Just replaced my transmission in my jeep. It's a '95 4.0 4wd, np231 tcase, and had 30-43LE transmission in it. I replaced it with a used working AW4, which I believe is the same? Anywho, got all my fluids in, DEXRON III 8.0qts in trans, and about 1.5qts in tcase, from empty. Hooked everything up, and it won't go into park, nor any gear. It acts as if it is in neutral. It starts right up, the shifter on the side of the transmission shifts smoothly. Another thing I noticed, is when I run through the gears, it of course doesn't move. It'll just rev up. But when I shift back to park, I hear a light grinding? It seems as if the shifter has too much play when you shift through the gears.

I've attempted to manually shift the transmission as well as tcase to find a park position, but no luck whatsoever. Am I missing something that may need adjusted, or not enough fluids? I'm stumped on it, and my dad has no clue on the situation haha! Any help would be MUCH appreciated!

 

wrong tranny fluid. use ATF+4.

 

No.NotATF4. U did it right. Use Dextron in the AW4!
I expect your fully bolted up to the engine. Does your new trans have all external connections (wiring) made?
Was trans from same year or appear equivalent sittin on the shop floor?
For sure it was workin before u got it? I've had trans (ford) from auto recycler be junk, yes they replaced it but you don't recover the time sweat and blood youve already got into it. Hope someone with more extensive knowledge also responds for you.

 

Do you have flow of trans pump thru the cooling lines??

 

either not enough fluid, wrong tranny, or defect tranny.

this belongs in oem tech

 

Are you sure the t-case isn't in neutral?

 

Yes, it is attached to the engine and flush up against the bellhousing. I was told it was the AW4, I checked between the two. And the only difference I saw was that it didn't have one harness for the tcase. However, I used my old one for that problem. I replaced the filter and gasket too.

As far as year, I'm unsure of that. All I know it was out of a non-renix model year. And I do not know if the pump is operational or not. It came out of a running xj, but the body rotted out on it so it and the engine was pulled.

 

Okay, so I contacted the owner of the transmission I bought. He stated it came out of a 1990. However, from what I've read the '90 was a 21 spline shaft, compared to the 1990.5-96 or somewhere near there, it switched to 23 spline shaft. My transfer case mated right up to the transmission without any issues, had to rotate the output shaft a little bit on the tcase for it to mate up. But it did line up and bolt in without issue.

The transmission I originally had in my jeep was the 30-43LE AW4, and from what I've read on: http://www.novak-adapt.com/knowledge/aw4.htm, it states that transmission is for a 2WD? Mine is a 4WD, how is that possible?

To update the current issue with symptoms, I can shift all transmission gears manually on the side of the transmission without issue, as well as, with it hooked up. When the vehicle is running, in park position, it will shift fine without noise. But when shifting back to park it makes a grind noise similar to this:
http://s130.photobucket.com/albums/p...t=3132bc91.mp4.

The transfer case, will shift through gears manually when underneath it as well as with the lever. But the vehicle doesn't move forward or backward in gear. It just stays in a neutral position, just revving and rolling back and forth when i push it.

 

Your transmission IS working. Your transfercase is not. Engine is running, you put it into drive and the transmission starts turning but for some reason your transfercase isnt. This is how I know. That grinding sound verifies 2 things. Have you ever been driving down the road and into your driveway and accidentally pushed your shifter into park before coming to a full stop? You will hear that same grinding sound until the drivetrain slows enough to allow the transmission to pop into park. The grinding means you have movement in the transmission. You are shifting it into drive, reving it up and the transmission is spinning at whatever RPM. Since you have no breaks on your transmission (only on your axle which currently isnt spinning in sink with your transmission) it will take a while for the the internals to slow to a stop. Usually if you wait a good 30 seconds to push it in to park it will go in without noise. USUALLY. Since there is not a load on the torque converter it could stay locked in even when the engine is at an idle of 750 RPMs. Does that make sense?

 

You said your transfercase shifts? Have you tried putting the transmission in drive while in each gear in the case? Still nothing? My bet is still on the internals of the t case. Did you take the t case apart? What was your problem with your previous transmission? Another test. While keeping the transmission in drive and maybe 1000 RPMs, try to shift the t case through the gears. Do you hear any excess grinding? If so then your t case is trying to shift and your transmission IS supplying power to at least the planetary in your t case.

Stupid question. Are your drivelines hooked up? Can you visually see that the output on the t case ISN'T spinning while in gear?

Also, the AW4 WILL drive without any or the wrong electronics hooked up. It will just start in 3rd so You have to manually shift it and the torque converter wont lock up like it is supposed to.

 

Decided to take off the tcase, and start comparing input shafts on each transmission. Looks like the one I took out was a 23 spline, and the one I installed was a 21 spline.

My question, is there a way to swap out the 23spline input gear for the np231 tcase with a 21 spline input gear out of an earlier model? Is this possible? I'd rather not tear that transmission back out again, so I'd like to go this route if possible!

 

Yes very simple. Just swap the planetaries. Have to tear down the whole case. I didn't know the 21 spline would slip into the 23 spline. It were the inputs different lengths sp they werent even touching?

 

Okay, I'll have to source an earlier tcase and yank that part out!
Yeah, I'm kind of surprised the case even went on with the mismatching of the splines! The lengths between the two were identical, but not the same shaft.

 

Oops I just did this too... I think.

I hate it when that happens.

 

I just installed a 95 aw4 in my 91 xj and having the exact same issues