Help with 91 AODE/4R70W conversion ,Rebuilder Welcome...

ecyrbh

Registered User
This is kinda long,so here goes...I have a 91 SC that I have converted to a AODE/4R70W...The best description of my issue is on initial startup,I back out of my garage,then drive half a block,..trans is in 2nd gear by then and I turn a 90° corner...I accelerate out of the corner and the trans neutralizes...I coast to the curb and come to a stop,put the car neutral or park and then I shift to any other range and no engagement...nothing...the idle may be elevated slightly,at times when it neutralizes, but after a few seconds,I will get engagement...This may happen once or twice,but after it warms up,it absolutely shifts flawlessly ..The trans is a fresh rebuild with less than 100 miles on it...TransGo shift kit and PCS(POWERTRAIN CONTROL SOLUTIONS ) stand alone controller..The trans is supposed to be a 96 or 97 unit...Please,any advice is appreciated
 
Wrong dipstick &/or tube ?

If wrong tube or dipstick combo was used during swap, it may indicate fluid
is full, when it is actually low.
When you take that first turn, fluid runs away from pick up.
Once it warms up a bit fluid rise's enough to maintain pressure.
Just a thought.
 
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Good morning


Check fluid level as DOUG H suggested. May need to install 4R70W filter and pan. The pan will have a dimple for extra fluid capacity when making turns. The filter has a pick tube to match.

Could be as simple as the replacing the filter and pan or the filter clogged.
 
The pan on this unit is a stock depth cast aluminum pan without the sump...If I recall when i installed this trans,I have 11 qts of fluid in it...The "Add" mark is level with the case or gasket surface...I just can't imagine that it is low on fluid or being starved for fluid because i intentionally overfilled it and have the same issue as described...I did however use the original AOD dipstick and tube on the install...I've changed the EPC solenoid,with no change
 
It's a Flash page; you may need to use Internet Explorer or FireFox to view it.

Or enable Flash for that page in Chrome.

RwP

Still won't load for me..Three different computers and same thing...I tried Chrome and Flash...Don't have Firefox anymore,I had issues with it...Can you tell me the jest of the article please...
 
tccoa non-flash articles are here:

https://www.tccoa.com/articles/tranny/index.html

...no idea if they will help w/your issue(s).

Screenshots of the flash page:
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I noticed the suggestion to use a scotch-brite pad...something I would avoid, and keep away from any engine or transmission, as they contain very small aluminum strands that can easily remain behind after repairs, acting as an abrasive and risking damage to otherwise fragile surfaces/components. Don't think you can simply wipe or clean them away. Better to find other materials more suited for the task.
 
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I'm going to take the advice of Doug H and Sam Jones and replace the cast aluminum pan with a 96 steel pan and filter with the deeper sump/tube...If I can source a matching filler tube and dipstick,I'll be doing that too....I currently have the valve body out to inspect and thoroughly clean,just to ease my mind...I hope it's just the transmission breaking in,but during the cleanup,there is a little bit of " pixie " dust coming from the valve body.....Brass or Bronze in color along with what looks like aluminum dust...none of it is magnetic...Any thoughts guys???
 
Can someone please take photo of a 94 or newer dipstick tube to show how it looks under the hood and give me the length of the dipstick ...According to Ford,94 and newer AODE/4R70W use a different part # than a 91 AOD..Maybe a difference in length or full level marking may help me out...
 
Can someone please take photo of a 94 or newer dipstick tube to show how it looks under the hood and give me the length of the dipstick ...According to Ford,94 and newer AODE/4R70W use a different part # than a 91 AOD..Maybe a difference in length or full level marking may help me out...
You could just try overfilling 1/2 quart at a time to see if it makes any difference. You're not going to hurt the AOD with 1/2 quart extra fluid. Worst thing that will happen is it will leak out the back or the top vent cap. That might just fix up your stalling issue.
 
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