Where's my ATF going? ('91 XLT)

[Thallarsen]

I'm guessing that this is a common problem....my tranny isn't leaking, but I'm losing ATF at a pretty fast rate. I have the pinging that seems to be associated with ATF being sucked up into the intake thru vacuum line(s), and the oiliness around the intake 'tree' on the upper manifold.

Assuming that the ATF is going up through the intake, it seems like a common diagnosis is replacing the modulator valve. It also seems like this is not an easy task with too-often poor results.

Any other possible diagnoses, or opinions on modulator valve repair/replacement?

Thanks,
J.P.
'91 XLT
Running great @ 210k but with some pinging......

 

[dzk007]

Replacing a modulator valve is easy but needs to be carefully done. In order to help keep the fluid in the tranny when you pull the valve out, Raise the rear of the vehicle a lot. Have a drain pan handy anyways.
When removing the valve. Be real careful when pulling it out of the tranny. there's a shaft / linkage that must stay put or be very carefully put back in correctly. This is where the job usually gets mucked up. The new valve should have a new seal on it so just put it in like the old came out and hook up the vacuum line.

 

[X-1]

This is an easy repair, you can access the modulator thru the floorboard. There is an access panel near the center. It is alot cleaner and easier this way. Down side is you have to remove seats, and center console to pull carpet back enough to get to panel.