Question-------------------------
Followup To
Question - The tag on the door says - A43D-
Thanks and regards,
Dallas
My 1991 pu truck w/4 cyl engine, automatic transmission delays shifting into reverse once in a while. It seems to be after I have run the car and left it set for about an hour or so. In about 30 seconds to 5 minutes with the car running in reverse it will engage and run great. There is no slipping and no other gear is affected. I have had it serviced with new fluid and filter and have discussed it with a mech. from my local transmission shop. He says it does not sound like seals or clutches, but, may be a sticky valve. He recommended an additive called casite red and he drained some fluid to accommodate the additive and added it. That did not change anything. I am slightly suspicious of external influences, such as, sensors, vacuum controls and the computer. What do you think is causing this and what can be done?
Answer -
It could be worn clutches, it could also be a valve body problem, I need to know if this is an ECT transmission, try to get the transmission number off the sticker on the door, it should say something like A340, A340H or 340E.
AnswerThe A43D is an hydraulic controlled, overdrive, 2wheel drive transmission, it has no sensors or vacuum controls and the computer has nothing to do with it either.
The shift points are controlled by a governor and throttle pressure but it sounds like that is not the problem, you said it shifts normal and no other gears are affected.
A significant time lag when shifting from neutral or park into revesrse indicates that there is either a problem with the valve body or there is an internal hydraulic leak past a clutch apply piston seal or worn clutches.
There are line pressure tests that can be done that may reveal a low pressure condition, this is time consuming but will give you an idea where the problem may be, for instance if the pressures are normal and it passes the stall test pressures, you can exclude an internal leak and look at other options such as the valve body.
In any case, there will be considerable expense involved.
