I regeared my
Dana 20 TCase with the TerraLow kit and I love it. Stock gearing is 2 to one for 4WD Low. I think that's far too much of an overlap.
The TerraLow kit puts the gearing at 3 to 1.
Here's my gearing:
................1st........ 2nd..... 3rd .....4th
T-18A ....
6.32 . . . . 3.09 . . .1.69 .....1
4WD Low . 12.6 . . ..
6.18 . . .
3.4 ..... 2
TerraLow . 18 . . . . . . 9 . . . .
5 . . . . . 3
You can see with the stock
Dana 20 if I am in 4WD low the only time I get lower gearing is when I am in first.
In other words if I have a stock
Dana 20 in 4WD Low then 2nd is the same as 1st with the TCase in high.
3rd in Low is the same as 2nd in high.
See what I'm saying? There is too much overlap.
Yes my
T-18 has a wider range than most trannys.
IMO the best TCase would have a 4 to 1 low. There would still be a little overlap even without a wide ratio
T-18 Tranny.
My TerraLow kit cost $850 and it was well worth it. The kit replaced every gear in the TCase so it was also an excellent rebuild kit. It was actually very easy to do.
Edit: I don't know anything about using parts from a Jeep Dana 18 and 20 along with a bronco 20.