Is it a pretty good bet that the 4 speed in an 86 F250 diesel is a T18?

Originally posted by Dirtpan
Is it a pretty good bet that the 4 speed in an 86 F250 diesel is a T18?

No

I'm not 100% but I think T-18's were used just through 85. Can you post a pic or give a description?

I just searched over at The Diesel Stop and it would appear that the T-19 would be the diesel tranny for 1986.

The 83-86 Diesel and 460 trucks got T19's, and T19's only....
The diesel version has the 4.02:1 first gear close ratio gearset, in both 4x2 and 4x4 versions, the 460 trucks got the 4.02:1 one in 2wd, but, 4x4's got the same ratios as a T18-A, with a 6.32:1 first gear(Mine positively kicks ass)

I just bought a T19 out of an 84 F250 diesel, and it has the 5.11 gearset. I had heard this ratio was used in 83-84, but wasn't sure until I found this one.
Rick

Duh... Now that I think of it, I've seen an 86 diesel with the 5.11 gearset.
My buddy has an 85 6.9/T19 in his 88 F350, it's definatley the 4.02:1 box, dang near stalls the 6.9 taking off, and he's got 4.10's with 33's...