OK, this shouldn't be this hard. I have a 99 4.2 F150 and an 88 4.9 F150, both the M5OD trans. I believe it is what they call the Mazda trans with the concentric slave.

The rear tranny seal on the 88 is leaking. I was planning to have the trans out of the 99, so figured I would get a new seal. Ordered by application from Rock Auto. Everything else I got was correct.

They sent two little bitty seals, OD of 1.978 and ID of 1.26. Way too small.
Figured it was just a snafu. So, I go by O'Reilly's and try to order the rear seal. The store I was at is out, but the one two blocks from where my angel of a wife is sitting has it. So I call her and she goes by to get it.

Same little bitty seal that Rock Auto gave me. I believe the one I need is 2.371 OD and 1.496 ID.

Is there some misinformation out there that results in the same mistake from two vendors?

Can anyone give me a part number?

 

Rear main seal for the engine, right? I'd go see if the Ford dealer has any and look at them.

 

Sorry. I was unclear.

Need the rear tranny seal. The 4.9 has a new rear seal, and the 4.2 is a brand new engine.