Skip to main content
Topic: No reverse (Read 1256 times) previous topic - next topic

No reverse

All I did to the transmission is drain the fluid, put in a new filter and gasket. I put in 5 qts. of transmission fluid and started the car in idle and added fluid. Now it reads full when running and I get forward but not reverse. Vacuum issue?

No reverse

Reply #1
Did you remove the old gasket on the valve body before you put a new gasket and filter on the valve body? That might cause a problem. Sticking parts in the valve body could cause problems as well. It can't be a vacuum issue, as the AOD is not vacuum controlled at all.

BTW what fluid did you use?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

No reverse

Reply #2
I wouldn't be able to tell you where the valve body is. I take it there is a gasket I should have removed and replaced? All I did was pull the old filter off and replace it with a new one, then changed fluid with Valvoline Dex/Merc Max life (for transmissions over 75,000 miles). I did disconnect the bracket for the transmission linkage when I jacked the engine up, but it is bolted back on to the frame. If I need to get back into the transmission, I'm going to have to figure out a way to save the fluid. I have used 9 quarts @ $8.27 a quart. Thanks!

No reverse

Reply #3
The trans filter bolts to the valve body. There is a little square gasket that goes between the two. If you don't remove the old one and install the new one over it or don't use any gasket between the two the trans pump will suck in air instead of fluid. This can cause a bunch of weird problems.

It's also possible that the shift linkage may be slightly off so you can't shift into reverse. Try and see if you can feel the shifter kind of "click" into each detent. It's easier to adjust the linkage than drop the pan looking for problems.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

No reverse

Reply #4
It doesn't sound like there is a lot that can go wrong with an AOD transmission. It was getting dark when I started up the car last night and I was more worried about smoke coming out my exhaust. What I did notice when I was shifting gears was a lack of "click", it just seemed to slide over.  I will go see what I can find out and get back with you. Thanks!

 

No reverse

Reply #5
Somebody upstairs is obviously looking out for me! A couple of days ago I happened to find a small clip. So, not knowing what it was or where it came from, I put it on another bench just in case I figure it out later. Well, later is now. It is what holds the adjustment to my transmission cable. On another thread I said that my adjustment for the throttle cable seemed to be off and I had to change springs to make it adjust right. So, now class is on again.... I need to go understand my cables and their adjustment. That's actually a good thing, because I want to change mine out with a "Lokar" set up being mine has a plastic part that's broken (not good).