Drive Axle with Aluminum on the out side Steel on the inside.

johns4104s · July 29, 2009, 08:07:16 PM

I just got of the phone with a experience trucker, he brought up the fact that there very well could be problems with studs shearing with the dissimilar metals, Aluminum on the out side and steel on the inside. Any thoughts from you guys?

Thanks

John

TomC · July 29, 2009, 08:16:43 PM

Most bus axle housings are all cast iron. Aluminum housings are typically used only on trucks for weight savings. So your experienced trucker is correct-but just for truck axles. I believe you'll see once underneath that your axle is all cast iron. Good Luck, TomC

luvrbus · July 29, 2009, 08:24:54 PM

Tom, John is talking about the wheels I think right.
John I have bought new trucks from Peterbuilt that came with steel wheels on the inside and aluminum on the outside and never had that problem.

good luck

Dreamscape · July 30, 2009, 01:05:42 AM

John, A lot of guys run that way, besides it would take a bunch of years for anything to go wrong. The shearing was caused by metal fatigue of many years of abuse and over torquing.

Paul

gumpy · July 30, 2009, 06:20:55 AM

Quote from: Dreamscape on July 30, 2009, 01:05:42 AM
John, A lot of guys run that way, besides it would take a bunch of years for anything to go wrong. The shearing was caused by metal fatigue of many years of abuse and over torquing.

Paul

Or loose nuts.

DaveG · July 30, 2009, 07:17:52 AM

Should be no problem with alum outers and steel inners, just use the correct inner nuts, they are longer on the treaded part for the alum wheels and do not have a boss area that goes into the inner wheel, just the taper for centering. Dis-similar metals is not gonna be an issue here.

You are correct, trucking has been doing this for a long, long time, and it is not related to steel or alum hubs.

If you need part numbers for the inner nuts, let me know and I'll get them for you.

RJ · July 30, 2009, 08:17:16 AM

Quote from: gumpy on July 30, 2009, 06:20:55 AM

Or loose nuts.

Hey, that describes a lot of us here!!

kyle4501 · July 30, 2009, 09:11:19 AM

If Alum wheel is sufficiently over-torqued, the tapered nut seat will distort. Usually this distortion effectively reduces the thickness which leads to difficulty in keeping the nuts tight - which leads to more over-tightening which leads to . . . . .

If you're having problems with lug nuts & studs, the cause could be:
1- damaged hardware (from overtorque or even stud installation abuse)
2- bad/ cheap or otherwise incorrect hardware (studs or nuts)
3- damaged nut seat in rim
4- wrong brake drum?
5- wrong wheel

I hope youe wheel issues are behind you & smooth travels lie ahead.

Sean · July 30, 2009, 09:47:42 AM

Alcoa sells a dielectric spacer that should be used between steel and aluminum wheels to prevent damage from electrolysis. I use them between my duals; many folks also prefer to use them between the steel brake drum and the aluminum wheel on singles.

Many of us with hub-piloted wheels have no choice but to run steel inners, because the pilot lands are often not long enough to engage dualed aluminum wheels (mine are not).

-Sean
http://ourodyssey.blogspot.com