Hey, I have a question about my transmission. I have a 1992 aerostar 3.0L 4 speed auto 119,000 miles The trans started leaking the other day and I found out where it is coming from.



Can anyone tell me what this part is called and how to change it. I plan on putting some stop leak in there and I hope that stops the problem. Also I already changed the pan gasket because i thought that was the problem, but as you can see it is not.

 

No picture showing. Try again?

 

It looks like it is coming out of the circular thing.

 

I dunno. It looks more like a pan gasket issue with the fluid merely accumulating at the round item. I'll be looking for your post to tell me if I'm right or missed it totally. Let us know.

Dave

 

I had the van running and i went under the car and saw that the fluid was dripping from the circle all over the pan (which made it look like the pan was leaking) as i wiped around the grooves of the circle, the fluid kept coming out of it. I dont know what that thing is, but I read that it might be connected to the pump.

 

I think you might be right. I'm not sure if those circles are test ports or it they are where the solenoids are. They should have gaskets and my guess would be that the gasket has failed. Those circles are so close to the exahust that the rubber just turns brittle from the heat.

 

That's the overdrive servo cover. I think I have an exploded view somewhere, from when I helped someone else on FTE with a leak there . . . yup, here it is (a blast from my past):

(click on any image for larger)


Here's the thread in 2002 where I originally posted about this. The forum's software has changed in the meantime, the URLs are screwed back then, nothing I can do about it now.

You will want to burn up half a can of cheap aerosol carburetor cleaner on that whole area, drive a few miles (in overdrive, so get up to highway speed), then look there again. You might find that the fluid is coming from further forward (for example, the torque converter seal, or the pump o-ring).



Those servo cover o-rings are typically square cross-section. I cannot imagine it being more than $5, probably $2.

If you decide that's your leak, clean the area, pry out the wire ring while holding in on the cover (there's a big spring under it), then if the cover doesn't fly out at you, tap it lightly (tap, not bang), and it (and a cup of ATF) will pop out.

Judging from the color of the ATF that's leaking, you may want to consider flushing the ATF and changing the filter. You changed the pan gasket, but most of the ATF is in the torque converter, so your new 2.5 qts of ATF is diluting the remaining five quarts of old fluid left in the TC. Looks ugly. For a light recounting of how I flushed my '93's a month ago, see this post.

HTH

 

Asavage,

You are dead on. There is an O-ring on the servo cover, and I guess that's where it's leaking from. The servo is only held by a retaining ring. The O-ring is actually round, and you can buy it from any tranny shop for a few dollars. Don't even try Autozone or Kragen since they don't carry it.

 

I'm not seeing a picture either, but do you have the heat shield in that area? It's attached to the transmission with a spring clip clamped to the pan ridge and a bracket that's bolted to the side of the transmission. It sits between the transmission and exhaust pipe (and maybe catalytic converter) that runs right by that area.

 

some one has been prying or working on that servo recently
can see deep scratches into the aluminum from a pry tool on the rear inside

take the servo cover to auto tranny shop to get the right size cover seal and replace the servo piston seal at same time. examine closely the piston and bore for corrosion and scratch damage. do the intermediate servo behind the OD servo also, seals will be shot in it
looks like an AB size from cover marking 2.075 inch ID cover

put a light coating of ATF or petroluem jelly- Vasoline, used by many auto tranny shops for assembly lube, in bore on piston and seals prior to assembly.

 

COMMENT REMOVED.

 

I have only seen that clip-on heat shield on 4.0l-equipped Aeros. I don't think that any of my Aeros have had that heat shield (but I may be mis-remembering). Certainly, my '89 did not -- I had its trans out enough times to know!

 

Caution: Although it was mentioned, to clean the area around the servo bores, be sure to thoroughly clean it before replacing the new seal. Over time, a thin "crusty rim" from road salt deposit can form on the transmission case below the servo cover. It almost looks as if it is part of the T. case casting but obviously is not. While you can pull the old seal past this small rim easily, the rim is rough enough to ruin the tender edges of a new seal. Use a #400 grit paper to ensure any deposits are removed. If someone had recently opened your servo cover, the seal may have been damaged in this fashion.

 

Thanks for all the feedback. I know for sure that nobody has ever messed with it in a shop since i cant even remember the last time i had this Aerostar in one. Unless someone crawled under it and just started messing with it. My guess is that the O-ring around the servo piston has failed due to harsh weather here in Chicago, and the fact that this van has never seen a garage in its life. How hard is this to fix? I CAN take it to the local transmission shop, but don't want to if it is an easy thing to fix.

 

Hardest part may be access. If you don't have enough room, you'll have to drop the wye pipe (unbolt it from the exhaust manifolds). On my 89, you had to also remove the trans crossmember to get the wye pipe out, but your '92 probably has the stainless flex exhaust coupling at the rear of the wye pipe, and trans crossmember removal may not be necessary.

But in your part of the country, getting the wye-pipe-to-manifold nuts off may be a challenge, with the corrosion. If one exhaust stud breaks, you will not be happy.

If you have enough room to get to that servo cover, follow the advice of myself and others above. If you can get to it, it should come off relatively easy and the o-ring is cheap.

If you have to pay a trans shop to do it, and if they have to remove the wye pipe to gain access, it will run a couple hundred bux, IMO.

First things first, though: clean off that area and test drive to make certain that that is where the leak is. Fluids in cars have a way of moving around and it's awfully easy to misdiagnose a leak.