Advice needed. Should I complain ?

[jamesfirefighter]

This is quite long winded, but i've done my best to make it short whilst including all the relevant information. Thanks for reading.

I got my Z4 back from the garage 1 week ago. Before I took it in, it drove fine, no steering problems what so ever.

I wanted to have it lowered (purely for cosmetic purposes) so I supplied Eibach pro lowering springs and had them fitted all round (approx 25-30mm Drop, as it was previously on M/sport springs).

I also wanted all the bushes replacing, as I had noticed a few clunks going over potholes when driving. Instead of buying just the bushes, I thought it'd work out slightly cheaper to buy whole new front wishbone assembles with uprated MEYLE HD bushes in them. I bought these over OEM parts as these have had good reviews on here and they have a 4 year warranty:
http://www.ebay.co.uk/itm/BMW-Z4-E85-E86-CONTROL-ARMS-WISHBONE-BUSH-MEYLE-HD-C813-/190933378791?ssPageName=ADME:L:OC:GB:3160

I also bought these MEYLE front anti roll drop links :
http://www.ebay.co.uk/itm/BMW-2-Heavy-Duty-FRONT-Antiroll-Bar-Stabiliser-Drop-Link-Links-Meyle-HD-PAIR-/121241947737?ssPageName=ADME:L:OC:GB:3160

On the rear, I bought new rear trailing arm bushes : http://www.ebay.co.uk/itm/2-BMW-3-SERIES-E36-E46-REAR-TRAILING-SUSPENSION-ARM-BUSH-HEAVY-DUTY-MEYLE-HD-NEW-/131053772637?ssPageName=ADME:L:OC:GB:3160

Lastly, whilst it was in the garage I thought i'd may as well get the Advisories from previous MOT sorted too. So I had all new tyres fitted (Goodyear Eagle F1 Asymmetric (Rears are 255/35/18 XL on, Fronts are 225/40/18 XL on 224 M sport wheels.

Once all these parts were fitted, the car was taken to a specialist 4 wheel alignment centre to get the geometry sorted.

When I collected the car, it just didn't look right. I thought this was due to the new 'stance' as a result of the lowering. However, after driving it I knew something wasn't right at all. After some head scratching and on a closer inspection I came to realise that the fitter at the garage had put the rear wheels on the front (with the 225 profile tyre) and the front wheels on the rear (with the 255 profile tyre). Tyre pressures are 34 rear, 32 front.

I took my car back to the garage and explained. Needless to say, the boss was mortified and in sheer embarrassment of what they'd done. He said he'd put it right, but I said no and asked him instead to cover the cost of taking it to my local tyre fitter to get it all swapped over, as well as the cost to get it realigned with the wheels on the correct axels.

On an initial test drive I couldn't have been happier. It felt fine. However yesterday, I had a day off and since It was nice and dry, I took the car out for a long drive and drove it at speed on some twisty roads that I like.

Between 40-110mph the car feels very unstable, it tramlines terribly (which it never did before) and I really have to hold on tight to keep it in a straight line as the steering wheel wants to go to the left and the right (almost feels like i'm fighting the power steering due to the resistance and feedback that I can feel. Same in Sports mode. The steering wheel also banks left and right under heavy breaking. Needless to say, its no longer fun to drive at speed.

I don't know if this change is due to a component fault, due to an error in the fitting perhaps, or just because of the characteristics of the new non OEM parts I have had fitted.

I think I should take it back to the original garage, but I'm not really sure how to approach them.

I'm just gutted that I paid about £1500 for the parts and labour, and the car is now worse off Kinda wish i'd left it alone.

Any advice / suggestions? Many thanks, James

 

[Montjeu]

If I was you I'd take it to someone highly recommended (ideally independent bmw specialist) who knows what they are doing to give your suspension set up a once over and probably a test drive. Aside from fitting the parts there's not much to do of course now you've got the tyres corrected. Firstly triple check all your parts were suitable for your exact vehicle. Can you upload your final Hunter settings?

 

[Eviltad]

Are the right tyres on the right width of wheel? IF they got the rear and fronts mixed up they could also have done the same when fitting, although I'm not sure how much influence this would have on handling.

 

[Zeld4]

Can I ask if you took it to the wheel alignment specialist or did the garage sort it? If they took it to the specialist I find it hard to believe that also they wouldn't have noticed the problem. If they did miss it then they can hardly be specialists.

With the tramlining it could be tyre pressures. i found when moving to non runflats just a few pounds makes a huge difference. I eventually settles on 34 front and 37 rear psi. lots of people on here seem to recommend low pressures to improve ride quality but I think it ruins the handling. Maybe try upping the pressures to what BMW recommend first. Good luck.

 

[jamesfirefighter]

Are the right tyres on the right width of wheel? IF they got the rear and fronts mixed up they could also have done the same when fitting, although I'm not sure how much influence this would have on handling.

yes the correct tyres are on the correct wheels now.

 

[jamesfirefighter]

If I was you I'd take it to someone highly recommended (ideally independent bmw specialist) who knows what they are doing to give your suspension set up a once over and probably a test drive. Aside from fitting the parts there's not much to do of course now you've got the tyres corrected. Firstly triple check all your parts were suitable for your exact vehicle. Can you upload your final Hunter settings?

Thanks for the advice.
Parts are def suitable for my make and model of Z4.
Here is my geometry graph: says Z4m roadster, when its not an //M though. Could this be why?

 

[Montjeu]

I've seen some on here with m sport suspension have it titled m roadster so that may be ok. Mine doesn't,
it reads Sport Suspension (with lower ride height) : 18 Wheel. There's a big difference in your left and right front and rear camber, and my rear camber is -2.5. Might be good if one of the suspension specialists on here take a peak of your settings.