89 XR-7 - transmission won't shift

You're right about all those tiny notches...

Note this link on AODs from B&M: http://files.dpbrands.com/bm/instructions/114501.pdf

5. AOD transmissions are extremely sensitive to proper Throttle Valve linkage/cable adjustment. Proper adjustment of
this linkage/cable is the most critical step of your installation. BE SURE TO CARE- FULLY READ THE INSTRUCTIONS IN THIS MANUAL THAT RELATE TO THIS ADJUSTMENT!


See this thread for discussion:

http://www.sccoa.com/forums/showthread.php?30511-TCCOA-TV-Cable-Adjustment

'baking' a trans, of course, means heat. The cable controls pump pressures. Pump pressures are used to tighten or release bands. A band that should be tight when it's loose will slip and generate heat. A band that's tight when it should be loose can force the drive train to power thru it, causing heat. It doesn't take long to fry a band, drum etc. in either case.
 
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Running a can of additive which will clean up the valve body, at this point, is a good idea. Certainly can't hurt. But do it before you change the fluid and filter.

The issue with the disconnected TV cable is that is allows a drop of pressure overall, and results in more slippge+heat. Thats what bakes the friction plates, especially the frictions in the direct clutch. If it went on for a long time, you'd pretty much have to rebuild the trans. But you'd have worse issues from what you describe. There would noticable slippage, failure to upshift, etc.

Overall, about as much as you can do is to attach, adjust, change fluid+filter and if its driving OK, live with it. Anything further requires a rebuild. I learned how to do that years ago, but theres a learning curve and to overcome the mistakes you'll make, you have to be prepared to remove and install a few times. If you've got the determination to take it on, buy the chilton book on AOD transmissions, at every car parts store, and good luck. :cool:
 
Running a can of additive which will clean up the valve body, at this point, is a good idea. Certainly can't hurt. But do it before you change the fluid and filter.

The issue with the disconnected TV cable is that is allows a drop of pressure overall, and results in more slippge+heat. Thats what bakes the friction plates, especially the frictions in the direct clutch. If it went on for a long time, you'd pretty much have to rebuild the trans. But you'd have worse issues from what you describe. There would noticable slippage, failure to upshift, etc.

Overall, about as much as you can do is to attach, adjust, change fluid+filter and if its driving OK, live with it. Anything further requires a rebuild. I learned how to do that years ago, but theres a learning curve and to overcome the mistakes you'll make, you have to be prepared to remove and install a few times. If you've got the determination to take it on, buy the chilton book on AOD transmissions, at every car parts store, and good luck. :cool:

Engines I can build....transmissions I've always left for the pros.....too complex and expensive to risk a mistake.

I'm starting to consider taking it to a tranny shop to get the fluid, filter, diff fluid change and TV adjustment done with the pressure gauge instead of me adjusting until it feels right. The adjustment doesn't scare me too much, but we just got our first blast of snow (I live near Buffalo if any of you were watching football on Sunday) and I REALLY don't feel like laying on a wet, cold garage floor trying to get 80/90 to drain from the diff and hoping I don't screw up gaskets because I'm trying to do it lying under the car. I guess I'm just getting old. Years ago I would have done it in a t-shirt! Lol

We'll see....if I can get it shifting nicely maybe I'll put in the additive for the valve body and do the diff now because the shudder is pretty bad....am I doing damage or is the slip simply not working?
 
Hey all...

I promised an update but it's been so damned cold here that I haven't worked on it much, but I DO have an update.

I changed the fluid in the diff, and changed the fluid and filter in the tranny.

I did NOT drain the fluid in the TC during this because I couldn't get the drain plug to break free! Ended up f'ing up the corners on the bolt after messing with it for so long and finally gave up.

When I filled the tranny I put a couple bottles of Lucasoil additive in it, then I started messing with the TV adjustment.

I finally got the adjustment to a point where it shifts through all 4 gears, at reasonable RPMs. However, it doesn't want to shift into 3rd when it's still cold. After it warms up fully it will shift.

At this point I'm sure there is some wear/damage in the tranny or AT LEAST the throttle valve. It's driveable now which is great, but I don't think I've seen the end of this work.

All I have is theories as to why it won't shift when it's cold, and those theories are a) sticky throttle valve, b) wear/damage in the tranny, or c) something wrong with the TV cable besides the adjustment.

Thanks again for all the great information and suggestions here....and if anyone has any thoughts on troubleshooting the cold shift problem, I'm all ears (eyes?). Other than the cold shift problem, it runs nice and smooth at this point....oh, and no more shuddering. Turns out the shudder wasn't from the diff, it was from the tranny not downshifting at stops or near stops. The TV adjustment took care of that.


On a completely unrelated note...I'll be looking to upgrade some things on my 92 SC in the spring, and I was wondering if anyone has found custom headlights....or made their own using the factory shells? I'm also going to be looking for some nice 18" rims....preferably black but if the price is right I'll get them powder-coated myself. Any suggestions on offset or where to find rims for a good price (used?) would be appreciated, either here or PM. I see Bill has some nice ones coming in...might just have to save my pennies for those because they're EXACTLY what I'm looking for.
 
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