Tramlining 320d xdrive 2016

[Tyfab14]

Owner of a 320d xdrive touring from 2016. Bought at a dealership few days ago. Always loved the reliability of this car as my partner owned one in 2016.

The car started to “loose” steering power on straight line over 30mph. Checked the steering rack and there is no play on the couplers. At parking I can steer ok, there is no play at all.

I’ve heard that it could be due to “tramlining”. The tyres are Bridgestone Potenza 225/50R17 RFT.

Odometer120k
Full AA report - not a single warning
Full service logbook.

Just wanted confirmation before I spend $$$ on investigating further.

[anonymous-user]

Loose the runflats the car will be nicer.

[E-bmw]

^^^^ Wot 'e said.

Additionally, when you do, don't go for Potenzas.

They were only average 10 years ago when they were first made & haven't improved over time.

[Pica-Pica]

‘Loose’ or ‘lose’ ?
Please clarify.

[Tyfab14]

Loose

As if there is a play when driving straight line.

[340600]

Ditch the runflats and get a proper 4-wheel alignment, it'll be like a different car.

[Locknut]

Before you rush out to buy expensive tyres, check the tyre pressures. If they are pumped too hard it could be a factor in your problem.

[curvature]

I had this on my 318 Touring. After a couple of local garages and tyres companies completely screwed up the wheel alignment I got it into a main dealer and it was perfect afterwards.

I do 20k + miles each year and have never had an issue with runflats. A blowout on the M6 and recently a large pothole that would have destroyed a regular tyre so think carefully before changing.

[RobM77]

Loose steering sounds strange. Tramlining is when the car scampers left and right, following ridges in the road. However, if that is the issue then many problems like this can be solved simply with a different make of tyre. I can't remember what tyres my previous F10 530d M Sport had, but they were noisy at speed and the car tramlined loads. The car also had mismatched tyres from when I bought it, but I put down the issues simply to the daft tyre sizes (huge steamroller things with a tiny sidewall). My new F10 530d M Sport has exactly the same size, but a different make of tyre fitted all round, all in a similar state of wear, and the problems have vanished - the car is quieter at speed and doesn't tramline at all. I'd be wary of getting rid of runflats, especially with 50 section 17s; I ditched RFTs on my 3 series (205/55s) and it was awful - the car bounced around everywhere because the effective spring rate had dropped with no change in damping. I switched back to RFTs and the car was transformed for the better.

[gareth h]

Check tyre pressures, then get the geo checked, and adjusted if it is out, ideally by someone who knows what he’s doing, factory settings aren’t always the optimum set up.
As others have said non RFTs do make a big difference to ride / handling, but it depends what your view is on being stuck by the side of the road with a flat (I’ve had 3 flats and the foam hasn’t fixed any of them).
I’ve always binned the RFTs, but my wife has just bought a 2018 Mini with them which doesn’t ride too bad so maybe they are improving.

[RobM77]

gareth h said:

I’ve always binned the RFTs, but my wife has just bought a 2018 Mini with them which doesn’t ride too bad so maybe they are improving.

There have been huge steps forward in RFTs over the last few years. I forgot to mention that my new car also rides better than the old one.

Yes as you also say, check pressures and geo. I realise this is a real basic of car maintenance, but it's worth mentioning that many people drive to the garage to check tyre pressures, which is utterly ridiculous for two reasons: 1) driving the car warms the tyres up, and the handbook pressures are for cold tyres; 2) garage pressure gauges are notoriously inaccurate. Get a proper gauge and check them on the drive when the car's not been in direct sun, and at the typical temperature you drive at.

[Pica-Pica]

RobM77 said:

gareth h said:

I’ve always binned the RFTs, but my wife has just bought a 2018 Mini with them which doesn’t ride too bad so maybe they are improving.

There have been huge steps forward in RFTs over the last few years. I forgot to mention that my new car also rides better than the old one.

Yes as you also say, check pressures and geo. I realise this is a real basic of car maintenance, but it's worth mentioning that many people drive to the garage to check tyre pressures, which is utterly ridiculous for two reasons: 1) driving the car warms the tyres up, and the handbook pressures are for cold tyres; 2) garage pressure gauges are notoriously inaccurate. Get a proper gauge and check them on the drive when the car's not been in direct sun, and at the typical temperature you drive at.

Agreed. Run flats take a bit of playing to get the optimum tyre pressure, but they do hold their pressure IME. I overfill mine at the garage gauge, then check them next day with a TireTek analogue gauge.

[anonymous-user]

At 120k it could be all sorts of things.