PCA Forums

ok, the automatic tranny in my 88 econoline has quit being fully automatic. it is not upshifting where it should, and sometimes not at all. I can manually upshift 1>2 with no prob, but have to get it to about 50 before i can 2>3. It does downshift by iteslf, but is not smooth. The fluid was a little low, I put some in, but it doesn't seem to make any difference.

this started after the car was parked for 3 days (and it was raining). before that it was fine.

I'm a little hesitant to take it anywhere b/c i know that trannies can mean big bucks, and while this WV SUV has only 177k on it, It has other issues and I don't want to get into any big repairs

btw, the mechanic who replaced the brakes about 1 year ago told me the axle was grooved and would probably not last more than 10k (that was about 8k ago)

any ideas or thoughts appreciated. trannies are definitely not my thing.

TIA

Sounds like a bad vacuum modulator. Not sure if Ford went to an electronic modulator in '88.

I think it was electronic in 88, unless it's still a C6. If it's a C6, do have the regulator checked, and look into a flush and new filter. If it's the E4OD, maybe a filter change and fluid flush will help, but in all likelyhood it probably needs a rebuild.

ford were still using a C6 in 88 so it should be running off of vaccum. Either a vac hose has came loose or that part nas mentioned is out...

E4OD might have been 89, then...

edit: got it. If it's a 3-speed (no overdrive) it's a C6, if it's overdrive it's an AOD.

I think it was 90 when the E4OD first showed up. A buddy has a 89 F-150 and it still has the C6 in it. Hard saying though.

sorry... cant be of any help... all i know about is TH-350, TH-400, power glide and 700-R4

i need a 700R4 for my truck i hatethe TH350 thats in it now...

Originally posted by wvjohn
ok, the automatic tranny in my 88 econoline has quit being fully automatic. it is not upshifting where it should, and sometimes not at all. I can manually upshift 1>2 with no prob, but have to get it to about 50 before i can 2>3. It does downshift by iteslf, but is not smooth. The fluid was a little low, I put some in, but it doesn't seem to make any difference.

this started after the car was parked for 3 days (and it was raining). before that it was fine.

I'm a little hesitant to take it anywhere b/c i know that trannies can mean big bucks, and while this WV SUV has only 177k on it, It has other issues and I don't want to get into any big repairs

btw, the mechanic who replaced the brakes about 1 year ago told me the axle was grooved and would probably not last more than 10k (that was about 8k ago)

any ideas or thoughts appreciated. trannies are definitely not my thing.

TIA

Did you try to replace the pan and screen? In the tranny?
It's on the bottom of the tranny and can cause alot of problems.This is the pice that filters the trans. oil.
Also check the flo through the coolant line to ensure that the circulation to the radiator is to spec.
Bill

I had a similar problem on my 89 Buick. Turns out it was a vacuum modulator. It was like a $5 part and took removing a single bolt that was right on top. According to my dad it was the easiest thing he had ever changed on a car.

thanks for all the feedback!

I went out and inspected the hoses that come up from the engine area to the air cleaner area and found one disconnected, put that back on and also repaired another hose fitting that goes to the air cleaner assembly - it also looks as though my "assistants" who helped me put the new air filter in last week lost about 3 of the screws that hold the air filter holder assembly together -

on the way to work it did upshift by itself, but still at a higher than normal rpm, but without blowing the engine up - is the vacuum the trannie uses dependent on a tight seal on the air filter assembly? if so I'll pick up a roll of duct tape

btw it is a 3 speed

got to do a little work now , i'll report back later

I just happen to have one that was pulled from a van... its still good. the engy locked up on the van. It was an astro. Would be willing to sell it. hell.. actually i have 2. that one and the one thats on my old caprice.

Yeah its a C6 tranny then wvjohn... If there is a vaccum leak that can affect how it shifts. either replace some hose or duct tape works wonders lol i think that is all that hold my old 72 chevy together... that and the bowtie on the front i pray it never falls off or the rest of the truck will fall apart with it...

heavy rain today so there won't be much mechanical foolishness - i'll check for leaks an bad hoses when the weather clears a litle bit