Car feels unstable at high speed

[5ABIVT]

I wanted to chime in on this post. 2016 M4 bought at 35k miles. Car was rock solid and at speed is straight and solid.

Just hit 46k miles in the car, and last week I noticed this uneasiness at speed. As if there were gusts of wind and causes me to make ever so slight input changes to the steering wheel. I also noticed that at a stop, there is looseness at center in the wheel. Moving the wheel left to right just about 1/2 inch side to side fees loose, but this goes away when moving.


I’m quite confident something is up with the steering. My guess is the bushings and I’m trying to figure out if any of the replaceable ones can have an impact on steering toe if there is any play in the rubber. The car felt like there was some toe in at speed keeping it straight and not requiring much input when I bought it and now it feels like the toe rods ends are worn at speed.

Looking into changing all the front control arm bushings with aftermarket. Will report back if it is fixed !

[Kev608]

I'd try a monoball thrust arm bearing.

[TanzaniteBlue]

182 mph, rock solid.

[Spun Crankhub]

I effortlessly pulled to 175 mph a couple months ago, and car felt solid as a damn rock. Might be time to check suspension components for wear.

[2011ninja]

Originally Posted by TacoChris

I effortlessly pulled to 175 mph a couple months ago, and car felt solid as a damn rock. Might be time to check suspension components for wear.

Originally Posted by TacoChris

I effortlessly pulled to 175 mph a couple months ago, and car felt solid as a damn rock. Might be time to check suspension components for wear.

Solid 163 like a F16 Raptor 🦅

[behindthen0thing]

Originally Posted by TanzaniteBlue

182 mph, rock solid.

Hell yeah that's what I'm talking about

[Suds]

I have the same loose feeling in the steering wheel when stopped, my feeling it’s in the way the electric power steering is programmed.

Originally Posted by 5ABIVT

I also noticed that at a stop, there is looseness at center in the wheel. Moving the wheel left to right just about 1/2 inch side to side fees loose, but this goes away when moving.

[BoostinLI]

What tires do you have? Are they worn out? If so time to swap them. Same situation I had went with mpss and all is perfect with an alignment. Good luck

Originally Posted by 5ABIVT

I wanted to chime in on this post. 2016 M4 bought at 35k miles. Car was rock solid and at speed is straight and solid.

Just hit 46k miles in the car, and last week I noticed this uneasiness at speed. As if there were gusts of wind and causes me to make ever so slight input changes to the steering wheel. I also noticed that at a stop, there is looseness at center in the wheel. Moving the wheel left to right just about 1/2 inch side to side fees loose, but this goes away when moving.


I’m quite confident something is up with the steering. My guess is the bushings and I’m trying to figure out if any of the replaceable ones can have an impact on steering toe if there is any play in the rubber. The car felt like there was some toe in at speed keeping it straight and not requiring much input when I bought it and now it feels like the toe rods ends are worn at speed.

Looking into changing all the front control arm bushings with aftermarket. Will report back if it is fixed !

[deli333]

Originally Posted by 5ABIVT

I wanted to chime in on this post. 2016 M4 bought at 35k miles. Car was rock solid and at speed is straight and solid.

Just hit 46k miles in the car, and last week I noticed this uneasiness at speed. As if there were gusts of wind and causes me to make ever so slight input changes to the steering wheel. I also noticed that at a stop, there is looseness at center in the wheel. Moving the wheel left to right just about 1/2 inch side to side fees loose, but this goes away when moving.


I’m quite confident something is up with the steering. My guess is the bushings and I’m trying to figure out if any of the replaceable ones can have an impact on steering toe if there is any play in the rubber. The car felt like there was some toe in at speed keeping it straight and not requiring much input when I bought it and now it feels like the toe rods ends are worn at speed.

Looking into changing all the front control arm bushings with aftermarket. Will report back if it is fixed !

I am having exactly the same issue, let me know if you find a solution

5ABIVT

[thestimp]

The trunk spoiler or front diffuser not installed properly can do this. Mine had a fucked up front lip that made it feel like I was constantly battling the wind gods.

[deli333]

Originally Posted by thestimp

The trunk spoiler or front diffuser not installed properly can do this. Mine had a fucked up front lip that made it feel like I was constantly battling the wind gods.

this made me think actually, can anyone else comment on it?

[Tommy L Garage]

Originally Posted by deli333

this made me think actually, can anyone else comment on it?

I second that. My first track with the car was 3 years ago and I had an aftermarket lip installed which didn’t sit right. At high speeds the car felt twitchy. Then in one of the Track photos I noticed that the lip is actually deforming the bumper and pulling the whole thing up. Needless to say I removed it the next day.

I now run the lightweight lip which points down and is bolted to the bumper with nuts and bolts. Zero issues now at 145 mph

[swagon]

Originally Posted by Tommy L Garage

I second that. My first track with the car was 3 years ago and I had an aftermarket lip installed which didn’t sit right. At high speeds the car felt twitchy. Then in one of the Track photos I noticed that the lip is actually deforming the bumper and pulling the whole thing up. Needless to say I removed it the next day.

I now run the lightweight lip which points down and is bolted to the bumper with nuts and bolts. Zero issues now at 145 mph

This is why BMW puts reinforcement bits behind the bumper for their lips, be it M Performance, CS or GTS.

[thestimp]

My Car has the Mperformance package but the lip must have been replaced with a generic black plastic one at somepoint, which is why it was all crazy. Replaced with OEM and never had the problem again. My 2cents. But now I have the 10810c error and leaking intake reservoir... joy...

[deli333]

Originally Posted by Tommy L Garage

I second that. My first track with the car was 3 years ago and I had an aftermarket lip installed which didn’t sit right. At high speeds the car felt twitchy. Then in one of the Track photos I noticed that the lip is actually deforming the bumper and pulling the whole thing up. Needless to say I removed it the next day.

I now run the lightweight lip which points down and is bolted to the bumper with nuts and bolts. Zero issues now at 145 mph

i have aftermarket wing, i will take it out and try.

i took out my splitter, it didnt make any difference. i will try one by and see if it makes any difference. the weird thing is car is extremelt stable until 80mph then it starts..

thanks for exhaust leak video btw it was spot on 😅

[chipper1]

Its alinement 100% take it to the dealer not some alinement shop! have them look over suspension too.

[sxychubles]

Originally Posted by michaelalex17

My 2015 M3 with active suspension feels unstable above 100mph (tested in Mexico). I am recently coming from an e92 335i and that car felt very planted all the way to 155. When I am going 100+ on a perfectly flat and straight high way in the m3 I have to make a lot of steering corrections just to keep it straight and it doesn't feel as planned. The sensation is almost like is a gust of wind were blowing the car from side to side. I have tried all the different steering and suspension modes, but the second I go over 100mph the car starts to feel twitchy and not planted. The tires are filled to 33psi all around (door insert recommended tire pressure) which honestly seems low to me would think it should be around 38 front 40 rear. I also thought it could be an alignment issue but the car tracks perfectly straight if I let go of the wheel. Any thoughts on this issue would be greatly appreciated. Thank you

Did you ever solve this?