[boxrick]

Sorry for the thread bump, but I recently purchased an F36 420d Grand Coupe and its doing exactly the same thing.

I have just had new tires all round, new track rod ends, 4 wheel alignment and new pads and rotors.

I am getting sometimes the car will be heavy on the steering and other times it will be really light. It also feels somewhat disconnected and loose. It does this at high speeds and low.

Garage had it, but couldn't see anything obvious and stated it could be:

Shock Absorbers
Lower Control Arm
Lower Wishbone

Given this is driving me mad, I am likely going to be throwing money at the problem till it goes away. With that in mind, where would the 'smart money' be to try and get replaced to hopefully resolve this issue? Car is at 91k miles.

[Allworth]

Originally Posted by boxrick

Sorry for the thread bump, but I recently purchased an F36 420d Grand Coupe and its doing exactly the same thing.

I have just had new tires all round, new track rod ends, 4 wheel alignment and new pads and rotors.

I am getting sometimes the car will be heavy on the steering and other times it will be really light. It also feels somewhat disconnected and loose. It does this at high speeds and low.

Garage had it, but couldn't see anything obvious and stated it could be:

Shock Absorbers
Lower Control Arm
Lower Wishbone

Given this is driving me mad, I am likely going to be throwing money at the problem till it goes away. With that in mind, where would the 'smart money' be to try and get replaced to hopefully resolve this issue? Car is at 91k miles.

This can be steering rack bushing which is normally a cheap fix. If your steering is ok as you start to drive and is getting lighter, wobblier longer you drive (ok at cold ambient temperatures, worse when hot) this is likely to be it. There may also be, but not necessarily, some knocking if that's it.

[TurboWeasel]

Yeah first thing to do is the repair kit if your car has the Thyssenkrup rack, which it should do as I think only very early F3xs had the ZF rack.

It's only 50 quid and DIY able. There is a long drawn out procedure requiring many dealer only specialist tools do it 'properly' but it's doable with trial and error. The tensioning cap can be reached easily from the engine bay without jacking it up on the 30d, not sure about the 20d. So you basically just keep tweaking it until the steering feels tight and slop free, but not to the point where it won't self centre (too tight).

I faffed around with this over many months and got the tensioning cap spot on, but in the end, I discovered the inconsistency and vagueness was all down to the bloody tyres

Had a set of BMW * Pilot Sport 4 Zero Pressure fitted and the steering has been perfect ever since. The previous tyres were the crappy OEM Bridgestone SOO1s, which were 8 years old, so hardly surprising really.

[boxrick]

Originally Posted by Allworth

This can be steering rack bushing which is normally a cheap fix. If your steering is ok as you start to drive and is getting lighter, wobblier longer you drive (ok at cold ambient temperatures, worse when hot) this is likely to be it. There may also be, but not necessarily, some knocking if that's it.

I had all the suspension arms changed over and replaced and spent money on getting a full "geo" tracking done.

It still feels like absolute crap. Also bear in mind I have a few month old Aymsymetric 6 Conti tyres at the correct pressures.

I think the only thing left is a steering rack replacement, what would this usually cost? I did also notice a bit of clunking steering in a car park yesterday.

Could this have anything to do with me not using run flats?