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Transmission doing crazy things!

A

AKswampheep

NAXJA Forum User
Location
INDIANER
Ok i have searched for similar things, but cant find it.

Main problem has been when driving for a while in OD, if you make it shift into 3rd it will slip, bad, but you put it in 3rd manually, it will lock the TC and drive fine. also while in OD, after driving for a while, you sit at a stoplight, and it will be stuck in 2nd or 3rd gear, will barely move.

This could be an answer to the main problem, my check engine light is on, saying that the transmission is out of range, i belive its code P7040 or something very close to that. If you put it in 1-2, it will start in 1st and shift into 2nd at normal rpms, then in 2nd once it hits a certain rpm it tries to shift back into 1st... WTF!!!!

Somebody please help me. : /
 
What year, milage?

When a Throttle Position Sensor goes south it can do some really funky things to the shift points on a tranny, especially when everything is electronically controled, as is the case with the AW4.

But, the fact you're getting a code for the tranny being out of range is making me think that one it's (the tranny's) sensors is bad. Did it throw any more codes?
 
Ok well this is getting very bad. To the point of, the TC is slipping so bad that i can hardly get up to speed on the highway, but only when driven for a while. If i start it up when cold or just has been sitting for a while, it is fine.

I havent tried replacing anything yet, as i dont have the funds at all to be going at this randomly. What could be doing this?! Do i need a new transmission?! I even changed my tires from 35's to the stockers to relieve the transmission some, and its still doing this!

Please help!
 
you checked the fluid right? im not trying to be an ass - low atf will make the trans slip like that as well.
 
There is also, sometimes when it gets bad, a hissing, scraping kind of sound, coming from somewhere in the transmission, does it in park, and all the gears, Im just totally confused, as these people sware on here that you cannot budge a AW-4, hope to god its something electrical.
 
I hate to say it but it sounds like the seal in the pump section is crapping out. This causes the pressure to drop when the fluid gets hot. Try a can of TransMedic. It has some lacquer thinner in it that softens and swells the seals. Personally I just dumped a cup of lacquer thinner in mine since I had it on the shelf.

The only way to tell for sure that is what is happening is to measure the pump pressure with a gauge. I picked mine up for around $40.
 
OK well, i just went out and tried some things, and unplugged the battery, and unplugged the TPS, made sure the contacts and as much as i could see was clean, plugged it back in, hooked battery back up. I went for a test drive, and it was fine for about a good 5 minutes of hard driving, now not upshifting to 3rd and slipping like crazy, it was doing what it should..

Now the bad, i was going back home down the highway, and a large tractor was going about 5mph, i could hear the slipping scraping noise start to happen. I shut the jeep off for about 5 seconds, started it back up rolling, and the noise went away.. curious, i went down the highway about 70, with the TC slipping. Shut the jeep off, started it back up, put it in OD, and it willingly grabbed in OD for about 5 seconds, then started slipping again. The noise also again went away. WTF is this, its driving me nuts.
 
It sounds like the problem's down in the guts of the trans. Scraping noises mean thrust bearing or bushing failure, bad one-way, planetary issues or a few other things. Pull the pan and check for metal. If you find any it's done.

Kinda seems like the AW4's bombproof image is fading away lately. I wonder if we're reaching the fatigue limit of the factory seals causing all these failures.
 
I sort of stray away from believing its done for.

It seems like it has to be something electrical, because if the scraping noise starts, i shut the jeep off, and start it back up, it disappears.

I just drove all the way to my moms (drove very... very hard to try and make it happen again) which is about 15 miles, NO PROBLEMS. Drove back,(very hard once again) 0 problems. Seems like something might have just... got caught up in it? i dont know.

Its driving completely PERFECT now. Odd stuff.
 
AKswampheep said:
does this sound like something the TCU could be doing?
Click to expand...

Well, diagnostic step 1 in the FSM is to disconnect or pull the fuse for the TCU and verify that it shifts manually using the shifter. Also, since you mentioned scarpping noises in the bellhousing area, you might want to pull the inspection cover and check that the torque converter bolts are all tight and there are no cranks in the flexplate.
 
Does anyone have a picture of where the TCU fuse is? OR is it in the fusebox underneath the hood, and what would it be labeled as?

Also i looked for a inspection conver on the tranny? Didnt see one. I just peeked under there as i was adding my last leaf onto my rustys springs to get the rear outta the tires.
 
What year are we talking about? The Renix engines have a fuse in the harness right up near the TCU, which is located under the lower passenger side of the dash. HO engines I think have the fuse in the PDC under the hood or in the fuse panel inside (not sure). I believe in 97, the TCU moved over to the drivers side above the accelerator pedal.
 
Have you had any luck with this? Mine does the same thing. Works better when the engine is cold, then it's dodgey at running temp and sometimes throws a CEL #45 code. it is a 97.
 
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