regearing and tranny work?

[StrokerAce74]

So im looking to regear for 37" tires. First off what gear should i jump to, stock is 3.73, and is there any tranny work that would have to be done?
thanx for the input

[peteoreo]

I would go with 4.30 gears with your 37s

[tbsimmons]

When I had my 04 6.0 I had 35's. I put 4.56's in it, I used that truck mostly for towing like this one was the reason.
The 6.4 likes a lower RPM so I would go with 4.30's if you dont tow, or not often, 4.56's if you tow a lot and dont drive over 70. Like everyone I have an opinion.

[cartmanea]

4.30s with 37s will be the same end ratio as 3.73s with stock tires, that would be a good fit.

[HotRodDiesel]

I've got 37's and I went with 4.10 My truck came geared with 3.31 and moved pretty good with those. My rpms are at like 1900 at 70mph. Decent milaege and good power. My .02