All,
The van had sat 7 years prior to my purchase.

Worked out the performance issues (Fuel issues) and I am now at the transmission issue.

I was told by the last owner, long time family friend (knew the guy 35 years)that became disabled and is now deceased, that transmission was replaced prior to him parking the vehicle. I know nothing more about why or if it was working properly after or not. I know the vehicle stopped being used as he became wheel chair bound and his health continued to worsen.

Anyways, the automatic transmission appears to shift 1 thru 4 and reverse fine. The transmission will pop out of 4th gear and "free wheel". Does not appear to grab funning or attempt to grab 4th until you let up on the gas and let the MPH drop considerably and you press the gas to speed up which I believe it picks up third and then drops back in fourth.

There is no burnt smell in the transmission and fluid is clean.

I am wondering if its something simple;
1) Wrong fluid?
2) Clogged filter (not dirty so I doubt)
3) Misaligned shift mechanism
4) Sticking valve in valve body

Or something a little more complex
1) Bad Band
2) Broken Seal
3) Bad Clutch/Plates

I think the first step is identifying the transmission (Model). Does anyone know the transmission that would be in this vehicle? I have quite a few ATSG manuals and I may have it sitting. I have had my fair share of Ford Vans/trucks.

The fluid type, I believe its Mercon III...Confirmation?

Any ideas?

Thanks,
Chris

 

No, it isn't MERCON III. There is no such fluid as MERCON III and never has been. When it was built the correct fluid was MERCON. MERCON V has now replaced MERCON for all applications.

There should be a data tag in the driver's door opening. On the tag will be a TR with a letter underneath. This letter identifies the transmission. Alternatively I often can tell what transmission it has if I know what engine it has.

 

It has a 5.0 L.
Thanks,
Chris

 

All,
Its actually a 1991 and the Trans letter is a T.

Thanks
Chris

 

All,
Need a confirmation but I believe its a AOD. (4 speed Auto)

I counted I believe 14 bolts...pretty much a rectangular pan....Is this a AOD?

TR number on the door says 'T'.

Thanks,
Chris

 

Yes, that's an AOD. I don't know a lot about AODs, but I do know they had a lot of problems with the overdrive band. That is my guess as to what your problem is.

 

Well I have some experience with this transmission.....Did this in my Auto Tech Transmissions course I took at the Community college. If I remember correctly there is no band adjustment for the band and there were problems with the pistons sticking and or seal issues in the piston for the band.

This along with the possibility that the band could be burned out is a good place to start. I believe the text book I have either went through it or I have the ATSG manual on it. Will have to dig it out of my garage.

Thanks,
Chris

 

All,
Found my ATSG Manuals and I do have a AOD manual.....

Anyone have any pointers or things to look for please let me know,,,,I have some reading in front of me...to refresh my memory.

Thanks everyone,
Chris