Just a quick post here. I’ve recently had some transmission problems. It sounds like a whining/whirring noise when revved and when In idle. The jeep has 0 power after a few minutes of driving and will not shift. The torque converter doesn’t lock up. After 5 min of driving it won’t move at all and I basically have 5 neutrals. I can pretty much guarantee that it is the tc but I just wanted a second opinion. I’m very experienced with xjs and know them in and out. But before I drop the trans does anyone know how I can know for sure it is the tc and not the actual transmission oil pump?

 

Yes, there is a "stall test" outlined in the FSM that diagnoses a failed TC.

Basically chock and foot brake it, rev it hard for 5 secs in drive, and record the max (or min) RPM.

It should be between 2100-2400 RPM, under or over and you have a cactus TC, repeat in reverse (as per FSM for AW4)

If you have a bad oil pump, I would expect a whining noise and glitter in your trans oil

 

ah yes I remember now. I will do this tomorrow and see what happens. I suspect the tc is shot. Any suggestions for a good TC that is not too expensive?thanks.

 

a used one from the wreckers would not be much

they can also be rebuilt by a good transmission shop for under $300

I imagine a new one can be obtained in USA, (google it)

I advise to change out the front seal, its costs $20...guess how I found that out

 

Another quick question. Would the torque converter being bad affect wether or not it will move when not in OD(4th gear). For example it hardly will move when I pull away from a stop, you basically have to redline it to go anywhere. I am asking this because I am wondering if it might be a clutch pack or something inside the tranny that is bad.

 

I presume you have tried to disconnect the TCM and see what happens if you operate the stick manually ?

You also should check the solenoid resistances from the TCM connector, or the solenoid connector at the side of the engine near dipstick

It could be a clutch pack, but you would probably expect either reverse, or at least some gear to work

 

Ok so the stall speed test only passes when it is in the first couple minutes of running. After that is stops working and fails the stall speed test. Still possibly the torque converter. Maybe it stops pumping after a few min of being on?

 

Lot's of times trans behaving different cold vs. hot has to do with an internal seal that is done. Hot fluid goes through a leak a lot more than cold does. OTOH, a cold seal may be stiff and block flow and a hot seal softer and lets fluid blow by. Depends on the type of seal failure and the size of the leak which behavior dominates. This could be internal to trans or internal to converter.

My next step would be to use the factory service manual test procedure to check hydraulic pressure at the various test ports. This can usually tell you if it is the pump or an internal leak, and which internal part has the leak.

 

The problem is wasnt so much with the temperature because in one or two min the tranny fluid temp hardly changes. After a min of it being on it just won’t move in any gear regardless of the pcm being unplugged or not. You have to rev it very high to get it to go anywhere. And on top of that there is a pretty loud whining whirring grinding sort of noise sound coming from the bell housing. It fails the stall speed test within 30 seconds to a min of run time. So I want ahead and pulled the tranny and tc today. Is there a way a transmission shop can test if a tc is good or not? Or should I just buy a new one and install it.

 

Well I certainly am no expert but with the transmission issues I am having on my '95, I will be replacing my torque converter if I get that far in teardown. But I would still have mine tested if that is possible and not too expensive.
Mileage? Depending on how high the mileage is, I would think a reman from local parts store would be more reliable than keeping the existing. Looks like they're in the $150.00 range. Maybe cheaper in the long run? Just my 1.5 cents.

 

Yeah we are on the same page in that way. But the whole reason I pulled the transmission is because I am having problems with the tc or the tranny but haven’t decided which one it is. I am only asking all these questions because I don’t want to install a new torque converter on a fried tranny if that is the case. I’m pretty positive that it is the TC. I guess I will just have to take a risk and install it and see if the problem of the no-go jeep is fixed.