Excessive inside tire wear (front) - The Unofficial BMW M5 Messageboard (m5board.com)

Mtechnik540i · 1st April 2005, 06:25

When we initially purchased the 540i M Sport, we noticed that the front tires had quite a bit of wear on the inside of the each of the front tires. From there we did the obvious things, replaced the cracking strut mounts, control arms/bushings with the 750 upgrade...had it aligned, and then swapped the good S-03s from the back to the front. Well, several weeks later we've noticed the same wear on both of the front tires...

I am starting to wonder if the suspension in the 540i M Sports, which features EDCIII, are equipped with M5 springs...which would explain a lot, considering that they're made to withstand the weight of s38, not a m60...possibly lowering the car, thus creating more negative camber.

Tell me what you guys think, I know most of you are more used to messing with the M5s instead of the 'Americanized M5s'

Any help would be especially appreciated,

yewcorner · 1st April 2005, 10:09

Did you do both upper and lower control arms? Are the track rods OK? What wheels are fitted, are they ET20 for the front and ET20/22 for the rear. Also, when you had it aligned did you have your local BMW dealership do their KDS on it? It is expensive but I have found it to be far better/reliable than any third party alignment tools.

You can find info here: http://www.totalbmwmag.co.uk/HandsOn/TechNov01.PDF

I couldn't attach the file because I have attached it to the 'Leaking EDC' thread sometime ago and the site wouldn't let me attach it again? Must be saving space!

Lets us know what your results are.

Quote:

Originally Posted by Mtechnik540i

When we initially purchased the 540i M Sport, we noticed that the front tires had quite a bit of wear on the inside of the each of the front tires. From there we did the obvious things, replaced the cracking strut mounts, control arms/bushings with the 750 upgrade...had it aligned, and then swapped the good S-03s from the back to the front. Well, several weeks later we've noticed the same wear on both of the front tires...

I am starting to wonder if the suspension in the 540i M Sports, which features EDCIII, are equipped with M5 springs...which would explain a lot, considering that they're made to withstand the weight of s38, not a m60...possibly lowering the car, thus creating more negative camber.

Tell me what you guys think, I know most of you are more used to messing with the M5s instead of the 'Americanized M5s'

Any help would be especially appreciated,

Mtechnik540i · 1st April 2005, 18:01

Quote:

Originally Posted by yewcorner

Did you do both upper and lower control arms? Are the track rods OK? What wheels are fitted, are they ET20 for the front and ET20/22 for the rear. Also, when you had it aligned did you have your local BMW dealership do their KDS on it? It is expensive but I have found it to be far better/reliable than any third party alignment tools.

You can find info here: http://www.totalbmwmag.co.uk/HandsOn/TechNov01.PDF

I couldn't attach the file because I have attached it to the 'Leaking EDC' thread sometime ago and the site wouldn't let me attach it again? Must be saving space!

Lets us know what your results are.

The car rides on it's original 17x8 Turbine IIs...so whatever the offset is on those.

As far as the alignment goes, had it aligned by a very good local place, but didn't take the car to BMW to have 'KDS' performed. Will check on that along with the control arms and track rods.

Donati · 6th April 2005, 18:51

Quote:

Originally Posted by Mtechnik540i

I am starting to wonder if the suspension in the 540i M Sports, which features EDCIII, are equipped with M5 springs...which would explain a lot, considering that they're made to withstand the weight of s38, not a m60...possibly lowering the car, thus creating more negative camber.

I dont think the V8 is heavier than the cast-iron S38.

You can check the camber angle yourself, to see if its within spec.
(take a piece of string, with a weight on it, and messure how far from the upper edge of the rim it is, when it is touching the lower edge of the rim).
Then you will know if camber angle is the cause

My E34 also wears out the inside of the front tires first, but this is because i installed camber ofsetting plates.

Mtechnik540i · 26th April 2005, 04:59

Alright guys, got some alignment numbers for you now after having sway bar links, tie rods, upper/lower control arms, strut hats replaced...
-------------------------------------------------------------------------
**Left/Right

Rear Axle:
-Camber
--Before: -2.05/-2.22
--Target Data: -2.50 +/-0.30
--After: -2.05/-2.20
-Toe
--Total: Before: -0.08 Target Data: 0.21 +/-0.07 After: -0.06
--Left: Before: 0.03 Target Data: 0.11 +/-0.15 After: 0.04
--Right: Before: -0.11 Target Data: ^^^^^^^ After: -0.10
-Geometical Driving Axis: Before: 0.07 Target Data: 0.00 +/-0.15 After: 0.07
--------------------------
Front Axle:
-Camber
--Before: -0.53/-0.50
--Target Data: -0.28 +/-0.30
--After: -1.05/-0.59
-Caster (By way of steering lock)
--Before: 8.12d/7.39d
--Target Data: 8.13 +/-0.30
--After: 7.55d/7.23d
-Track Diff angle
--Right wheel lock 20 degrees Before: -2.12 Target Data: -2.10 +/-0.30 After: -2.12
--Left wheel lock 20 degrees Before: -2.25 Target Data: ^^^^^^ After: -2.04
-Setback
--Before: -0.14
--Target Data: 0.00 +/-0.15
--After: 0.15
-Toe (Unpressed)
--Total: Before: -2.31 Target Data: 0.18 +/-0.05 After: 0.16
--Left: Before: -1.15 Target Data: 0.09 +/-0.03 After: 0.08
--Right: Before: -1.16 Target Data: ^^^^^^^ After: 0.10
----------------------------------------------------------------------

Whew! That took a while. Anyway, that's what they're saying...Only other suspension component I can think of now that could be replaced is having the eccentric bushings pressed in the back...huge deal. $$$$ Is this the correct 'Target Data?'

BTW, had it aligned for the second time now, by BMW this time...they were using a Hunter HTA-MB, but never heard any mention of the KDS that you guys were speaking of. Is this is a problem?

Thanks a million for any help,

Mtechnik540i · 29th April 2005, 00:04

bump