alignment?...what do you guys think?

hey all, got a '99 cab with brand new tires and still have a front end noise that sounds rotational and picks up with speed. the noise was present before the new tires (i thought it was the tires before) but afterwards no improvement. the old tires were worn evenly in the front and typical inside wear on the rear. i've put 30,000 miles on the car since i've owned it. i've had the car for 2 years and never had an alignment. i've autocrossed it and drive it pretty hard. the car rolls straight down the road and doesn't pull one way or the other. the noise seems to accentuate in corners. is this just me or wtf? thanks for any input.

Have your wheel bearings looked at. Raise front of car, grab wheel at the 12-6 o-clock position and rock. You should not feel any play, but a tiny bit is ok (definitely a feel technique). If there is enough play for you to hear/feel on the road you should definitely be able to detect that by rocking.

yeah i thought about the wheel bearings but the car only has 37,000 miles on it, i also thought maybe i have a warped rotor...the noise is not very loud but present...the car has 2 months left of warranty. guess i'll have to take it in and pray not to get raped. thanks for your input.

It's not uncommon for the bearings to go bad early. My friend with a 993 had to replace his at 32K miless

that gives me some piece of mind...thanks eli k

Yep had my bearings replaced on the front end done..they went around 35K mark... LOTS-O-TRACK miles...... Bearings are like head lights.....if you do one side you should just as well do the other :-) Save you travel time to the shop ....because its just a matter of time. If your rotor(s) is warped you will be able to tell with just a slight preasure of the brake pedal. You will feel it catch and release rather than a constant slow down if you take your foot off the brake you should feel most of it go away.

Eliminate the noise being caused by the tire tread. Lower the peassure to 20 - 25 psi and if the sound changes, it is the tires. Or drive it on wet pavement and listen for a change.

thanks guys, that was really helpful advice. i'll try both of your recommendations.

FWIW, I now have 80k on my c4 and every single time I have ever had road noise it was because of the tires. If you get one tire just a little out of balance and drive on it, it only gets worse. Every time that has happened to me I have had to start over again with new tires. Especially on the front of the car. I have had the car aligned a couple of times and I found that the spec alignment for the rear wheels still had the tires wearing on the inside shoulders. I finally put the car on my own lift and took all of the camber out of the set up. To do this on my car required the cam nuts be set all the way to their lowest setting. FINALLY, I have had a set of tires wear evenly for a whole driving season........fourth (rear) set on the car. I tweaked my front alignment (toe) a couple of times based on tire wear and finally got that right also.....The "shelerdip" just couldn't seem to get it right and I got tired of being their pigeon.

point taken gretch, thanks. i had her out tonight, played with the pressure, drove on wet pavement - no change. brakes feel fine. i'll jack her up next day i have off and check the front for a bad bearing. if the wheel on either side moves at all i'm going to replace the bearings in both. cheap fix if thats the case. if not i might have to check the alignment out. you guys have been very helpful with your suggestions, thanks

These cars always wear on the inside more than the outside because of the mild negative camber. It's why these cars handle the way they do. If you ever track your car you'll want even more negative camber. If the insides are wearing much faster, you're not cornering fast enough.

My car is a commuter........long highway miles.....In that application the negative camber is nearly usless, and needlessly expensive. For regular street use, the vast majority of drivers will not challenge the car anywhere near 75% of the car's capability. I am not suggesting anyone do this on their own (remove the negative camber) if you want to try it, get the advice of someone you can blame later if it doesn't work for you.

True. But I haven't been on the track in two years, and I've managed to get a lot of miles out of Michelin's Pilot Sport tires (the ones with the V and W grooves that they don't make anymore). And I run a bit more negative than stock. I switched my rears to Pirelli P-Zero Ross and they're also wearing nicely and even.

jacked the car up today and couldn't feel any play in either wheels using force at the 12 and 6 position. every wheel felt very solid. i played with the pressures again...dropped all 4 wheel pressures down to 22psi and maybe the noise was a little louder but not noticeably. still have the same rotational noise that gets louder with speed and on corners. i'm starting to think maybe its just me but i don't remember the car making as much noise going down the road 6 months ago. is it possible a bearing could be starting to go and still have no play in the wheel? is it possible that a car out of alignment would have these problems? we'll find out. last set of tires showed typical wear for a 911. fronts were even and had plenty of tread left compared to rears. rears had inside wear down to the secondary rubber. tires were put on 6000 miles after i bought the car. i then put 24,000 miles on them before having them replaced just recently.

I'd let another 996 owner drive your car and see what he/she thinks. Since the wheels are tight, you can rule out the bearings. Could also be the brand of tire. I recall Khumo's making a bit of noise on my '78.

i'm running michelin pilot sport ribs...drove my buddies boxter s and it was quiet compared to mine and he was running kumho. he noticed road feel/vibration in my steering wheel and the noise but i don't think my steering wheel feels any different. i will get another 996 driver to check it out.