2003 C-5
When backing out of the driveway, wheels turned sharp in either direction, nearing full to the stop, my wheels have a popping action. It's like I'm running over a rock. Only in reverse. Became more pronounced after a wheel alignment.

Any ideas? Suspension? Bad tire?

Thanks

 

Since the only thing that you mentioned that is different, is the wheel alignment. Therefore, I'd say the alignment isn't quite right. My first guess would be messed up caster....

 

Popping, front or rear??

Rear popping

 

My guess would be the fronts....

 

You mean you get a popping sound in the suspension?

Usually the wheels go flat when they make a pop sound...

I doubt the alignment caused a popping sound unless one of the adjustment cams was left loose. That should be easy to tell though because the car would be all over the place when the alignment shifted to a way off position.

I'd suspect you have a worn part, like a sway bar end link, a tie rod end or a ball joint that would be causing that. You could also lube the sway bar bushings to see if that helps.

 

Thanks, guys

Yes, the popping was with the front when I turn my wheels almost all the way one direction or the other. Hard to explain, but it reminds me of backing a wheel over a walnut and when it crushes it, the wheel shimmies. Kind of like when you hit 50 years old and, among other things, your shoulder pops when you rotate your arm in one direction. I'm going to drop by the place that did the alignment tomorrow and see what they say.

 

The search engine is your friend, been discussed here off and on for the last 10 years.

They all do this, it's the effect of ackerman (or maybe anti-ackerman) when turning full lock at low speed. One tire is turning more than the other and it eventually "hops" after the tires wind up and then pop back. If you are going faster it doesn't happen, it's only a low speed thing. It can happen going forward or backward, it's nothing to be concerned about.

Resetting the toe can effect it, but that doesn't mean the toe isn't set right, since they all do it. I'd look at the alignment specs from the last alignment and if it's where it should be I'd ignore it.

 

Awesome! That's very reassuring. I did a search, but didn't see a lot on it before posting. Probably didn't use the right term for the search.

Thanks again, everyone. Appreciate the help.

 

I had an alignment done on a car years ago and it also did this. It was bad enough to destroy 2 new tires in 50 miles. Took it back to the shop the same day for satisfaction. The tires were toast. I'd be concerned if I were you. This is NOT normal. Might have happened to others also, that doesn't make it right. Suffice to say, mine does not do that. So, one of our cars is not working properly. And, I'm not gonna get mine set up like yours so mine is "Normal", if you get what I mean.

Oh, and find a new shop. That one will be out of business soon. The one I went to lasted about another 2 years and they went under. Never did know why...

 

OK, here's a twist in the story. Took it back to the shop that did the alignment. They said the alignment was fine, but the problem was my differential. To be specific, my diff fluid had broken down and the limited slip wasn't so limited. The thought being that when turning the front wheels to almost full stop at low speed, the diff was not allowing slippage and in fact turning both rear wheels at the same speed. This, in effect was trying to push the car in a straight line but with the front wheels turned, two things happened. One, as the rear wheels were trying to push the car in a forward motion, they were fighting against the turned front wheels. The popping action was actually the turned front wheels being pushed sideways and "skipping" across the pavement. The second thing that was going on was the rear wheel that was supposed to be turning at a slower speed than the opposite wheel in a turn was actually going the same speed because the diff was not allowing slippage to compensate for the turn. This means the rear wheel with the short radius was spinning the tire on the pavement.

A different shop that I took it to a year and a half ago "supposedly" change the fluid, but I can only confirm that I paid them for it. So, I'm going to change the diff fluid myself this weekend, but I wanted to see if anyone else had heard of this. Frankly, I can't see it working like this but stranger things have been known to be true. Like Justin Bieber making more money than me. The coincidence that this became extremely more pronounced AFTER the alignment has me suspect it's still in the front end, but the alignment is also in conjunction with some really cold weather moving in meaning the diff fluid could be to blame. The popping does seem to be slightly reduced after driving the car for a while.

Sorry for the long post, which I hate reading almost as much as I hate writing.

In any case, I'll repost after the lube change and let you know how it worked out. In the mean time, I'd like to hear others take on this.

 

My car tends to chirp or squeal a bit on cement such as when turning sharply in a parking garage but I've never had it push the front wheels sideways and it's never "popped". I just hear it, not feel it. Maybe it's a run crap thing? I have larger than factory rims and good rubber on my car.

