Installing new wheel studs on new rotors???

I've installed new front rotors on my 1st Gen RX7 including new studs. I cleaned the threads on bith the studs and the hubs with a little brake cleaner, then I used red lock tite and cranked them in about 1 turn past snug. I torqued the lug nuts at 70 lbs. After only 5 miles I lost two studs from the drivers side hub and the other two were quite loose (passenger side studs seem fine). The hubs are Brembo and I don't believe the problem is because of poor quality OEM steel. Should I be using something like epoxy or JB Weld to??? I have a track day coming-up and am worried about losing a wheel. Thanks in advance for any advice.

Not sure of the RX7 but I recently installed screw in studs on my A1 VW.

I tightened a bit over 100 ft-lbs and installed my wheel shortly after installing the hubs. Car sat overnight before I drove it.

How long did you wait before using the car? My guess is that the 70 ft-lbs isn't tight enough. When you put on the wheels , you broke the locktite bond.

Dunn'o about anybody else, but Toyota recommends pulling the stud through with at least 130 ft/lb using a lubricated block and threads. If the head doesn't bottom out - it's not tight enough. I've never lost one, and I've replaced every stud on the car at least once. BTW - wheel nut torque on mine is 76, FWIW.

Ishod, seems like you did everything right. Just make sure the studs are screwed in pretty snug( can't give you a torque # since I use an allen wrench). Red locktite worked good for me. When the rotors were done, the studs went with them because they were a bear to get back out and also, they do streatch after a while. Max torque on the wheel nuts is 75 lbs. Any more than that, you'll risk pulling the studs back out. I think you may have had a problem because the studs were not into the rotor far enough. Make sure you get them in up to the knurl on the stud and all should be fine.
Ray

The problem may be the studs. Where did you get them?

I ask because I've had simular problems with my 1st Gen RX7. The problem was not the rotor but the studs. I got mine from Mazdatrix. The steel they are made of turns out to be real soft. The threads and the allen head both stripped out.

Thank you all for your responses!

Joe, In answer to your comment I waited 24 or so hours before driving the car.

ITANorm, the Brembo hub has an open stud hole. There really isn't any way to bottom-out the stud except that the stud does have a knurl (thanks moto62 for that reference) between the hub threads and the lug threads.

moto62, I used red locktite. I even snugged the studs more like 1/2 to one full turn past snug. I bought the car with a spare set of used front rotors and worked my ass off to get one of the studs out of the spare. It looked like it had been seated with epoxy (grey color). Which is why I'm thinking about installing new studs with JB Weld???

itaracer, I got the studs from 7's Only Racing, and yes there is a possibility that they are soft (how can you tell?). These people are great and have been very helpful with advice. I will buy as many parts from them as possible because of their willingness to share their knowledge. Their advice on this issue is... 1) clean the stud threads and the hub threads with a little brake cleaning fluid, 2) apply one drop of red LOCKTITE and then screw the studs in until tight and crank 1/8 turn more, 3) let sit for 24 hours and then mount the wheels using 80 lbs of torque on the lugs. I did all of this and then lost the lug nuts anyway???

Again, thanks for the comments. My plan is to reinstall the studs on the front drivers side using JB Weld. Race weekend coming-up and I don't need to be concerned about losing a wheel.

Any input is appreciated.

ishod, install studs that are long enough to pass through the hub mounting flange & install nuts on the back side of the mounting flange.

Many of the studs have roll formed threads which may not be the best quality.

Talk to Brembo about the issue.

Have Fun http://Forums.ImprovedTouring.com/it/wink.gif
David

Screw-in studs should not be "tightended" once they are threaded in to the hub. Think about what you are doing. If the studs threads are 'topped out' in the hole in the rotor, if you continue to turn the stud, are you putting more threads on the stud? No. You are twisting the stud. This can lead to all kinds of problems.
Here is a link to ARPs website:
http://www.arp-bolts.com/pages/products/pa...ks/how_tos.html
I know this is for head studs, but the principle is the same.

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Rodney Williamson
#93 IT7
www.titaniummotorsports.com