Tires and Axles (reference)

[Swampy]

I am not sure where a thread like this would go. I just wanted to compile a basic understanding of what tires to run on what axles (d30, d44, d50/60, 8.8, 8.25 etc)

 

I know people draw the line at 35s on a d30, 37s on a d44 and 37+ for 1 tons. But what are the actual limits of these axles to the best of our abilities. I know driving style, intended use and terrain affect numbers. As do sleeves, truss kits, chromo axles, carriers and the like. 

 

But from experience wise say, on a d30/8.25 combo how big can you go? Some people say its just as strong as a d44 because u-joints are the same size. I know of a fellow with an xj (d30/8.25 combo) on 40" tsl's here in Florida. I know @12valve.tj knows him and his youtube channel has videos of his setup. Mind you most of the time its on the street or on swampy/muddy trails, but he is still making it work so whats the limit?

 

 

[Swampy]

His explanation....

 

 

[88whitemanche]

Buddy of mine has 38s ground hawgs on his xj 

4.0 nv3550 

dana 30 open carrier 4.10s

29 spline 8.25 powertrax no slip locker and 4.10s

and he hasn’t broken a shaft yet... but he does carry spares just in case....

well he doesn’t rock crawl but he does mud a lot and beats on it when he wants to and it’s his daily

[Pete M]

there are a LOT of variables in play here.  terrain, driving style, tread pattern, locked/open, truss, etc.  A dana 30 is way tougher than its name implies, but it has limits.  personally I wouldn't go bigger than some 33" mud terrains, but I'm a cautious person since I usually need to drive the truck home.   I put a 44 in the front of my truck because I wanted more of a project than just a bolt-in 4wd conversion. 

 

and for every guy that runs giant tires on a dana 30 and doesn't have any problems, there's a guy like me.. who cracked a ford 9" case in half (we think by dropping it on a rock), so nothing is invincible.  

[Swampy]

I was going to mention that cherokee too Walt. 

And Pete there are plenty of variables, and I'm sure there is a guy out there that if you give him anything he will brake it. But beyond the scope of just a d30 all axles of sorts. I guess it depends on what driving you are going to do as a pavement princess has different requirements than a rock crawler/mud/ trail rip or even a DD

[Swampy]

I am not sure what my end goal is either 35s, 37s or 40s. Probably going to stay at 35s as it'll be a comfortable/reliable spot on a well built d30. Work with what you got right?

 

Decisions Decisions 

 

But just as a reference

Front axle:

HP D30- 

LP D30-

HP D44-

LP D44-

D50/60-

Unimog axles-

2.5T Rockwells- 

 

Rear axle:

Ford 8.8-

Chy 8.25-

Chy 8.75-

Sterling 10.5-

D70-

Ford 9-

D44-

14bolt-

D35-

Amc20-

Chevy 12 bolt-

 

Aftermarket crate axles?

ProRock 44-

Prorock 60-

G2 44-

Currier?

[Pete M]

don't for get to consider how much driving it'll see and the local rules about lifts and tire coverage.  

[Swampy]

@saveevryjp1998 i was thinking the same thing about a 44, but id rather build something I already have to handle what I need it to. The only down side to a d30 is that you can only go down to 5.13 gears and not 5.38 like a d44. With that 2.5l and 5.13s, 35s are as big as I would want to go to still be able to drive on the highway. But if I rebuild the motor for more power I maybe able to go to 37s

[Swampy]

7 hours ago, saveevryjp1998 said:

I thought about that with my 86 2.5 if I were to lift it. My thoughts are I'm wasting my time with an offroad 2.5. I like it for the street and think there is plenty there and efficient as it was designed for, but as a lifted offroad truck with 37's is not realistic. Mine 2.5 will not ever have anything other than fresh stock setup to make a superb clean cool little 30 plus year old truck with great economy.

I totally understand this but as someone who wanted a solid axle 4x4 truck has always been a goal of mine. Even to the point I thought about doing a solid axle swap on my 2wd ranger. But I'm glad I was able to scoop up my mj, and build it/wheel it. 35s will be my reasonable limit

[Swampy]

 Yes building it as a jack-of-all-trades is my goal. Not really good in one area, but can handle a little of everything tyoe of trail rig