ramenth
Well-Known Member
Hey, folks, just figured I'd post this up to take some of the mystery out of the aluminum wheel re-torque issue.
We've all seen it: take your car to a tire shop and walk out with a receipt that has a disclaimer on it saying that you should re-torque your aluminum wheels after so many miles or you've been talking to a buddy about how we has driving along one night to have one of his tires pass 'em because the the wheel came off.
I worked for a guy one time who worked on a lot of high end imports: BMW, Benz, Porsche, even once worked on a Ferrari and he was pretty anal retentive about following the TIA's (Tire Industry of America) recommended guidelines for proper wheel torque. Later on, when I went to work for a local tire/suspension/alignment shop I had to actually take these training courses, both for pass car and heavy duty trucks.
The other day I had an '04 Jag sitting in the shop, checking the tires over for leaks and doing a rotation when I decided to take some pics and offer up some of my knowledge and experience on aluminum wheels and the proper torque procedures to keep 'em on the car.
When aluminum is placed against steel the aluminum becomes a sacrificial metal. It will corrode faster than the steel. It's this corrosion that tends to make the wheel loose on the mating surface. That corrosion acts like a sponge, absorbing your torque values on the fasteners, and creating an uneven mating surface for the wheel against the rotor/drum.
Here's some pics of what I mean. Notice the corrosion on both the rotor and the wheel.
View attachment 7159
View attachment 7160
This corrosion needs to be cleaned off without damaging the aluminum. I like to use a 3M Roloc Clean and Strip wheel on a right angle die grinder. My former boss at the import shop and the tire shop I worked at both had a large electric grinder with a cupped wire wheel attached dedicated to the purpose. The cupped wire wheel allowed us to clean the wheel and still work around the lugs on the car to get the rotor/drum clean.
3M has this handy tool available to clean around the lugs:
View attachment 7164
It gets easier with drums. Pop 'em off and you don't have to work around the studs.
No matter how you do it, you still need to get everything clean.
Here's a comparison shot of the wheel as I started cleaning it.
View attachment 7161
And here's a shot of both the wheel and the mating surface clean
View attachment 7162
View attachment 7163
Hand torque and you're done. (Although some manufacturers do recommend torque sticks.) You can check your torque again after a few miles if that makes you feel better. But you won't have to.
You've also seen guys -or are maybe one yourself - who uses anti-seize on the mating surfaces. That's not recommended as the ant-seize can do what the corrosion has done: acted as a sponge and absorbed the torque values and created an uneven surface for the wheel to mate. Remember, too, all torque values are a dry torque. If you've had luck with using anti-seize or grease, then I'm not going to say you're wrong, but just compare the practice to industry accepted guidelines.
Hopes this helps take some of the mystery out of the reason for the old "re-torque after so many miles" thing.
We've all seen it: take your car to a tire shop and walk out with a receipt that has a disclaimer on it saying that you should re-torque your aluminum wheels after so many miles or you've been talking to a buddy about how we has driving along one night to have one of his tires pass 'em because the the wheel came off.
I worked for a guy one time who worked on a lot of high end imports: BMW, Benz, Porsche, even once worked on a Ferrari and he was pretty anal retentive about following the TIA's (Tire Industry of America) recommended guidelines for proper wheel torque. Later on, when I went to work for a local tire/suspension/alignment shop I had to actually take these training courses, both for pass car and heavy duty trucks.
The other day I had an '04 Jag sitting in the shop, checking the tires over for leaks and doing a rotation when I decided to take some pics and offer up some of my knowledge and experience on aluminum wheels and the proper torque procedures to keep 'em on the car.
When aluminum is placed against steel the aluminum becomes a sacrificial metal. It will corrode faster than the steel. It's this corrosion that tends to make the wheel loose on the mating surface. That corrosion acts like a sponge, absorbing your torque values on the fasteners, and creating an uneven mating surface for the wheel against the rotor/drum.
Here's some pics of what I mean. Notice the corrosion on both the rotor and the wheel.
View attachment 7159
View attachment 7160
This corrosion needs to be cleaned off without damaging the aluminum. I like to use a 3M Roloc Clean and Strip wheel on a right angle die grinder. My former boss at the import shop and the tire shop I worked at both had a large electric grinder with a cupped wire wheel attached dedicated to the purpose. The cupped wire wheel allowed us to clean the wheel and still work around the lugs on the car to get the rotor/drum clean.
3M has this handy tool available to clean around the lugs:
View attachment 7164
It gets easier with drums. Pop 'em off and you don't have to work around the studs.
No matter how you do it, you still need to get everything clean.
Here's a comparison shot of the wheel as I started cleaning it.
View attachment 7161
And here's a shot of both the wheel and the mating surface clean
View attachment 7162
View attachment 7163
Hand torque and you're done. (Although some manufacturers do recommend torque sticks.) You can check your torque again after a few miles if that makes you feel better. But you won't have to.
You've also seen guys -or are maybe one yourself - who uses anti-seize on the mating surfaces. That's not recommended as the ant-seize can do what the corrosion has done: acted as a sponge and absorbed the torque values and created an uneven surface for the wheel to mate. Remember, too, all torque values are a dry torque. If you've had luck with using anti-seize or grease, then I'm not going to say you're wrong, but just compare the practice to industry accepted guidelines.
Hopes this helps take some of the mystery out of the reason for the old "re-torque after so many miles" thing.