I went in to have my tranny fluid/filter replaced and when giving me the pricing for the job, they said that I could have any one of three transmissions.

How do I find out which one I have?
I have a '98 F150 4.2L w/OD.

Also they said that they would not put MERCON V in it.
Why not?
The end of the dip stick clearly calls out MERCON V.

They gave me some mumbo jumbo explanation that I still don't understand, then tried to get me to put in AMSOIL.

 

If you have a 1998 4.2L with an automatic, the only transmission possible is the 4R70W. The only other A/T Ford made for the F-150 in 1998 was the 4R100 and that has never been applied to the 4.2L engine. On the driver's side door jam, the Vehicle Cert. Label will note "TR". Below this will be the code "U" signifying the 4R70W transmission.

Also: If the dipstick says Mercon V that is what you need. Ford switched from Mercon to Mercon V for the 4R70W in 1998.

I also think they are simply trying to push the Amsoil on you. If you want Amsoil, it will work fine with your transmission and if you tow, it will guard better than most. But it will cost twice what the MotorCraft Mercon V will and you need at least 14 qts.

Only use a fluid that meets Mercon V specs in your trasnmission. This is what it requires.

 

AjRagno... How can I tell if I have the E40D or the 4R100? My VIN says E40D but the harness connector matches the 4R100 and is different from the E40D. I have a 1997 Expy with the 5.4 and tow pkg. Dealer says that even though the VIN shows it to be an E40D that it still could be the 4R100 because 97 was a transition year.

 

davet,

The 4R100 is an E4OD. There may be some slight differences between a 1997 and a 1998 build transmisson. There are also internal differences between models for added strength. But unless you're rebuilding it, there's is nothing to grow concerned about.

Unlike the 4R70W, the E4OD/4R100 requires regular Mercon fluid; I think 16 qts. No Mercon V for this transmission.

 

Thanks.