Which one of these transmissions are the best one? I was under my truck and noticed I had the 5X which I think someone told me was a little better than the 4X. Whats the diffrence?

 

ttt

 

No such animal as the 4X. The 99s got the 1F, 2000 got the 1S, early 2001 got the 1J (which is the one you want to avoid) and the late 2001 up got the 5X. Of the bunch, the 5X is the best. The differences are very minor except the 1J which has the mechanical diode. The 1F has the green solenoid, which has a less restrictive filter and is completely interchangeable with the orange one the rest have. The 1F also has the old style intermediate brake drum (the direct drum) that has the bronze bushing, after 1999 Ford eleiminated that part. The 1S and the 5X are identical, except the friction material on the intermediates is different.

Hope this helps,

G

 

Thank you! So I do have the "good one"

 

What is the "old style" intermediate brake drum? Why did they do away with it?
Do all '99's have this or the early ones? My '99 is one of the last ones built.