Drivetrain decision

[VtPeter]

I am in the process of building a Fhead powered 3b for long distance adventures. Most of the time I'll be on back dirt roads and mild trails. I don't need to go much faster than 50mph. I'd like to end up with a very dependable and quiet running drivetrain. I have a lot of parts available to choose from. T90a, T90c, D18, Dana 20 , D27/30, Dana 44 's both offset and centered. I do not have an Overdrive . Tire height 29-30".

My first thought would be to use a T90a/Dana 20 with a centered Dana 44 . If I used a 4.88 axle ratio, that would give me a little more speed than the 5.38's. Does this make any sense ?

Or, should I go with a T90c/D18 with 5.38's and buy an Overdrive ? This would be a more complicated system, but would probably perform better in some situations.

Your thoughts would be greatly appreciated

 

[JeeperChris]

It sounds like the T90c/D18 with Overdrive would give a little better low gearing for the slower stuff and still give a good top end. I would choose that if it were mine.

 

[Patrick]

The stock configuration should suffice given your intended purpose. The only problem might be the crappy steering design of very old CJ’s.

 

[VtPeter]

I will be using a completely rebuilt V6 Ross steering box, 2 hole knuckle upgrade on the D27. Everything else is in excellent condition. With that being said, I have a new non power Saginaw box and all the linkage to swap in if my original plan is not satisfactory. If this Jeep was intended for more difficult trails, or using larger tires, the original Ross system would definitely be a weak link , even in good working condition.

 

[Patrick]

Right on.