4.10 to 4.56 or 4.88

[4WDKC]

Something was wrong with his truck, my stock 350 TBI/700r4/410s,315/70r17 doesnt hunt at 70 and its no rocket either.

 

[Isaac nickerson]

what about 37s with 4.10 gears on a k10 but with the sm465. Stock early 70s 350. Will that be a complete turd?

 

[77 K20]

https://www.offroaddesign.com/blog/...tires-what-gears-should-i-put-in-my-axle.html

Offroad design had an article about what gearing they used on a bunch of different trucks they have. Basic theme was you needed pretty low gears for trucks with an OD transmission.

On something without an OD they said:

Similar story on our current “Cheap Truck”, a ’74 K20 with a 350/SM465 and 37s. It came with 4.10s and they work OK for driving around, keep the rpms down on the highway and were cheap since they were there. We do have to start in 1st gear sometimes on hills which isn’t super convenient but it’s still fine.


So it might be ok for you as long as you aren't towing or going up a lot of passes. I have 4.10s but have a fairly high torque 383 and the smaller highways around where I live all have a speed limit of 65-70. I just drive 65 and it likes it.