75gmck25
Full Access Member
- Joined
- Oct 13, 2016
- Posts
- 2,304
- Reaction score
- 2,273
- Location
- Northern Virginia
- First Name
- Bruce
- Truck Year
- 1975
- Truck Model
- K25 Camper Special TH350 NP203
- Engine Size
- 5.7
Stock gearing for a K20 should be 4.10. Are you sure the transfer case is really in High? Shifter alignment can be way off, so maybe it’s actually in low range. 4.56 was also an option, but I think it was used mostly in the K30s.
TH350 was stock in many of these trucks and it will hold up fine for most uses. Just get a good stacked plate trans cooler. However, many do choose to swap in a TH400 op if they are off-roading.
TH350 was stock in many of these trucks and it will hold up fine for most uses. Just get a good stacked plate trans cooler. However, many do choose to swap in a TH400 op if they are off-roading.
