I've got a friend that has built a mud bog truck, 1979 f250 with a 460, 5:13 gears with 44" tires. He said the truck will only go about a 100yds. in 4x4 before it will destroy the manual hubs. Is it possible it doesn't have reverse cut ring and pinion gears in the front differential? What do you think?

 

Sounds like he has different gear ratios in the two axles.

 

He claims it has 5:13's in both ends.

 

I would double check those ratios.

But how exactly the hubs get destroyed?

 

Does everything spin freely in 2x4?

 

He told me when you take the cap off the hub, he can see broken pieces. They put a third set off hubs on tonight and broke those. He called me later and said his father in law picked it up on the roll back and was taking it to the shop to find out whats going on. I'll let you know what they find.

 

What front axle is he running? if its a D44 thats his problem. he needs to be running a D60 at least with that large of tire on there. also what brand hub is he running?

 

He told me he had 3/4 ton axles in the front and back. Today he showed me a picture of the truck when I seen 5 lug nuts on the front wheel, I told him he only has a 1/2 ton axle in the front. With the tires he's running he needs a D60. He called the shop and confirmed that it does have a D44 in the front.
He's using Warn hubs I don't know which ones.

 

the d44 doesnt mean its 3/4ton. the d44 came in both 1/2 and 3/4 ton options but of course would be 8 lug if it was 3/4ton.

he for sure needs to be running a d60 in front and d6o or 14bolt out back. also should be running the warn premiums. they have a lifetime warranty ,free replacment if he was running the proper axles in the first place.