Bent Wheels?!

[Subaru_Nation555]

When I had alignment done, I also had my wheels balanced because there is a vibration over 60 mph. I noticed that they put three big weights on one side of one front wheel and two big weights on the other. I assume that this is an indication that the wheels are slightly bent. So recently I noticed a clunking making any right turnover 10mph. Thinking it was an axle or some other problem, I decided to check the tightness of the lugs on a whim. Low and behold most of the bolts were loose on the left side, and some on the right. I tightened them all back up securely and went on my way. A couple of days later, some of the bolts are loose again. So my question is: are the lugs coming loose because highway driving or any other is causing then wheels to vibrate them off. This seems like a silly questions but its kind of scary knowing that they keep coming loose. Thanks.

[evolutionmovement]

Good, I have a lot of experience with this. Bent wheels can't be fully balanced, so you'd likely still notice a vibration. As for the nuts coming loose - what spec are you using? My old bent wheels' lug nuts never came loose, but my perfect Forester wheels have to be retightened way past spec after a few 100 miles of driving after reinstal. The spec is 65 ft/lbs, which is almost as bad as hand tight. Even 80 gives me trouble, so I go to about 95 in two steps - 1st to 65, then to 95 and that seems to work.

Steve

[BAC5.2]

The Rota's never back out. They are always pretty snug.

It's probably got to do with the type of lug nut you use. I use conical nuts for my 17's, and use them on the WRX wheels as well.

[evolutionmovement]

Good point, Phil, I reused the ones from the old wheels and they kind of stick out like Ben Hur (which I kind of like).

Steve

[professor]

The lug nuts they sell at Pep Boys fit perfectly (McGard I believe), so the taper on stock Subaru wheels is the most common, 45 degrees. Make sure that is so on your lugnuts.

You should always tighten in a star pattern, and do it twice, finishing with a torque wrench.

Is there grease or oil on the threads or seating area ? This is a common mistake and will cause the lugnuts to loosen easily. Most alloy torque specs are only 60-90 ft-lb and should be fitted dry. Use solvent to remove any lubricant if it is there.

My BMW manual says directly that ugs need to be re-torqued after driving a bit, and I think that makes sense. It also catches mistakes where you may forget to fully tighten one or more (I'm certainly guilty of that more than once)

Check for bent wheels by putting the car on jack stands, starting the engine and running the wheels. If they are bent, you'll see it easily. make sure to look at the inner side rim as well, it may be bent there only. You'll also find bubbled tire sidewalls as well, very common with bad vibrations, mostly from someone curbing the tire.

[BAC5.2]

Professor - VERY good point about grease or oil on the threads. Not only does it allow the lug to back out easily, it also makes it VERY easy to over-tighten the lug nut. Overtightening is BAD, as you can damage threads and stretch the threads slightly.

Every thing says you NEED to check the lugs after 100 miles of driving to make sure they are still tight.

[Subaru_Nation555]

I checked the lugs for any greese or oil. I cleaned them all off and tightened everything properly. I hope everything stays nice and tight. Thanks for the replys. I might just use this as an excuse to get new wheels though. My stockers look like crap.

[93Leg-c]

If you find that your wheels are not bent . . .

Take them back to where they balanced it and have them rotate the tire around the rim 180 degrees. Usually that amount of weights indicate that the heavy side of the tire is matched up to the heavy side of the rim. Then have them balance the tire(s). You'll usually find they end up using a small weight and the vibration gone. With those kind of weights on, my experience says you'll never get the vibration out.