D20 transfer case swap

[70truck]

I'm wanting to get rid of the single speed transfer case I have(D21). I have the NP435 trans and I've been researching and have read that the only "direct bolt-in swap" for the D21 is the D20 due to the spline count. I read that they came in early broncos and that the drive shafts would have to be modified. So I have a few questions.

1. What yrs exactly would the "early" broncos have the D20?

2. When looking at the tags, what would ID the D20?

3. How would the drive shafts have to be modified? (shorten,lengthened,etc.)

Thanks guys!!

 

[braxton357]

66 through 77 would have a d20. pre 72 having the lower gear ratio but also being T shift. I don't know anything about dana 21's, but I assume this is a ford and not a heep? The eb 20's have a different bolt pattern than the jeep and scouts. You can find them for $100-150 all the time.

 

[70truck]

Thanks, do you know what the difference in the ratio's are?

 

[RHSCTJ]

Not much. 2.34 to 2.46.
http://www.high-impact.net/transmission_and_gear/Tcase_Dana20EarlyBronco.htm

 

[roll-a-jeep]

d2o swap

call john at border parts in santee california. 1-800-533-0171. this man knows all and is a drivetrain parts vendor since 1950's.

 

[70truck]

Not much. 2.34 to 2.46.
http://www.high-impact.net/transmission_and_gear/Tcase_Dana20EarlyBronco.htm

Great link! Thanks!

call john at border parts in santee california. 1-800-533-0171. this man knows all and is a drivetrain parts vendor since 1950's.

Thanks!