Why don't you post the alignment specs so we can tell you if the place is full of bS or not?

 

If you've been driving it, you'll be able to see feathering on the edges of the tread by now. Either on the inside of the fronts or the outside. As to the diff being locked up and skidding the fronts. Even if the rear was solid, the rear tires will never have enough traction to make the front skid sideways. That is complete bs. Simple as that. Remember, you're talking about ONE rear wheel having enough traction to overcome a 1.5:1 leverage and two front tires, with an engine over them to boot. One rear tire will skid long before.

Do yourself a favor and go to another shop...

 

The reason it could push the front tires like this is because the diff isn't slipping. YOU DON'T WANT IT TO SLIP. The more the diff slips, the faster it wears out.

I explained it earlier, the tire hopping is common. If the alignment isn't messed up, don't worry about it. If you've recently changed the diff fluid, you don't need to change it again.

If a limited slip diff slips a lot it will wear quickly. Don't go changing the fluid or putting in more friction modifier, you want the diff to stay tight.

The geometry of these cars is set up for high speed handling. At the end of the steering lock the outside tire (when backing up) is turned to far and it winds up and hops. It's just the geometry, but things like toe setting make it worse. I'm sure if you were at the other side of the toe spec it might go away, but it's no big deal and you really need to just get over it.

 

Solofast? Are you using a controlled substance too much? Listen man, this is NOT normal. Go test drive a brand new Corvette and tell them all you want to do it back up in a couple circles in the parking lot. Do that and tell me how normal it is for the front wheels to be hopping. Are you serious?

His alignment is hosed.

 

Still waiting for the after alignment numbers to be posted....

 

You're both (potentially) correct. What Solofast says is true about the popping/hopping that can happen in some cars under full steering lock. Most cars don't exhibit this effect simply because they don't have enough traction, and the tires scrub quite easily. But put some wide, super sticky tires on your car, and do a low speed full lock turn and there's a good chance you'll feel that rhythmic popping from the inner tire. Now as to your testdrive of a new C5, read that boldfaced part again and bear in mind the qualities of the tires that GM put on our C5s from the factory that earned them the name "runcraps".

However I'm not going to promise that what the OP is experiencing is normal. It would be good to know the alignment specs as well as the type of tires on the OP's car before making any conclusions.

 

I took a car for an alignment once, and afterward, it did this same thing. I had owned the car since new. It never did this when new. It only did it after the alignment was f(*&$%ed up. I now drive a C5 (though not lately ). It does not do this. If it did, I would not be very happy. As to driving a "New C5", I don't care what car you use to test. A 0 miles C5, C6, C7. Pick one, it won't do this. Run a poll on this forum and ask how many C5 users have this issue. I bet the number ain't many. Very nearly 0.

 

My car has done it since day one, but right after I got it I put an aggressive performance alignment (-2 deg negative camber up front). I honestly don't remember if it did it when it was stock, since that was only a few days, but my car is a Z06, and that has tires that are sticky, and have a softer sidewall than the runcraps on the base car. Big difference. K-Spatz's car might not do it if he has runcraps or junk tires on it, but every Z06 I've driven did it, and that's where I'm coming from.

The stiffer suspension, different tires all can make things behave very differently. Just because your vert doesn't do it doesn't mean the OP's alignment is screwed up. I regularlly check my alignment (twice a year during the racing season) and I know exacty where it is, and it isn't screwed up, and my car does it like clockwork. It did it on the Goodyear F1's that came on the car and it does it on the tires that are on the car.

And if you do a search on this forum as well as on the Z06 pages there were plenty of threads that talk about the subject back in the 2002-2004 time frame. All of those theads note that it's normal and nothing is screwed up.

 

I'd like to hear what you toe specs are. Sorry, but I'm just not gonna buy this is normal. Might be if you're running some sort of track setup, but for a street driven car, there is just no reason for this to happen. If you don't mind it, that's fine. I would mind, a lot. Especially considering the tire wear.

 

You gotta be f'king kidding me dude. I see a thread pop up about this from a new owner like once a month. I don't need to run a poll, just do a damn search. Don't limit yourself to this forum either. What Solofast describes is a common, well documented thing whether you realize it or not. If you've only ever driven a Corvette with Runcraps then I can easily believe you've never felt this. That doesn't mean it isn't normal.