Need help with steering wheel shake at speed

[pablom2c]

Hi, I need some help please I have a 135i 2008 with 60,000 km / 37,000 miles. I have a steering wheel shake/vibration that starts around 50 miles per hour and remains at speed, it is not felt on the seat, the whole car doesn’t shake or vibrate, it is only a rapid shake of the steering wheel even though it’s very subtle it is annoying and to me is not normal. It doesn’t happen during breaking. Before I had steering wheel shake when breaking, and I changed discs and pads and it disappeared. My shop tells me they can’t feel the shake, but my brother has an E92 335i N54 and his car is not like mine. Maybe I am overly sensitive to the car but I know when something is not 100% right.

A few months back by accident I hit a rock on the road with my front left tire without any obvious damage, but when I checked the car two wheels were a bit bent, and they were fixed and they now balance perfectly (OZ Ultraleggeras was a bad choice for our bad roads filled with potholes, didn’t think that they would be so soft). They also have the metal OZ hub centric rings installed. I have already tried balancing at different places and same result everything appears OK. I have heard people online recommend road force balancing but I have not found a place in my country that has this machine.

Back in November I also installed Bilstein B6 dampers (keeping the OEM springs) and the OZ wheels which are 18x8 front et 34 and 18x9 et 40 at the back with Continental Contact Sport 5 (225 40 18 and 255 35 18). To me everything was perfect, I believe this problem started since I hit that rock recently.

I requested my shop to check my whole front suspension and found my sway bar end links in bad shape. So I installed new sway bar ends links, tie rods, and m3 control arms. Before changing these parts the shake was at a lower speed around 40-60 miles per hour, and would disappear 65+. Now after changing these parts the shake moved up from 50 miles an hour and up.

Could the width and offset of the wheels cause this shake? Are they too extreme for this car? Maybe the actual tires are bad? When balancing they don’t have any bulges they seem fine from the outside maybe the internal bands are in bad shape? We also checked bearings by moving the wheel in the air and everything seems solid, I also don’t hear any roaring noise from the bearings. The suspension doesn’t have any knocks or noises, and the steering seems solid and tight besides the shake. What else can I check? I think one last test will be to try the car with the OEM wheels. I can also buy new tires, but I’m getting tired of throwing money at this. Maybe change the rear bushings also? This small shake is taking away the joy of driving my car, it feels broken. I’m about to go out and buy a Wrangler so I can forget about potholes and bad roads but I know I will greatly miss the handling and speed of my car, and then regret selling it since in my heart I’m a “fast car” type of guy and not really a jeep guy.

I’ve also read tons of threads and many E92 cars and even M3s complain about the same problem as me, some just live with it but most get fixed by changing bushings or balancing so I’m completely lost on what to do.



Sorry for the long post and thanks for your help.

[chris_flies]

I have a slight shake that comes on strong, right at 70mph, and recedes a bit after 90. I think it's an out of balance wheel in my case, as rotating tires moved it to the back, but it could also be tiny flat spots on the tires from sitting, or from hard braking on track days. There are so many variables. It could be as miniscule as uneven brake pad material transfer (I doubt the car is that sensitive)...

[________]

On mine it was bent wheels.

[MightyMouseTech]

Dealer should have a road force balancer. Although, if the rims are visually straight, only other option is going to be the tires.

[Thunderguts]

I have absolutely no shake at highway speeds. You probably hear more complaints because our steering is so precise that amplifies any irregularity. It's almost certainly your wheels or tires. There are, of course, many factors in play. Maybe one of your pressure sensors is loose and throws off the balancer. Maybe the bent wheels weren't fixed that well. Maybe try to swap wheels with someone to see if that takes care of it.

[Zombie_Head]

Lots of things to check with regards to vibrations.

Jack up the car, grab the wheel with both hands (one at 3 o'clock and one at 9) and shake the wheel in and out, there should be zero play. If you are able to move the wheel, meaning if the tie rod moves, that is fine, but you are looking for excessive play. Do the same at 12 and 6, if you notice and small movements without the wheel actually moving, then you may have a bad ball joint somewhere (upper or lower arm or even tie rod), do this on each corner.

Since you are not reporting any noises when turning, it could mean that the shocks/mounts are good.

If all checks out, rebalance each wheel. Could be a wheel is slightly off balanced, or worse case a small bend in a wheel, a specialist can help.

It will not hurt to double check all suspension bolts, i do this every 10,000 kms which is excessive i know but i do a lot of track days, last thing i want is a suspension component coming off at 160+ cornering speeds. And for peace of mind, check the wheel bolt torques as well.