macgyver35

My trusty battle wagon gave me a birthday present by having the trans take a dive this morning in the way to work. It seemed like it's been feeling a little funny for the last couple of weeks, but I couldn't quite put my finger on it. Now, I have no 2nd gear, and the converter doesn't seem to be locking up. I start out fine, then it shifts and I bog down, and it take me forever to get up to speed.

If I'm going to have to pull the trans, I'd rather have a rebuilt going in, rather than a used. This is my DD and only vehicle, so I need it to be reliable. I put an ATK longblock in it 4 years ago, and it is in otherwise great shape for it's age. But the trans has about 220K miles on it now.

Any advice on a source for a rebuilt? I'm in the Dallas/Arlington/Fort Worth area if it matters.

I also realize that this MAY just be a case of bad solenoids. I'm going to check resistance on those when I get home tonight, but I wanted to start exploring options.

Thanks

CCKen

Does your CHECK ENGINE light work? Stored or pending codes?


How long has it been since you checked the trans oil level, and sniff checked it?


What trans fluid are you using?


You can check the transmission output speed sensor, and other TCM inputs from the TCM connector using a digital multimeter,


TheTransmission Control Module (TCM) uses the Output Speed Sensor (OSS) todetermine shift points and TCC engagement points.


Read through these connector pin outs and instructions carefully.


Use safety pins to probe the TCM connector pin cavities.

macgyver35

Thanks for the detailed response! I'll be able to troubleshoot when I get home. CEL did come on, but of course I don't keep my OBDII scanner in the Jeep with me. When I get home I'll pull codes.

Fluid shows to be in normal range, and I did a full flush on it about 3.5 years ago. Fluid looks clean. In fact, I did a write-up on how to a full "forward flush" using the transmissions own pump, and it has been quoted and used by several forum members since.

It may turn out to be minor. Maybe I just need a solenoid kit, or something similar. But with the fact that my wife's car was t-boned last week and will be going in the shop next week for repairs, right as we are supposed to go on vacation, I'm trying to line up sources for all possibilities so I can get it fixed and working before our vacation.

cruiser54

Check out this thread:

https://www.cherokeeforum.com/f2/aw4...1/#post3153230

macgyver35

Okay... Got home to check things out.

First, When I left work it shifted normally. It had all day to cool down. But within 7 miles of highway traveling, it went back to skipping 2nd gear.

I got home and hooked up my code scanner.
P0700 and P0753

Results of TCM testing (keep in mind on the readings it was a 90 degree day today, and I did this within 30 minutes of getting home, so things were still hot):

Section 2 - Test 1 = 756
Section 2 - Test 2 = 756
Section 2 - Test 4 = 911
Section 2 - Test 5 = 25
Section 2 - Test 6 = 0
Section 2 - Test 7 = 25

I also did Cruiser's suggestion with the two large connectors. Then I crawled under and looked at what I could of the harness, and didn't see anything, but being a 4x4 there a big linkage bracket in my way of being able to see one of the looms very well.

And that's as far as I got before it got dark and the mosquitoes started eating me alive.

It looks like I have a problem with Solenoid A, or the wiring that goes to it. Given that I'm skipping 2nd gear, does that sound correct? With it being Wednesday, I think I'm going to jump on Amazon tonight and order a set of solenoids so they'll be here by the weekend. If I get into it and find the harness is damaged I can always return the solenoids. I'd like to be able to find a new harness before the weekend in the Dallas area as well.

jpmarine6786

Mine did that exact same thing yours is doing. I was driving one day in that hot summer sun through a neighborhood and stopped at a stop sign. Went to take off and when it went to shift into second gear it didn't do it. CEL came on with 0753 and 0700. Replaced the solenoids and it worked good. That was over 3000 miles ago. Mine would shift fine while cold or moving but if you got stuck in traffic it stopped working. Currently has 203k on it.

CCKen

Those sure are some odd readings - all out of spec. Are you using an auto ranging digital Ohmmeter? Not good. Test 4 should be 60 Ohms.

That aside, "0" Ohms for Sol A does look like the bad guy (1-2/3-4 Solenoid).

CCKen

Before replacing the solenoids, drop the pan and check the resistance of Solenoid 'A' while it is still installed (see pics below).

If the resistance is between 11 and 15 Ohms, the wire from the solenoid to the TCM may be bad. You can check it but let's cross that bridge when you get to it.




.




.

macgyver35

I went ahead and ordered a solenoid kit from Amazon so it would get here by Friday in case I needed it. I was trying to find a solenoid harness as well. Figured if I was going to be in there I might as well replace it. Wow! Are they proud of those things! Around $240! At any rate, nobody nearby had one, and if I ordered it online it wouldn't be here by the weekend.

I tried calling Transtar in Irving, but the person I spoke to couldn't find a listing for a "shift solenoid harness", and could only pull up a (Female external 6 pin connector" for $16.56, but she had no picture. Doesn't sound like my part. I did find the factory part # of 04897742AB, but so far I haven't been able to cross-reference that to nay aftermarket parts online.

Thanks again for all the assistance. I truly appreciate it.

macgyver35

Well, a few hours in the garage to replace the shift and lock-up solenoids and she's back in business! Unfortunately, the harness electrical connectors were so brittle from age and heat that the locking tabs broke off of two of them. I had to get creative with some zip-ties in the hope that they would keep them from coming unplugged.

By the way, I bought the three-piece set of solenoids for $160 on Amazon. O'Reilly wanted $224 PER SOLENOID!

Thanks for all the assistance.

t.mcginley.jr

Stuff like this make me think about getting an aftermarket trans cooler for mine, but then again if they lasted ~200k+ miles then who cares?