vash68

Hey guys, need your advise on rear wheels alignment, negative camber amount in particular.

So I managed to put 45kmi on my 2009 535xi E61 before I noticed my rear tires were worn on inside shoulders. I have two wheels sets: summer and winter - this prolonged my ignorance. My summer (all season) rears are now chewed up after 22Kmi.


I took my car to a dealer because I thought my air suspension might have malfunctioned, however everything checked out OK, they even did wheel alignment and that came out "as per BMW specs" . When I looked at wheel alignment printout, I wanted to say "idiots!" first:
2 degrees of negative camber on my rear wheels is "normal" for street car? Are you mad? But then I red "Target" column...

Quick search on forums revealed the ugly truth for 1st time BMW owner: THIS IS NORMAL for these cars.

Longer research on BMW forums indicates that some owners agree to replace their tires every 20kmi and continue to pay. While others reduce rear negative camber angle to 1 - 1.2 degree in order to prolong tire life. However, this is a minority and I can't find definitive answer on whether that helped tire wear or adversely affected drivability etc.

I am in camp #2: this is my daily driver and I never track this car and I hate wasting thousands USD on new tires every 20kmi.

Questions:

1. What is the safe compromise for rear camber on E60/E61 cars? I am debating between
1 and 1.2 degree. Will I see my tires last 40kmi if I reduce camber from 2 to 1 degree?

2. In a 'Target' column, which I assume is a spec, for rear camber: why do they have 2"08' for Right wheel and 1"52' for Left wheel? Should't they be the same 2 degree?

3. Should I make any rear toe adjustments at the same time as I reduce camber angle?

Here is my current alignment specs from BMW dealer:

never mind hand written 35psi all around - I ran approx. 35psi front and 41 psi rear, square setup of 18" winter and 19 summer A/S tires.

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Lotus99

I just noticed abnormal wear on the inside of my rears too, though only on passenger side IIRC. Was going to get them aligned as I figured that one was off. As you say, with oem specs, it's often the case that the inside wears too much, esp. if you have run flats, which tend to be worse for that. My summers are currently run flats.

Does seem odd that their target specs for the rear aren't the same. Unless they're trying to compensate for something and the tech intentionally adjusted the target?

I'll see what my shop says as far as what specs they were before and after. I'm getting RD sway bars installed too, so maybe I can give up a bit of neg. camber and not feel deterioration in handling.

Lotus99

As I suspected, my rear passenger camber was off way more than the driver's side, which supports that tire's inside being worn so much more. Had it fixed with a new alignment.
.

vash68

Lotus, how is your tire mileage with stock alignment?

After researching this topic on other forums, I see people reduce rear camber from -2 deg to -1.5 and even -1.3 degree.

I will update this thread once I get my alignment done.

Lotus99

I only have put 7000 km's on the car in the past year, mostly on summers but some on winters too, so mileage is hard to gauge. Interesting that people are going with less than -2. I asked my shop, which is a tuning shop, if I should do that to avoid more inside wear, especially since I've got run flats still (which tend to be worse in that regard), and they still said stick with factory specs, as the extra half a degree of less camber won't mean much difference, and handling would be better with -2. So I left it as is.

But come to think of it, if -2.5 caused premature wear on the inside on one side, it would go to reason that -1.5 would make a difference vs. -2...

vash68

After some research I decided to reduce rear camber from -2.0 to -1.5 degrees.
Since BMW dealers around here would not align out of spec, I ended up getting life time alignment at Firestone. The guy who worked on my car (E61) said that the rear passenger wheel would not align less than -1.5 degree, so this may be the minimum for rear camber adjustment on E60/61 cars.

Cheers