Dave to answer you last question "The question is, does any of this apply to
the GMC?" the answer is absolutely and positively not! But than it is not
applicable to any other vehicle either. Torque specifications are not
interchangeable between dissimilar vehicles. And since you did not give the
size of the wheel studs there is no way of knowing if anhg of the
specifications are relevent. Engineers give torque specifications for each
wheel application and it is best to follow the guidelines for that
particular application.
The owners of GMC motorhomes on this net must be pretty confused by now with
all the advice they are receiving with regards to whether to oil or not oil
their wheel studs and nuts. What is the correct answer? Simple. Do exactly
what your owners manual tells you to do, nothing more, nothing less. All
stated torque values are considered to be on dry surfaces UNLESS OTHER WISE
NOTED. For GMC steel wheels thats 250 Ft lbs DRY. For Alcoas that is 140 ft
lbs DRY. If you oil the threads or nuts you will over stress the studs and
or gall the wheels if you still torque them to 250 ft lbs or 140 ft lbs
respectively. Will they fail? Who knows, but why take the chance?
>Netters,
>I have to put my 2 cents worth in also. We have been running aluminum hub
>piloted wheels on our big trucks for about 10 years now. It has been common
>practice to oil the studs but it can be over done. A rule of thumb - no oil
>should contact the wheel. The oil should be on the thread surface and a drop
>added between the washer and nut at the swivel. The problems with loose
>wheels usually occurs from not cleaning the mating surfaces thoroughly and/or
>under-torqued nuts (not cleaning and oiling the studs can result in
>under-torqueing even though the torque wrench was used correctly). This
>allows the wheel to rotate slightly about the hub under acceleration /
>braking due to inadequate clamping force of the nuts. This is what loosens
>them. It will also wear the pilot area turning the Alcoas into the shiniest
>piece of metal in the scrap aluminum bin. Anyone changing hub piloted wheels
>needs a torque wrench or a torque limiting impact that is calibrated on a
>fixture often. Just running the nuts down with a regular impact is not good
>enough. We have lost a wheel only once. It was on our first truck running hub
>piloted. A driver changed the tire on the road, who did not have the training
>or tools to torque it correctly. Later that afternoon it was seen heading off
>across a farmers field never to be found again. Since then we stopped
>carrying spares on the trucks and send out a service truck instead. Other
>than that, I can't think of any other problems with these wheels. Torque and
>clean is essential, much more so than stud piloted wheels.
>
>We also have to be concerned about corrosion due to dissimilar metals which
>is accelerated by road salt. It would take a long time for the corrosion to
>ruin the wheels due to the seemingly high quality of the alloy but there is
>the problem of the wheel seizing to the hub. This was a big problem for us
>before using anti-seize (made by permatex). We apply it to the wheel and hub
>pilot areas liberally and now use it on the studs instead of oil. We also
>install a plastic gasket called "Wheel Guard" between the wheel and brake
>drum.
>
>I have talked to an Alcoa engineer who said there is nothing wrong with our
>practice. He also stated that Alcoa does not recommend for or against the use
>of Wheel Guards. But starting next year Alcoa is going to start manufacturing
>them, if that tells us anything. I have not found a Wheel Guard yet to fit
>the 16" wheel but I am going to install them if I do. I'll also post it.
>
>That's how the big trucks do it in Michigan. 42 wheels per rig carrying
>154,000 lb. , 30 rigs in the fleet. The question is, does any of this apply
>to the GMC?
>
>Also, there have been some posts describing the air brake system on trucks
>that have not been totally accurate. If anyone needs to know how they work, I
>would be happy to answer an email since I don't see how it can relate to the
>GMC.
>
>Dave Meekhof
>73 Glacier 230.
>
>
the GMC?" the answer is absolutely and positively not! But than it is not
applicable to any other vehicle either. Torque specifications are not
interchangeable between dissimilar vehicles. And since you did not give the
size of the wheel studs there is no way of knowing if anhg of the
specifications are relevent. Engineers give torque specifications for each
wheel application and it is best to follow the guidelines for that
particular application.
The owners of GMC motorhomes on this net must be pretty confused by now with
all the advice they are receiving with regards to whether to oil or not oil
their wheel studs and nuts. What is the correct answer? Simple. Do exactly
what your owners manual tells you to do, nothing more, nothing less. All
stated torque values are considered to be on dry surfaces UNLESS OTHER WISE
NOTED. For GMC steel wheels thats 250 Ft lbs DRY. For Alcoas that is 140 ft
lbs DRY. If you oil the threads or nuts you will over stress the studs and
or gall the wheels if you still torque them to 250 ft lbs or 140 ft lbs
respectively. Will they fail? Who knows, but why take the chance?
>Netters,
>I have to put my 2 cents worth in also. We have been running aluminum hub
>piloted wheels on our big trucks for about 10 years now. It has been common
>practice to oil the studs but it can be over done. A rule of thumb - no oil
>should contact the wheel. The oil should be on the thread surface and a drop
>added between the washer and nut at the swivel. The problems with loose
>wheels usually occurs from not cleaning the mating surfaces thoroughly and/or
>under-torqued nuts (not cleaning and oiling the studs can result in
>under-torqueing even though the torque wrench was used correctly). This
>allows the wheel to rotate slightly about the hub under acceleration /
>braking due to inadequate clamping force of the nuts. This is what loosens
>them. It will also wear the pilot area turning the Alcoas into the shiniest
>piece of metal in the scrap aluminum bin. Anyone changing hub piloted wheels
>needs a torque wrench or a torque limiting impact that is calibrated on a
>fixture often. Just running the nuts down with a regular impact is not good
>enough. We have lost a wheel only once. It was on our first truck running hub
>piloted. A driver changed the tire on the road, who did not have the training
>or tools to torque it correctly. Later that afternoon it was seen heading off
>across a farmers field never to be found again. Since then we stopped
>carrying spares on the trucks and send out a service truck instead. Other
>than that, I can't think of any other problems with these wheels. Torque and
>clean is essential, much more so than stud piloted wheels.
>
>We also have to be concerned about corrosion due to dissimilar metals which
>is accelerated by road salt. It would take a long time for the corrosion to
>ruin the wheels due to the seemingly high quality of the alloy but there is
>the problem of the wheel seizing to the hub. This was a big problem for us
>before using anti-seize (made by permatex). We apply it to the wheel and hub
>pilot areas liberally and now use it on the studs instead of oil. We also
>install a plastic gasket called "Wheel Guard" between the wheel and brake
>drum.
>
>I have talked to an Alcoa engineer who said there is nothing wrong with our
>practice. He also stated that Alcoa does not recommend for or against the use
>of Wheel Guards. But starting next year Alcoa is going to start manufacturing
>them, if that tells us anything. I have not found a Wheel Guard yet to fit
>the 16" wheel but I am going to install them if I do. I'll also post it.
>
>That's how the big trucks do it in Michigan. 42 wheels per rig carrying
>154,000 lb. , 30 rigs in the fleet. The question is, does any of this apply
>to the GMC?
>
>Also, there have been some posts describing the air brake system on trucks
>that have not been totally accurate. If anyone needs to know how they work, I
>would be happy to answer an email since I don't see how it can relate to the
>GMC.
>
>Dave Meekhof
>73 Glacier 230.
>
>
