Transfer case question


Sharpest Tool
Jun 15, 2010
Willys Model
Willys Year:
Well I ordered the rebuild kits for my transmission and transfer and guess I didn't know that there is three different kits for the transfer. Got an email from the guy asking me which one I need. What shaft do i need to measure so I know if it is 3/4 1 1/8 or 1 3/4?
Hey Jeff,
you'll need to measure the intermediate shaft. It's the one that you can see from the back side of the Xfer case body. You'll see a lock tab there to hold it in.

In stock configuration, the 4cyl models should have been 1 1/8"
The 6cyl models - 1 1/4"

Remove that tab to get an accurate measurement. DON'T FORGET TO PUT IT BACK ON. :) :cheers:
When building my truck, I went with a T-18 transmission out of J-10 Jeep truck. It had a Dana 20 transfercase, the main difference is the size of the hole that is towards the transmission. Large hole 20 small hole 18, anyway I had the gears and outputs from my Dana 18 put in the the Dana 20, giving you the larger intermediate shaft with lower gears. I was told by a friend who recommended this it is called a super 18. I will see if I can find any info on line.
Here is a link that tells you everything you ever wanted to know out the Dana 18... There is one paragraph about the "super 18".

"The "large case" version of the Dana 18 was the most improved version of all. It was only found behind the Buick V6 engine with its T86 and T14 transmissions. The case casting used was that from the Dana 18's progenitor, the Dana Spicer Model 20. This case featured a 4" locating bore and a single stick shifter and new front output cap. The front output assembly did not provision for a shifter mounting point, as the shifter was anchored to a transmission bracket. The internals were essentially identical with the standard Dana 18. This version is best thought of as Dana 18 guts in a Dana 20 shell. Individuals can build a "Super 18" by copying this version."

In my case, I kept the twin sticks and offset output from the Dana 18, they transfer over to the Dana 20.