A4LD Trans problem, need help please!

89 Aerostar; blown seal after shifting problems noted, then slippage then blown front seal. the trans had seemed to 'hunt' while in cruise, prior to event.. feel shifting sensation with change in engine rpm.

Installed used trans, sensitive to the 'hunting' sensation.. some small indication of same but nowhere near the extent of previous, otherwise shifted fine EXCEPT a couple times where slight 'tip-in' resulted in shift-up, rather than down. Otherwise trans shifted well and solidly. No thump,, no hesitation.

BUT front seal blown again in 65 miles.

What I might have done wrong: Did not replace front seal, showed no wear on pump collar. or evidence of long term leakage in bell hsg

Did not mount TC and check for run-out prior to install

Did not check for pilot bush integrity

Re-used the VSS on the van, instead of the one that came with the salvage yard trans.

- - - - - - - So it comes down to either a mechanical problem... or a bum VSS. I have seen a hint on web research that inop VSS happens at same time as blown front seal.. so they may be related. In one of those there was a cryptic ref to high pump pressures..

BUT; this is an 89, not one of the later versions where the PCM controls everything, right? Will a faulty VSS in this series result in PCM trying to engage two clutches at once? And does that result in the symptom.

What I did right:

Stopped as soon as possible when I noticed traili blue smoke... trans did not slip or otherwise act up, so I may have saved it. Though I'm obviously going to have to get a new TC.

AND YES... I am kicking my own arse, well and often for short-cutting

So, does anyone here with expertise have advice? I cant afford a full rebuilt at this time.

DOES THE VSS cause this? (Cruise didnt work either natch, but hadnt for at least 25,000 ) And how much can I expect to spend for the TC?

Reply to
Backyard Mechanic
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Also need to learn to proof read twice before posting, CORRECTIONS:

89 Aerostar; blown seal after shifting problems noted over period of about 150 miles, then slippage then blown front seal.

- the trans had seemed to 'hunt' while MAINTAINING CONSTANT SPEED, THIS FOR ABOUT A WEEK prior to FIRST event.. could feel shifting sensation with NO change in engine rpm.

Installed used trans, drained, filter replace, filled, checked fill again, sensitive to the 'hunting' sensation.. some small indication of same but nowhere near the extent of previous, otherwise shifted fine EXCEPT a couple times where slight 'tip-in' resulted in shift-up, rather than down. Otherwise trans shifted well and solidly. No thump,, no hesitation.

BUT front seal blown again in 65 miles.

What I might have done wrong: Did not replace front seal, showed no wear on pump collar. or evidence of long term leakage in bell hsg

Did not mount TC and check for run-out prior to install

Did not check for pilot bush integrity

Re-used the VSS on the van, instead of the one that came with the salvage yard trans.

- - - - - - - So it comes down to either a mechanical problem... or a bum VSS. I have seen a hint on web research that inop VSS happens at same time as blown front seal.. so they may be related. In one of those there was a cryptic ref to high pump pressures..

BUT; this is an 89, not one of the later versions where the PCM controls everything, right? Will a faulty VSS in this series result in PCM trying to engage two clutches at once? And does that result in the symptom.

What I did right:

Stopped as soon as possible when I noticed traili blue smoke... trans did not slip or otherwise act up, so I may have saved it. Though I'm obviously going to have to get a new TC.

AND YES... I am kicking my own arse, well and often for short-cutting

So, does anyone here with expertise have advice? I cant afford a full rebuilt at this time.

DOES THE VSS cause these symptoms and result?? (Cruise Control didnt work either, natch, but hadnt for at least 25,000 prior to any indications of fault) And how much can I expect to spend for the TC? {added} Or am I dealing with a rare case of faulty PCM?

-- - - -- Also noted: Some slight indications of 'surge' in idle/Park or stopped in gear. But vac modulator clear and no leaks. As I said smooth no-hesitation shifting noted.

Took care to properly align detents to shift lever, verified kick-down cable free to adjust and lever moves freely. And, as noted, used MLPS that came with used Trans.

Reply to
Backyard Mechanic

Torque convertor going in/out of lockup? Could be bad trans computer.

Did you re-use the old TC?

-LMB

Reply to
Louis M. Brown

Louis M. Brown

Thanks for the reply Louis... yeah I did use the one that came with the used tranny... the pump collar was good looking no signs of wear.

And the TC lockup worked great... believe me! when an aerostar (3.0, anyway) goes into/out of lockup, you know it. Seems to be a really high stall speed on those models.

Reply to
Backyard Mechanic

i've got one that comes mighty close to what you're saying about the weird tranny acting up.

we use to sell the early areostars and i drove one for many miles then, it started to leave oil spots on the back glass. traced it to the tranny, but it wasn't leaking ALL the time, just SOME of the time. i thought, "what?" never heard of this, so started to keep a mental log of when and where it leaked. we drove about 750 miles a week. found out as long as i did early upshifts and normal cruising speed, no leakage. but, when it would have to rev to a higher rpm, then i would get some spots. after the engine shifted, no problems and leakage would stop. drove about 3000 miles at least with this condition. the one eye opener came when i was passing a car and i ease down on the gas, but a condition presented itself and i had to go ahead and floor it. well, the tranny downshifted and the engine revved and the tail gate glass got covered in oil right away. i thought that i had blown the tranny. but i drove it easy to my business and checked the oil. it was down, but not critical.

we are only about 7 miles from the jasper engine factory and i had a master transmission rebuilder tear the tranny down and see what it was. he said the pump pressure was too high and that was causing the oil to go pass the seals. the when the pump slowed down, the seals would hold. he did replace the pump assy and do a rebuild. i'm sure that is not what you want to hear, but as i said at the beginning - i've got one that comes mighty close to what you're saying about the weird tranny acting up.

hope this info helps....

~ curtis

knowledge is power - growing old is mandatory - growing wise is optional "Many more men die with prostate cancer than of it. Growing old is invariably fatal. Prostate cancer is only sometimes so."

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Reply to
c palmer

PALMER snipped-for-privacy@webtv.net (c palmer) wrote in news: snipped-for-privacy@storefull-3214.bay.webtv.net:

... well, the tranny downshifted and the engine

Ummm ....no... it only depresses me further!

That's what I was worried about... Obviously there would be a designed pressure bypass valve and it's not working right!

No way a seal should go from no leak or minor seep to 'pouring out' in 60 miles.

That's for waterpumps with their dishwasher type seals that only give up when the bearing comes apart! :(

Reply to
Backyard Mechanic

You MAY be able to pull the valve body from the trans and check the regulator valve for a stuck / gummed up position... Do you still have the old trans? If so, you might wanna see about tearing into THAT valve body first.

'Course, on newer Ford FWD trannies (like the AXOD(TV and E) and not-so-new stuff like the ATX/FLC, the valve bodies have their own seperate access panel.. not so sure about the A4LD

Unless, of course, the friggin' regulator valve is stuck, and overpressure blows the seals. The older C-series and AOD trannies had it right, on that score, they actually had a vent tube on the tailshaft housing, so if the trans was suffering from overpressure, it sometimes could save the seals by pumping out the fluid through the vent...not so sure if the A4LD has a VT or not, though...

-LMB

Reply to
Louis M. Brown

Louis M. Brown wrote

Thanks, Louis...yeah I still have the old one

think I will do that

Reply to
Backyard Mechanic

One more thing! If you do tear into a valve body, do so either on a tarp or on something that'll prevent small parts (like small steel balls) from rolling off. I don't know if the A4LD has checkballs in it or not, but better safe than cussing up a storm...

-LMB

Reply to
Louis M. Brown

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