Lug nut torque

Airstreamer67 wrote:
They're driving BIG rigs. Compare them to the F350. It's all proportional.

NOT! 2003 Newmar MADP 400hp. turbo diesel on a Spartan Mountain Master Chassis with Michelin 295/80R 22.5" tires on Alcoa aluminium wheels torqued to 450-500 foot pounds of torque! I hope this explains it. The F350 is a "matchbox toy" compared to that. :)

I thought that was my message too. It's all proportional.

A 9000 pound truck with 140 ft-pound lug nuts vs a 35000 pound coach with 500 ft-pound lug nuts.

Sounds proportional to me. No?

Geocritter wrote:
I have to ask, what are you guys drivin'? 450-500 ft. lbs. is bolt snapping range for most of what I work on. I freaked when I first read this thread and I went and looked at the Ford Chassis manual that came with the 1994 33' Holiday Rambler I bought recently. The manual (for Ford Super Duty trucks) gave 140 ft. lbs. which is more in the range I expected.
Steve

Geocritter,
A simple explanation is that the larger, mostly diesel pusher rigs use the larger 22.5" tires and wheels and, pretty large lug nuts and studs. (Our lug nuts are 33mm and a the stud is around 3/4" in diameter). While the somewhat "smaller" chassis'd units use the 19.5" tires and wheels and therefore, smaller lug nuts and studs. And then there's the units like the general Class C units that at least used to use, 16" wheels and tires. Some may still do, no idea.

Obviously, the larger the lug nut/tire wheel combo, the higher the torque for holding things on and together. As stated earlier, our lug nuts have stamped right on the outer edge, "450 ft. lbs." Hope this helps some.
Scott

True about lug nut size vs. ft-lbs, and another tip off is the number of lug nuts for the wheel. The more lug nuts, the less the ft-lbs can be.

My 19.5 wheels have 8-7/8" studs and the Workhorse manual states that the lug nut torque is 475 ft.lbs.

My 19.5 wheels have 6-1&1/8" lug nuts. Torque is 475 ft-lbs.

F-53 MH chassis manual states 140 ft pds lug nut torque. There was an update later increasing it to 165. This is on a F500 size truck chassis. I belive the OP was asking about a different chassis altogether. Please make sure you (and your tire or service guy)know YOUR particular lug nut torque before installation.

Airstreamer67 wrote:
I thought that was my message too. It's all proportional.

A 9000 pound truck with 140 ft-pound lug nuts vs a 35000 pound coach with 500 ft-pound lug nuts.

Sounds proportional to me. No?

You are correct sir!