1989 E.B. Bronco 302 with an AOD. Will lose overdrive gear going down the road have to shift in to Drive to keep going. Just serviced tranny not long ago. Any comments will be greatly appreciated....

 

i'd take it to a good shop and have them flush it really good. I've heard many times that when replacing tranny filters, it releases gunk thats being building up on and around the filter, and when you take off after replacing the filter all that crap gets sucked up into the little passagways in the tranny, reducing fluid pressure and causing all kinds of shifting problems and slippage.


Oh but before you do that or anything else check for codes

 

Thanks for the info

 

Actually, the AOD is not controlled by the computer so it will not throw up any codes. Do you mean it is slipping out of O/D? If that is the case it means your O/D band is toast. The O/D band is made of a brake like material and it wears down after a while or becomes burnt. When I rebuilt my AOD my O/D band was just glazed over. It would not slip all the time, but if it was under load it would. I got a good tranny cooler to take care of that. You never want to keep your AOD in O/D under 50mph. Nothing will burn it up faster. Also, when you are towing or pulling steep grades make sure you keep it in Drive.

 

No I don't think it is slipping. With gear selector in OD starting from a stop you can heavy accelerate to 55 mph and tranny will go through all gears. It will cruise at 55 for about 5 minutes with no heavy acceleration then OD disapears and its like the Bronco is in neutral. Then you can shift to drive and then you have all gears to drive. Thanks for the response. Any more info is helpful.

 

Well, that is slipping out of gear. Whe the O/D band gets hot it starts to slip. I would just keep it in drive around town and it should be fine until you need to hit the highway.

 

Is the transmission linkage activated or electronic. Reason why is motor is no longer fuel injected, its carborated. Thanks

 

The AOD is a mechanical tranny. There is linkage running into it. I would also check the t.v. cable adjustment. If that is off it can cause odd things to happpen.

 

Hate to ask but where would that be??? The motor has been rebuilt and in the rebuild we went for more power with the Edelbrock system, carb, intake, cam, bore .30 over.
It rolls on a set of 33/ 12.50 tires. When it comes to the trans I have no clue. One other thing the shift points are all over the board until the trans warms up really good.
Thank you for all your help

 

It is a cable that runs from the tranny to the linkage. If you don't have a repair manual get one. Mine haynes manual tells you exactly how to do it. Just make sure you follow the instructions, if it is done wrong it can burn your tranny up.