I felt some vibrations on high speed (120-140 KMH) so I went to the tire store to balance my wheels. The technician there told me that based on the tire wear, I needed an alignment. Thisis OK because I plan for an alignment after I change the rear shock absorbers next week.

He then told me that the tires should be in good condition for a proper alignment. Any truth in this? I asked because I will need a new tire on my rear-right in 2-3 months.

 

I suspect that if your alignment comes with any kind of "warranty" it will be void if you put new tires on afterwards.
Of course they should also be changed in pairs.

 

One of the guru types can give you a more accurate reply but I thought the "alignment" would align the stuff your wheels attach to. Those adjustment should remain intact. I wouldn't think uneven wear would take the car out of alignment.

The ride is a different issue as the tires would be fighting the alignment.

In any case I would just wait until I replaced the rears and the shocks.

 

I call

 

“I need an alignment” – keep in mind…

Since the mid 90 model’s, there has been no Camber and Caster adjustment facility fitted OEM!

Only current adjustment is front and rear Toe.

To attempt to return vehicle to factory specs to resolve premature inner edge tire wear, improve traction, and fix steering pull the only alternative for Camber and Caster is to fit offset, slotted bolts. But these are inaccurate one only position bolts with a minuscule .3 of one degree adjustment (3mm).

It’s no wonder many owners continually change tire brands or go from one MB Dealer or alignment shop to another trying to get it right/fix the problem.

We saw the need therefore "to fix it right the first time" by designing, developing, patenting (and re-instating from the 1990's) fully adjustable front suspension for virtually all models.

The current K-MAC kits have up to 4 times the adjustment of the one position offset bolts (both Positive or Negative). And unlike these offset one position bolts they can be accurately adjusted - under load, direct on alignment turntable (no need to remove and reinstall each time).

Ongoing precise adjustment of both Camber and Caster settings if altering suspension height, fitting wide profile tires/wheels or for curb knock damage with the unique K-MAC patented design is just a single wrench/no disassembly.

For the rear, similar kits for precise Camber adjustment with additional Toe to compensate for the new Camber facility. Unlike the alternative adjustable Camber arms K-MAC rear kits do not move top of tire outwards - this reducing all important clearance to outer fender when adjusting to fix premature inner edge tire wear/improve rear traction.

Bonus with the four front and four rear bushes is that they are designed with twice the load bearing area and also replace the highest wearing suspension bushings. And with K-MAC no special tools are required to fit.

 

I will change the rear shocks and then do a alignment.

As for the worn tire, I will wait until it is worn down and replace it. This tire should last another few months.

I know, ideally, both tires in each axle should be replaced in pair. However, my rear-right always worn down a lot faster than rear-left. I remember someone said that this is because the rear-right spins more than the rear-left because of the traction control.

 

Unless you have directional tires, you should be able to do a side-to-side "rotation" of both the front and rear tires every few thousand miles. It may help even out the wear of the tires a bit.

 

Any truth to the rear-right wears faster than rear-left? I was told that the traction control always uses the rear-right to test the road surface.

This is the behavior of my w209 based on 10 years of ownership but I never could confirm the reason.

 

It looks like my right tires wear more than my left too.

 

Just to update my tire situation.

I changed the rear shocks and did an alignment afterward. Then 3 days later, I had a flat in the front-right so I went to the same tire store right away. This time I saw it myself, the inside edge (near the side wall) was badly worn, almost to the wire. There was a cut there, I guess it was worn so thin that any small sharp rock would cut it.

I changed to a new tire and went to alignment again. Surprisingly, there was no change in the settings. The guy did not charge me and he actually apologized that he should have checked the tires in my first visit.

I think this front-right tire was worn so drastic because of the broken suspension coil on the front-left a few weeks prior. Not sure how long I drove on the broken coil and it would cause the car to be "tilted".

 

What is your suspension? I'm gonna get Eibach springs with Bilstein Sport shocks with Michelin Pilot Super Sport tires soon and was wondering if I would need a camber kit. I know I need an alignment for sure though.