P13TR0

I have an annoying drift to the left. It came about a while ago, but following numerous geometry chacks, I put it down to the new PS2 tyres, and resigned myself to the fact it wouldn't go away until they are changed. Having read another thread here about front suspension springs and trim height, I decided to measure my trim heights. The results. NSF - 365mm OSF - 352mm NSR - 340mm OSR - 340mm The car (BMW coupe) has about a quarter of a tank of fuel on board. Would the front measurements be considered to be within normal tolerance or is this the cause of my drift? Thanks in advance.

Yes the steering is central, although there is a little play between 12 and 11 o'clock. The car has dynamic stability control which monitors a load of things to keep the car going in a straight line. What are you thinking?

Totally agree with that. Tread wear was really bad too! These MPS are giving unbelieveable amounts of grip, and you can feel exactly the point when they are about to break away. Wish I could get this strange loose/ light/ vague steering problem sorted out though. I think it could be the control arm bushes (common problem) but also wondering if one or more wheels was not properly balanced when the MPS were put on. Other strange thing I have noticed is that the pilot sports have 1mm less tread depth on the inner tread groove than on the rest of the tyre. I assume this is by design, as all 4 tyres are brand new and have the same characteristic.

RE040 factory fitment

Hi, I had Bridgestone Potenza's on ther previously. Michelin Pilot Sport 2's are OEM fitment, and I know many people who run them on 330 coupe's without problems like mine. I checked rear springs after seeing the M3 thread. They are fine. My Tyre pressures are spot on 38 psi front and 44 rear as per door pilar and Michelin spec. I think it is eaither the toe angle or the front control arm bushes??? Thanks for your replies

Hi Tony... I'm Back I had 4 new Pilot Sport 2's put on the car this weekend, and since then I have had the following problem. (This problem may have been there for several weeks, but could have been disguised by the nsf -ve camber wear on my old set of tyres which was causing increased tramlining). The car feels great on country roads, but I got on the motorway for a long run, and at what appears to be random times, the steering goes light and vague. This is not tramlining as I know it!! I have had the car from new and covered almost 30K miles so I know it used to feel a lot more planted than it does now at speed. The thing I dont understand is that one minute it's fine and the next its all light and fluffy. Its almost like the dead zone of the steering input increases for a moment and im on a patch of ice. Things I have considered: 1) Warped wheel 2) One or more wheels not balanced properly 3) Worn suspension parts - shocks, bushes etc... 4) Reduced front toe angle (during the laser alignment I had done 3k miles ago the guy changed my toe angle from 11 minutes to 0.05 minutes - which is still within BMW spec for my car) Anyone have any ideas? This is driving me crazy..... thanks in advance.

Just spoke to the operator that carried out my geometry. It turns out that there is an option on the Beissbarth system to either perform the alignment with the car loaded as BMW state, or another option to align the car by entering the ride height without having to load up the car. They chose the ride heigth method. The guy I spoke to didn't seem to think that the fuel tank being half empty would be the cause in the caster being off. It is noteable that the caster was out of spec before and after alignment when compared with the target data.

So does that mean that if my car was not loaded as specified by the manufacturer, the above alignment is worthless? Thanks

Thanks Tony. I ran the car for several thousand miles after the pot hole, and it was the change in tyre wear that prompted the geometry check. It wasnt a big hit, so I thought things were ok. I didn't notice any change in handling, but I am much more aware of the effects of poor geometry having spent some time looking around here.... I won't make the same mistake again, especially considering the cost of a new set of 4 tyres...... ouch. I still have one remaining question. The uneaven wear will mean that the tyre wasn't sat flat on the scissor lift. As the wear increased towards the inside shoulder by about 2mm, I assume that this could have lead to the initial camber measurement showing more -ve than it actually was? This in turn will have lead to an over adjustment of camber, so that when I put new tyres on, and they sit perfectly flat, my camber will be out of spec again? Or.... am I completely wrong, and the tyre wear will not effect any of the measurements... Thanks..... I have learnt a lot in the past few days...

Thanks Tony and Dan. I am not sure if the car was loaded during the alignment. I will check with the guys that did the work. If it turns out it wasn't loaded, would that render the current alignment useless, and mean I need to re-align? One other question I have is: The NSF had about 2mm more wear on the inside shoulder when the alignment was carried out. Will the fact that the tyre had an uneaven wear have increased the -ve camber reading, thus meaning that when I put on a new set of tyres, the new camber position will be incorrect. Thanks

Hi Tony.... This was a few weeks ago now, but I would say there was between half and 3/4 of a tank of fuel in the car. I gather from reading other posts that the car should have been tanked, and loaded when performing the geometry. What annoys me is that the technician didn't tell me any of that, but still charged me £85 for what could have been a poor alignment. If there is likely to be any problems with my current set-up, I will go back and negotiate a re-alignment with them under proper conditions. My local BMW dealer charges nearly £200 for what they call a KDS, and I have my doubts as to whether they would ensure the car was fueld and loaded. I wish there were more professionals who take the care and attention over alignment that you obviously do. Thanks

Hello from a noobie I have a 330cd coupe and a few questions regarding geometry and tyre wear. I hit a pot hole, so decided to get a 4 wheel alignment. It turned out my NSF had to much -ve camber. This manifested itself in slightly increased tyre wear on the inner shoulder. Below is the alignment print out: I have a few questions. 1) The castor after alignment is more on the right side, whereas it was much more symmetrical before alignment. Is this normal/ what effect would this have? 2) I have a little play between 12.00 and 11.00 on the steering wheel at high speed, is this due to the castor? 3) The operator reduced my toe on the front, what effect will this have? 4) Realisticly would the before NSF camber have caused more tyre wear? 5) The car had never been aligned before, and is 18 months old.... why would the castor have been out of BMW spec from the factory? 6) Is it normal to have the following wear patterns on 18" low profile tyres: - OSF - increased wear outside shoulder (scrubbing of shoulder tread patern - NSF - increased wear on inner shoulder (similar scrubbing of tread pattern to OSF) 7) Was the car subjected to a four wheel alignment (as per my invoice) or a full geometry check? 8) Could there be operator error using the Beissbarth aligner in terms of setting the steering wheel dead straight, or would an error in aligning the steering wheel be obvious via the system. I am paranoid tht I am steering slightly left most of the time. Sorry for asking so many questions. I have read the excellent info on this site, but don't have the knowledge to relate what I read to my questions above. For example, I dont know how noticeable what looks like a small change in toe would be when translated to handling characteristics. Any help is much appreciated...... thanks in advance