There's no bad exhaust.. I thought it was oil.. I guess it could be anything... there were definitely wet spots on the back of the van.. could this be transmission fluid?

 

ATF is a low viscosity lube that is pressurized to in excess of 100 psi in an auto tranny. can spray out in a very fine atomized mist that coats everything and flys up in the vacuum of the van rear, coats back end.
seen it often in pickups that blow out or puke out ATF from a tranny overheat on a mountain pass. coats the trailer in ATF. add some dust and we have mountain soup.

is your ATF or engine oil level dropping?

never seen an A4LD that didn't seep, leak or dribble some ATF.

if the rig has been setting for several years, all the gaskets and seals have dried out and cracked. going to leak like a sieve until gone thru and all replaced, tranny and engine. the crank seals develop flat spots from long sets, only solution =s replace. same with most of the large shaft seals in the tranny.

 

I need to check the fluid level.. but the tranny puts about a quarter size spot every time it's driven (sometimes bigger) on the ground.. the oil spot is even bigger.. I'll keep everyone posted!

 

Well.. the Star is back to the shop this week! After one week at the mechanic I found out that the engine is dry of oil with the exception of the rear seal. Also found out the transmission (the NEW transmission) has a bad leak where the linkage goes into the transmission. Last night, I took it for a quick spin (it had been a while) and it would not shift out of 1st gear for about 3 miles.. then had a hard shift into second and shifted normally after that. Sounds like the transmission shop is going to have some work to do! And just for funsies.. now the check engine light comes on when the engine has warmed up! Someday she'll be back up to par!! I'll keep you all posted!

 

It may be premature.. but got the Aero back from the shop today. Drove it home... let it sit.. and went to check.. no fluids of any kind!! The transmission shop replaced the rear seal again, and the seal where the linkage goes in the transmission.. he called it the manual seal I believe... so far all is good.. now off to the suspension and brakes!!

 

the shift shaft seal into the transmission is a very weak wear point.
the case shift shaft hole wears egg shaped oval making new rubber seal worthless. common failure weakness in A4LDs driven in town short trip driving

there is an attempt at a repair mod with inserted brass bushing in the old threads here. search several years back
may also find the shift shaft leak repair over on the Ranger/Explorer forums.
lots of good auto tranny repair info on the site
http://www.explorerforum.com/forums/

 

Shift shaft seal...say that 10 times...really fast.

 

Hey guys.. just an update!! Still leak free!!! Just had the suspension redone.. sway bar links, new wheel bearings, control arm bushings, upper ball joints and control arms and new shocks. She's riding great now! Also had the brakes redone-- needed new calipers on the front (they were leaking), rotors, pads and the backs cleaned adjusted, etc. Now all I have is a couple loud pulleys, tires and some exhaust work!! She's almost there!

 

Ok all.. I'm at a loss!! Got the aerostar back from the shop for the suspension.. took it for a drive and all was good.. took it down to the car wash to sweep it out and took the long way home.. anyway.. while turning left I heard a loud pop sound. I thought it was something in the road.. but now she's leaking worse than before.. looks like the main seal again!! This would be 3 main seals in 200 miles.. what can be causing this?? What do I need to do??

 

plugged PCV system, valve not working....plugged vac. line to PCV valve.

or broken/worn rings

either causes excessive buildup of crankcase gas pressure.

 

would a clogged cat converter cause this as well?

 

A clogged cat will not cause an oil leak.

But I would worry about the pop noise. If it's really from the rear main, it could be due to main bearing wear, allowing it wobble, or badly installed transmission, though I'm having a hard time imagining it.

The other cause of repeated rear main seal leak is from wear on the crank shaft surface that the seal lip seals against. Fel-Pro makes sleeves that can be installed over that to give the seal lip a better surface to seal against. Or you can try to find one of the new teflon seals that can conform to the shape of the shaft. But you have to use its installation sleeve, even if you remove the rear main bearing to help install it.

 

I guess I'm a little out of my element.. how easy is it to diagnose where all the backpressure is coming from? If it is a worn main bearing.. doesn't that mean a rebuild? Maybe this is why it still has a loss of power sometimes and a rough idle?

 

You can try replacing the PCV valve; it's not very expensive, but it may require some contortions to replace it.

On most modern engines, there should be a PCV valve on one valve cover, and an air inlet on the other (or on two sides of a single cover), to allow air circulation. As such, it's not easy to pressurize the crank case, unless you have really bad blow-by in the rings.

 

how can you tell if you have ring blow by? I don't want to replace the PCV valve and the rear main again only to have it blow out again...