Which rear axle to choose??

[Fairbanks40]

Hey guys and gals!
I just joined! Yay! Anyway, my vice is a 71 FJ40 with a calm 350, SM420, Toyota TC with some Marlin goodies and 37" tars.
That's a centered output case (obviously), and I'm sure that this topic has been beat to death, but, name one that hasn't...
It has an FJ60 front axle assy C&T'd and it's titties! However, I have a mini truck rear axle assy in it and it scares me.. It has good brakes and lots of ground clearance, but I read that the housing is weak..? The places where I wheel, if it breaks in a bad way, the rig might be permanently "donated" to the land..
What do you guys think? Should I truss the housing up and upgrade the axles in the mini rear? I heard recently that a FJ80 rear axle will get the pumpkin close enough to center to work out? WWJD???
I don't do any hardcore rock crawling and I try to take it easy on my rig, but doesn't it always start out that way?

 

[Josie'sLandCruiser]

Hi all,

I'd suggest doing some online searching for upgrade parts for the mini-truck rearend. Definitely truss the axle housing.

Obviously, there are "better" (stronger) options for a rear axle - Dana 60, GM 14 Bolt, Ford 9 Inch, etc. These will take more work & cash to fit under the rig.

Good luck,

Alan

 

[White Stripe]

Do you have lockers? If not then just a truss and you will be fine. Otherwise a 100 series rear axle might be worth looking into. It might be too wide though compared to the front axle, I don't know how wide it is. It has a centered rear diff-I think its the 9.5" diff, and it has disc brakes, should be easy to find for a good price.

 

[Fairbanks40]

I looked pretty heavily into doing a 14 bolt, but I think it's just more than I need. Also, I don't want to go with tires bigger than 37's, so the ground clearance would be about that of a Camaro (sorry for the dirty language there)..
I'd really just love to find out that I can beef-up the mini rear for a few hundred and have some peace of mind..
I have a Lockrite in the rear. I have not looked into a 100 axle at all! Parts can be little scarce in my neck of the woods.. I'll check it out though. Thanks fellas!

 

[White Stripe]

Unfortunately, with a locker and a 350, the mini will not last even with mods. Do you have a traction bar? That will help. A 14 bolt will be much wider and heavier. A ford 9" would be a better choice if you want to go domestic, parts are cheap and tons of options and not too heavy. Check salvage yards, they often deliver for fairly cheap.

 

[Fairbanks40]

Yeah, I have some experience with the Ford 9" (like trying [and failing] to break one with a built 390 and slicks). The problem is I'd have to have custom axles made to have matching lug patterns, plus if I can't find one from just the right car, I'd have to narrow it (which if I have to run custom axles anyway, I might as well).
Is there such a thing as a third mortgage? Is that a thing?

 

[White Stripe]

Well i think the 9" will be cheapest. Having the axles drilled for bolt pattern should be cheap. But your location will make sourcing used parts tough no matter what option u choose. Or u could do a fj60 rear and put a Toyota split case from a fj60 in also. I wouldn't trust the mini-especially in Alaska with a v8. Unfortunately your gonna have to shell out some cash, but sell your leftover parts when your done to recoup some

 

[just differentials]

That mini truck axle won't hold up to that much power for long, you could always carry a spare third and shafts though. A truss, traction bars, and upgraded shafts will help though.

 

[pb4ugo]

Do you know what year your rearend is? You can find a l/c rearend and center the pumpkin. You already have 1/2 the parts. Pre 85 rear find a 40 or 55 rear. Post 85 I think you can use a fj60 rear. Look in. FAQ and search too, for hybrid mini/fj40 centered rearend. I did it w/ a pre 85 rear. No custom axles required. i heard you can do the same w/later model rears.

 

[Fairbanks40]

Took a while, but I finally decided on a rear end..
FJ80 with FZJ 3rd with elocker. Shortened the long side to center it.
Still have to finish. It's literally burning a hole in my hands right now..