What rear axle do you have? If it is the 8.25, then you are ok for 35" tires. If anything, order a set of Dutchman alloy shafts and keep your stockers as spares. The nice thing about the 8.25 is that the axle shafts are identical side to side, so you don't need a separate spare for each side, and instead will have two spares. Pulling the stock shafts to replace with alloys will teach you what you need to know for trail breakage. 29 spline alloy shafts are enough for 35's unless you really get on it.
For the front...people wheel the Dana 30 with 35's all the time. You have 297-x u-joints, which is the same as a 44. The bigger problem is ball joints don't tend to last and the housing doesn't have as much rigidity as you'd like for 35" tires, plus you have that little caster vs. pinion angle problem on tall lifts if you spend a lot of time on the road (a set of Warn hubs in 5 on 4.5 pattern takes care of this).
But these issues don't tend to be deal breakers for people who don't like to spend a lot of coin unless you are running the really hardcore stuff. You could buy a set of Warn shafts if you really wanted to...or just carry a set of spares. Learn how to take off the hub and put in a new shaft assembly before you are out on the trail.
I'll give you some advice: don't overthink this thing. I know how to pull a hub and change an axle assembly, and how to change rear axles...but I still bought a Currie high pinion 9" as well as a complete front HP Ford 44. There was ultimately very little to be gained in trying source the parts and do it myself. This is because I run stock width axles and 3.75" backspace rims for more track width (with 34x12.5 tires). Once you are cutting down an axle and rotating the tubes you are having a shop do the work for you. Unless you can install your own gears, you'd might as well let them put in the differential, gears, and shafts unless you have an axle where you are reusing stock parts.
Look at it this way: a custom built Ford 9" housing from Currie is only $200 - $300 (the HP third member is a bit of coin, though). You are going to want a locker, gears, alloy axle shafts and disc brakes whether you use that D60 housing or start with a custom housing. Ford 9" parts tend to be the cheapest around. If you really want to learn, consider buying a custom spec'd Currie housing and high pinion 3rd member, and learn to do the differential, gears, and axles yourself...you can source them through whomever you want and Currie can provide the axle specs...and then you can take all the time you want.
For the front, have a shop cut down the Ford 44 and rotate the pinion to suit your lift, plus weld on mounting brackets (ask a lot of questions on this board before you decide what suspension to run so you don't spend a lot of money on less than perfect brackets) and then do everything else yourself now that you know how to set up a diff.
But as long as you have an 8.25 rear, you shouldn't worry too much offroad, just don't do anything stupid.
Nay
