Fox T-Bird/Cougar Forums

Technical => Drivetrain Tech => Topic started by: Boss351 T-Bird on June 10, 2014, 12:00:12 AM

Title: AOD reverse problem
Post by: Boss351 T-Bird on June 10, 2014, 12:00:12 AM
I have an issue with my rebuilt AOD. The Forward gears are fine, the Reverse is a bit lazy to engage. The most maddening thing is that the car almost refuses to roll backward. I've removed the driveshaft and checked the rear gears for any problems from my 4.10 install. The rear end is fine going either direction. Turning the driveshaft in the Reverse direction was practically impossible, however. I dropped the shifter all the way down to NEutral and Drive to eliminate the shifter being misadjusted and causing the parking pawl to possible be engaged. The engine was off, so there was no fluid pressure to activate any clutch pack, band, or servo; yet the car is extremely stubborn to push rear ward. Had an episode where something "popped" and the binding seemed to ease up. I'm at my wit's end trying to figure out what might be amiss in the gear train of the trans to bind up like this. I have never had a transmission does this before. Anyone have a similar experience and/or solution? Thanks for any help.
Title: AOD reverse problem
Post by: Haystack on June 10, 2014, 04:49:31 AM
Hopefully where you got it will fix it. Ever aod I've had problems with ended up in the sper. at $1600 for a cheap rebuild at shop rates, I've been junking the car or going to a t-5.

Best of luck.
Title: AOD reverse problem
Post by: TOM Renzo on June 12, 2014, 05:19:59 AM
I actually agree with Stacks. The AOD is by far a very bad tranny by design. Not saying it should act this way it should not. But knowing it's history reliability and performance i would not hesitate to s it and install a 5 or 6 speeder. That is of course depending on if you can drive a stick or there may be other issues for needing an auto. Have a great Thursday guys. 

Note i am not an auto TRANNY  guy and have limited experience with them. But i do know the tranny when in reverse either uses first along with reverse in some manner. I was told this by my Tranny guy years ago and reverse is the hardest gear to set. Not 100% on this as i have limited experience with that tranny. But i do know the Throttle cable has to be adjusted properly by using a gauge and reading line pressures. If that is not set properly you can smoke the tranny in short order and it can effect reverse i think. I am willing to bet most of those trannys do not have the throttle cable adjusted properly. And the flimsy linkage and throttle linkage ratio must be dead on. I learned this when we were replacing Variable ventury carbs with conventional ford carbs. The linkage hand lever ratio has to be dead on for it to work properly. We normally use C6 trannys and 400 and 700R4  Turbows on chevys and of course 727 Torque Flites or load Flites on mopars. I think you should contact the rebuilder on this issue and see what he says. Good Luck
Title: AOD reverse problem
Post by: MechanicMatt on June 12, 2014, 09:30:20 PM
Tom NOBODY in my family is a Automatic guy, but Pops had a 67 GTA that they pulled the 390 out and put a 428scj in.  He said that no matter what he did to that car the C6 NEVER hiccuped, sneezed or coughed.
Title: AOD reverse problem
Post by: Lodemia on June 13, 2014, 08:21:42 AM
Quote from: TOM Renzo;434752
Note i am not an auto guy and have limited experience with them.

i'm new to the site, and I read this as "I'm not a car guy."  And I thought if Tom is saying he's not a car guy, then what the heck am I doing here!? It's funny when you misinterpret it.
Title: AOD reverse problem
Post by: TOM Renzo on June 13, 2014, 08:36:35 PM
What i meant i am not an AUTOMATIC TRANNY GUY. MATT the C6 is so dam strong i have in the almost 47 years in business ever seen one fail. That includes trucks as well. Only problem they are not an OD unit. Have a great weekend guys!
Title: AOD reverse problem
Post by: turbotrav on June 25, 2014, 11:24:02 PM
4R70W....?????

Travis
Title: AOD reverse problem
Post by: TOM Renzo on June 26, 2014, 08:05:38 PM
4R100 is a better tranny according to my go to tranny guy. I personally as i said not a tranny guy but from my guy the 4R70 is a very weak unit. Once again very limited on auto trannys. C6 the strongest but no OD so if you cruze the highways they are out unless you run a low ratio final drive. have a great evening guys.
Title: AOD reverse problem
Post by: Boss351 T-Bird on July 28, 2014, 12:01:47 AM
Turns out I had a "too thick" thrust washer between the pump and the intermediate clutch...... you live, you learn.......just because two donor trannies used the same thickness washer doesn't mean that you can safely assume that the component stack height will be within the same window and allow you to forego measuring that clearance. It's weird how the trans will turn Forward with ease, but totally bind up when you turn it in the other direction.
Title: AOD reverse problem
Post by: Haystack on July 28, 2014, 01:15:46 AM
Glad ya got it figured out.
Title: AOD reverse problem
Post by: 1BadBird on July 28, 2014, 07:37:44 AM
Boss351, what part of Texas are you from??
Title: AOD reverse problem
Post by: Boss351 T-Bird on July 28, 2014, 08:28:42 PM
North of Amarillo......... up here on the Caprock......... I'd have to tow to Wichita (KS or TX) to get some good air...... LOL!  I see you have a '86 'Bird....... Have you done any research on the fit of aftermarket K-members for an '86?  Man, I could use some working room around the Hedman's on my 351C. They have flat collectors and you can't even pull the trans pan without dropping the passenger side header off and knocking the collector off the driver's side.