Well I drove down to the local MB dealer today to align my 300E after replacing virtually all front end steering/suspension components and installing new tires.

Tech returned 2 hrs later and told me that I have negative camber in the rear (2+ in) AND in the front (1in) that couldn't be corrected due to incorrect ride height (too low) and he suspected the springs.

The springs were changed 3 years ago but are OE aftermarket (not lowering springs) and when I changed them out I went to a bump lower pad front and back (from 3 to 2 up front and 2 to 1 in rear). I told him this but he still seemed to think the springs were bad or out of spec.

My question(s):

--how bad will neg 2.3 rear camber and neg 1.4 front camber prematurely wear my new set of tires? ($550)

--if I change the spring pads back to spec ... 3 bump front 2 bump rear will that increased ride height significantly improve those camber #'s?

It's interesting to note that after the tech's rear camber adjustment the neg camber actually increased. (albeit small)

Any advice would be greatly appreciated!

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-Paul-
'01 E430, Sport 72,000 mi
'98 C280, 126,500 mi

I doubt that one size different pad with correct that. There are no corrections for camber on your car so he couldn't have adjusted it worse. Its possible a toe correction might change it a small amount.

Unless you have some seriously wild tires you are paying too much. You should click on the Tirerack logo above and check pricing and then find a local authorized tire rack installer to mount them for you. Toe adjustment is probably more important than camber to tire wear but you are likely to loose 25% or more of their life with those rear settings.

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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

Thanks Steve for the help.

Apparently the tech didn't bother to road test because it steers to the right on an even road so I'll have him check the front caster tommorrow.

I'm going to raise the ride height by putting in new MB shims .. however much that improves the neg. camber so be it.

Yeah I went a bit overboard on the tires -- they're Goodyear triple tread from Discount Tire. The only reason I use them over Tire Rack is the free lifetime balance and rotate. It's much more convenient for me since those stores are everywhere here in Houston.

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-Paul-
'01 E430, Sport 72,000 mi
'98 C280, 126,500 mi

I can give you some figures from the W126 as a guide. Might help a bit.

When I started with the ride height on the SDL, the fenderwells were 24.75" from the pavement and the camber (rear) was negative 2.5 degrees. The vehicle was definitely sitting a bit low in the back.

I installed new custom springs that were slightly longer than stock (aftermarket stock springs didn't raise the ride height at all) and the ride height increased to 27". This is a significant change and the vehicle rides a bit high in the back with no fuel or baggage.

The rear camber is now just slightly negative (about 1/4 degree). The spec begins at 1/2 degree, so, a thinner pad would be preferable for it.

So, for the W126, you get about 1 degree of camber change for each one inch change in ride height.

Also, note that there is a multiplication factor for the spring pads. If you change from a 14mm pad to a 19 mm pad, the difference of 5mm is compounded by the leverage in the suspension. In the case of the W126, the ratio is approximately 2.5:1. So the height of the vehicle would change by about 12.5 mm with a pad change of one size. This would equate to about 1/2 degree of camber.

Thanks Brian for the tips. I investigated the rear springs that were installed and discovered that I had the "red" marked shorter spring .. in pic you can see it's about a 1/4 turn shorter than the "blue" spring -- so the dealer was right on the mark. (thank god for my '92 junker 300E). In '90 the 300E's went to the short and long in the rear based on weight, options, etc. Somehow I screwed it up and ordered the red a couple years back when my car calls for blue.


I threw on the longer spring and the 2 nub pad that came off junker was still in good condition so I put it on also (dealer doesn't stock 'em) and the height jumped approx 3/8 inch -- about 10mm. It's definitely noticeable, if not by the pictures. The neg camber seems to be all but gone. Tommorrow I'll do other side and swing by dealer to get it checked again.

Before:


After:


Thanks again fellas.

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-Paul-
'01 E430, Sport 72,000 mi
'98 C280, 126,500 mi

Paul, although an increase in ride height of 3/8" will reduce the negative camber somewhat, it's impossible for this distance to reduce it from 2.3° negative down to zero. However, it might have reduced it sufficiently to get down below 1.5°.........which is probably acceptable.

I'll be curious to see the actual rear camber with the increase in ride height of 3/8".

BTW, you can check your own rear camber with a 24" level with reasonable accuracy (1/2° or so).