Tires and Gears

[4x4incountryboy]

I am building a 1990 regular cab Chevy stepside with a 6'' suspension lift and a 3'' body lift. I was wondering what the best looking tire size to lift size combination was aswell as the size tire spacer if needed. It has a 400 worked smallblock and a turbo 400 with 373 gearing. Will/ SHOULD I regear? Please help and give suggestions. (tires have to fit 17'' rim)

 

[ChrisAU]

You're going to want at least a 37" tire with a 6"+3" setup, so yes I'd say re-gearing is definitely needed. 4.88's would be optimal for a 37/38.

 

[4x4incountryboy]

when I regear would anything need to be done to the tranfercase like a swap or upgrade? With 37's would a tire spacer be needed?

 

[k_pro1992]

Id go 38.5s and 5.13. The spacer all depends on the width of the tire and the rims offset and backspacing

 

[4x4incountryboy]

And with 4.88s would that be an ok daily driver gearing? It isnt only a mud toy.

 

[am92]

And with 4.88s would that be an ok daily driver gearing? It isnt only a mud toy.

Depends on how much city vs highway driving you do, but 4.88 with 37's should be about the same as 3.73 with stock tires IIRC

 

[k_pro1992]

It all depends on what kinda driving you do the most of city or highway. Lower for city higher for highway

 

[4x4incountryboy]

will 4.88s in a 10 bolt kill the pinion gear under excessive load from tires and offroading?

 

[am92]

Yes. Probably sooner rather than later, but its not the gears, its the much heavier tires and the increased load being put on an already weaker than it should be rear end

 

[k_pro1992]

Eventually it will break but so will everything else. If you want a stronger diff get a 14 bolt sf but we have 5.13s in a playtoy with 39 super swampers and the 10 bolt has held up for 3 years.