A4LD rebuild gone bad. Need help. (slipping, shuddering)

[Amac]

Background - 1994 4.0/A4Ld with 190,000 kilometers. Last December I took my tranny out and rebuilt it due to the intermediate band failing. I replaced all seals and clutches, left the steels and added a SK-A4LD-jr shift kit..

I've had problems ever since, but today they got serial.. When I first put the trans in, I had no overdrive and the 1-2 shift was a wee bit delayed seeing as I installed a shift kit.. The big thing was the RPM flare on the 3-2 downshift . I'm guessing that I marked a valve causing it to stick in the valve body.. I pulled the valve body off 4 or 5 times trying to diagnose why I had no OD trying different things, double checking my steps, etc, etc.. Still not fixed..

Anyways, I was living with that since I don't do much highway driving with it, but today, I cam to a stop and when I took off it shuddered real bad and was now flarring on the 2-3 shift.. Now both 1st and R require lots of RPM to get going, but once going, seem OK.. (except for the 2-3 flare)..

Kind of wondering if maybe the fact that I didn't change my converter when I did the build has anything to do with it.. I have half a mind to get a virgin valve body and put it in..

I've been searching for answers and am going to continue to do so.. Any suggestions would be greatly appreciated.

Cheers,

 

[Amac]

Oh, and one other thing, I did not pull the front pump apart.. I know, I know...

Cheers,

 

[toy720]

when you did your last rebuild you used the old converter how much trash did you have in the pan. when you took it off if you had alot of trash (band lining,metal.clutch lining etc...., and you reused the tc that could be a problem because you can not totally get the old tc cleaned out so therefore it would go right through the tranny on the rebuild? that would be my opinion.

 

[Amac]

Thanks for the reply.. The only thing that I found in the bottom of the pan was the broken part of the intermediate band.. No shavings or foreign objects.. The fluid was pretty black though.. That was partly why I didn't change the converter(no filings), and also I'm cheap...

Cheers,

 

[Glacier991]

I think you would benefit from putting a pressure gauge on it..... I am thinking low line pressure is a root issue here.

 

[Amac]

Hrm, don't think I have access to a psi gauge that goes that high.. I'll have to try and source one, I think it would be an invaluable diagnostic tool.

Thanks!

 

[BrooklynBay]

Did you flush out your cooler? It could be partially clogged. Your solenoids could be clogged too. Did you clean them out, or replace them when you rebuilt it?

 

[Amac]

I didn't replace the OD or lock-up solenoids on the VB during the rebuild, as they were working when I took it apart.. I didn't go so far as to flush the cooler, but I did put shop air both ways through the lines/cooler..

Thanks!

 

[BrooklynBay]

There is a spray can called cooler cleaner. It's a chemical cleaning agent that is designed to flush out the cooler. Here is the inforamtion: M465KD Transcool cooler cleaner spray ($7.09).

 

[Amac]

Well, guess what! I was going to take the truck to a guy I know that owns a transmission shop, but on the way over, it went back to working the same way it did after the rebuild.. Only thing I can figure is that it must have been a peice of dirt or something that got caught up in the valve body..

Either way, I pulled the valve body and am taking it to him tomorrow to let him go through it and to make sure that I put the shift kit in correctly.. I imagine that is where I messed up..

I'll report back with my findings..

Cheers,

 

[BrooklynBay]

Before you reinstall the valve body, remember to clean out the spring in the underside of the transmission case. The spring acts as a filter. Here is a picture of it:

 

[Amac]

Ahh, yep, I was inspecting that after I removed the VB.. I'll make sure to remove, clean and reinstall before installing the VB..

Thanks!

 

[Amac]

Alright, so I took my VB to the tranny shop today and a couple of guys took the seperator plate off and checked a few valves.. They said everything looked fine and couldn't find any problems with it.. (even the shift kit springs and what-not)

Anyhow, I decided to break down and buy an in-lbs torque wrench this time around since it's really hard to use a ft-lbs wrench for 7lb-ft of torque (~84in-lb).. So I put the VB in, torqued everything to exact spec, and guess what..

Everything works! OD works, no 3-2 flare, it all works like it should.. I was starting to think I was going to have to pull the whole thing out and go through it again..

So let this be a lesson to anyone rebuilding their tranny, torque specs on the VB are very important.. (Duh! I guess.. ha ha) Even the shift kit instructions said that a "no OD" condition could be caused by VB bolts being too tight.. It's also possible that the tranny shop dislodged some dirt, or free'd something up..

Either way, it's fixed!

Thanks for the input guys, much appreciated!

Cheers,

 

[Glacier991]

An excellent lesson here. A FT LB TORQUE WRENCH AIN'T GONNA CUT IT IN TRANSMISSION WORK.

These VB torques are critical, especially the evenness of application of torque.

For those wanting to know more about torque wrenches, there is an excellent thread on them in the "Garage and Tools" Forum.

Thank you for updating us. You made the point better than I ever could have!

 

[BrooklynBay]

Thanks for letting us know about your successful experience. This will help out a lot of people here. What brand torque wrenches did you use both times? What drive size were they?

 

[Amac]

First time around was a Snap-On 3/8 ft-lb wrench, and this one is a Mastercraft Maximum series 3/8 in-lb unit (25-250 lb/in)..

There is nothing worse than finding a thread describing the same problems you have, but no solution.. I just posted a new thread over in the underhood section about my detonation fix/solution.. (clean your MAF)

Once I get all this stuff sorted out, I can start a turbo instal..

Cheers,

 

[toy720]

glad to here it was something so simple as torque specs i guess that just goes to say how serious specs are, i believe more and more each day.