vibration at certain speeds only - e70 X5

[rh71]

First, the stock setup never vibrated... then I bought replica 20" rims and Toyo Proxes S/Ts staggered, 275 front / 315 rear. There has been a vibration in the seats (not steering wheel) at 60mph-80mph the minute I got on the road. It's there everytime on every road, not random. Had them re-balance and still the same. This was a year ago. Last week I finally got it road-force balanced, but the problem persists. First I had them do the rear two, it felt a little bit worse actually. Then the front two and it's better, but still there. It feels like a massage but it drives me nuts knowing it'll be there when I accelerate - and decelerate (through the same mph range) - no braking.

The guy says they were road forced and spinning perfectly. Shouldn't that mean zero vibration regardless? Did they not do road-force properly? I'm not sure if they actually moved the tread around the rim like the machine is supposed to indicate. Right now there are weights stuck onto the inside of the rim (inner and outer half for a dynamic balance). Others say a bad tire can cause this and there's nothing that's going to fix that except replacements. Is that also true?

I suppose my only recourse is to prove that the rim isn't out-of-round (both places that balanced said it wasn't) and that the tire itself is causing this and claim the Toyo warranty.

Is it possible something in the suspension may cause this and not the wheels/tires?

Thoughts?

[900TVT]

Any number of suspension parts will cause a vibration while driving.

If you're only experiencing vibration at certain speeds, I'm pretty sure its a suspension part at fault. If it was a bent rim, you would feel the vibration all the time.

[GunnerNell]

I vote for one of the tires being the problem. However, are the rear wheels alignable (if that's a word)? Every time I've had that kind of vibration -- occurring at certain speeds but not all the time -- it's been balance or alignment. And if it's in the seat of your pants and not in your hands, it's the rears, not the fronts.

[rh71]

I'm also leaning on tires/wheels and not the suspension because this started immediately after I got new wheels/tires on. It's possible that a suspension part was messed with accidentally during the install, but that's remote. The balance shop basically said "it's perfectly spinning now... if there's still a problem have your dealer look at your car". I have an appt in 2 days to do that just to make sure. Then again, I've heard of cases where a balance job was necessary a few times before it was right. So frustrating...

If it's a bad tire, can a balance job even compensate for that?

[M62pwrdE38]

If they were road-forced correctly, they should be able to tell you the loaded radial runout in the tire/wheel assembly; and if a tire or wheel is out of round. Ask the shop for the amount of runout in each wheel/tire, and if its over ~.025" (~25 lbs of force) you will likely have a problem. From there they should be able to tell you if the wheel or tire is the cause of excessive runout. If they can't, then they are not using the road force feature of the balancer correctly. If a tire is out of round by enough, no amount of balancing is going to prevent a vibration.

[GunnerNell]

Sorry to be just guessing here, when what you need is an expert look-see and opinion. I'm thinking "out of round" doesn't explain this. If that were the problem, I'd expect you to feel it at all times. Other thoughts -- you went from stock to staggered. I wonder if the car hadn't been aligned properly -- with weight on the wheels -- whether the new, wider tires would change the physics of how it rolls. I wonder, too, whether you had to install any spacers with your new wheels and whether those might be causing some mischief. Finally, I wonder whether the problem is showing up only now because your new wheel/tire set up is putting unfamiliar stress on the rear wheel bearings, showing some bearing wear that would not otherwise be evident.

[rh71]

Sorry to be just guessing here, when what you need is an expert look-see and opinion. I'm thinking "out of round" doesn't explain this. If that were the problem, I'd expect you to feel it at all times. Other thoughts -- you went from stock to staggered. I wonder if the car hadn't been aligned properly -- with weight on the wheels -- whether the new, wider tires would change the physics of how it rolls. I wonder, too, whether you had to install any spacers with your new wheels and whether those might be causing some mischief. Finally, I wonder whether the problem is showing up only now because your new wheel/tire set up is putting unfamiliar stress on the rear wheel bearings, showing some bearing wear that would not otherwise be evident.

no spacers, it was vibrating before, and then after the wheel alignment where they mess with the camber it was still vibrating. I'm bringing it into the dealer tomorrow for another issue as well. I was able to confirm yesterday that the road-force shop indeed used a GSP9700 Hunter machine. Whether they used it right or not I'll determine after tomorrow.

The other issue I mention is a creak from the suspension... I was able to duplicate it this morning when going up a public driveway which had a water grate that drops back down a bit so my vehicle went up and immediately back down... as it bounced, the creak sounded along with it. I'll see what the guys in the susp threads think...

[samger2]

The OP never said this...but stock IS staggered...at least the 275 - 315 setup is a stock setup.

At any rate, I as well would lean toward an out of round tire...BMW chooses their tires for a reason, because they've done extensive testing on those tires and that's what rides the best on their vehicles. I know alot of people love Toyos, but I myself consider them to be a mid grade tire as opposed to the top of the line Michelin that comes from BMW in those same sizes.

Basically I don't see the larger (if in fact they are larger) tires and wheels causing undue stress on the suspension components...and I say that because you can pretty much purchase any BMW and then upgrade to to sport wheels and tires...but none of the suspension components are changed when upgrading the wheels and tires. And there is never any stressed suspension in that case.

You've pretty much isolated the problem. No vibes with OEM stuff...you put non OEM stuff on and you get vibes...you've had them rebalanced and it helped somewhat but still have vibes. So long as a wheel isn't bent I'd say you're looking at one maybe two bad rear tires.

[samger2]

The OP never said this...but stock IS staggered...at least the 275 - 315 setup is a stock setup.

At any rate, I as well would lean toward an out of round tire...BMW chooses their tires for a reason, because they've done extensive testing on those tires and that's what rides the best on their vehicles. I know alot of people love Toyos, but I myself consider them to be a mid grade tire as opposed to the top of the line Michelin that comes from BMW in those same sizes.

Basically I don't see the larger (if in fact they are larger) tires and wheels causing undue stress on the suspension components...and I say that because you can pretty much purchase any BMW and then upgrade to to sport wheels and tires...but none of the suspension components are changed when upgrading the wheels and tires. And there is never any stressed suspension in that case.

You've pretty much isolated the problem. No vibes with OEM stuff...you put non OEM stuff on and you get vibes...you've had them rebalanced and it helped somewhat but still have vibes. So long as a wheel isn't bent I'd say you're looking at one maybe two bad rear tires.

[VIPLINE]

Are the wheels hub-centric?

Maybe the tires weren't balanced properly.

[rh71]

*UPDATE* so I had the dealer take a look and they put the vehicle up on a lift with all 4 tires spinning slowly. With the right rear tire held to a stop, the left spins faster, and that's when it was noticeable. From a profile (side) view, the tire actually looks like it's bulging toward the front of the vehicle during spinning, quite a sight. Couldn't really tell if the rim was doing it too, causing the tire to flex further out... but it was clear the tire is not spinning perfectly round from a side view. I suppose I'm going to a Toyo authorized dealer to claim the warranty. Hopefully I won't need to pay another $30 to roadforce it after... and hopefully the right side is fine - nothing was obvious on that tire.

Oh and BTW, they hit something while under their care. The dealer is now responsible for ordering me a whole new right front panel.
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