My current rig has DANA30 front, DANA44 rear, 3.73 ratio, limited rear slip differential, stock 30 inch tire. Nothing exciting and pure stock performance.
I am planning to upgrade it to fit in 35 inch tire. To me, all upgrade should
start from a healthy internal meachnism.
Therefore, I think before resizing the tire, a upgrade in the gear ratio
is needed so that the effective gear ratio will be near stock for on street
driving and really low for good trail performance.
Now I am facing two choices, upgrade axle gear ratio or upgrade transfer case.
My research so far so showed the pro/cons on each choice as
Axle Gear Ratio Upgrade:
Pro: Parts price is affordable, 400 dollars can get both front and rear
pinion/ring pairs.
A lot of ratios can be selected ranging from 4.1 to 5.38.
Can be done with locker upgrade at the same time.
Con:
Expensive labor.
DIY is hard, not only because you have to deal with a lot of stuff
before reaching the pinion and ring part, but also the adjustment of
backlash and preload is quite tricky and time consuming.
have to do it on both front and rear axle
When upgrading the gear ratio, if we do not upgrade axle
(from DANA30 to DAN44 or from DANA44 to DAN60)
it will make the axle weaker.
This is because lower gear ratio require smaller
pinion size or larger number of ring gear teeth, making
contact area between pinion teeth and ring teeth smaller than
stock size.
Transfre Case Upgrade:
Pro: Just need to change one part (transfer case) then two (two axles)
Atlas-4speed unit provide a wide choices of gear ratio. Compared
to it, stock transfer case provide only two choices, the one for street
use is too low and one for trail is too high.
keep the stock axle strenght without weakening it
Cons: Expensive Part, expensive labor
Do not know if it is suitable for DIY, since it seems like a
really big change and you have to at least cut center console
to let the new stick of the transfer case to through
All above is my current research result and there maybe some erros.
corrections/comments/suggestions?
