braking power to hold back the jeep at a stop. We determined the trans was rebuilt sometime before the engine blew.

what we are thinking so far is a dragging TCC. Any thoughts on this?

thanks

 

Welcome to CF!

Sounds like a cracked TC to me.

 

these had a lot of problems with what I refer to as the "conductor plate" in the transmission. it is what connects the solenoids on the valve body. it almost looks like a circuit board. when they are bad they can cause any of the solenoids to act up. I would do this before anything. you have to remove the valve body but its not too hard. at the same time replace the case connector. it has an o-ring that is very common for leaking. if there is any oil in the plug, make sure to clean it with electrical contact cleaner and use a little dialectric grease on reasembly.
Actually, you could probably unplug and check the connector first. at least its free.

 

Took it for spin today and when its dead cold it acts perfect, it will sit still with no brake pedal in gear and comes up on converter stall and takes off.

So far it seems like the stator cant lock up and I cant get any torque multiplication from the torque converter.

 

oops. I was thinking the wrong year. drop the pan and see how much clutch/metal is in it. it does sound like a converter problem but they rarely ever fail on their own. they most commonly fail because of metal contamination from the trans.
The converter should be off which means the boost valve on the valve body is holding fluid at the back of the lockup piston keeping it from applying, or partially applying, (since there is no direct apply pressure at a stop) another common problem is for the boost valve retainer to fail, but again there should not be enough apply pressure to that circuit yet to make the engine shake or stumble, push etc.
so, my guess is going to be valve body related from metal contamination in the transmission.

 

Could the trans mission lines being mixed up at the cooler cause it to shift improperly
I have an o1 grand Cherokee 4.0

 

It shouldn't. It may cause it to be less efficient at cooling, and for maintaining the proper temperature in the transmission in general (even for having the atf fluid being properly warmed up when in colder climates)? From my understanding, a reason for routing these lines how they are is to facilitate priming of the system.

I'm not sure if hooking them up backwards may possibly backflush the cooler? Possibly contaminating the fluid? That could clog the cooler and who knows what else? If debris gets released this way circulating, it may be able to contaminate the other internal components like the solenoid or valve maybe.. This would possibly be able to cause abnormal shifting.