Mercedes SLK World banner

Status
Not open for further replies.
1 - 20 of 44 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter #1
I bought a certified pre owned SLK 350 in August of 2014, it had new tires on it and had just been aligned. Since then, i have replaced the rear tires 3 times and 1 new alignment. 2 sets of Pirelli and one set of Michelins. I have 18 inch wheels. I have put 16K miles on the car in a little over 2 years, and i now need to put a 4th set of rears on ! Fronts are fine. I am 69 years old, i don't drive it hard. Is 5K/set "normal" wear. How many miles are others getting on rear tires ? Other than alignment, what else can be done ?
 

·
Administrator 2009 SLK 55 AMG/Founding Member 2006
Joined
·
98,478 Posts
4 wheel alignment or tire balanced?


I have a 55 AMG so I get about 10000 per rear tire cause I burn a lot of rubber
others? about 20k i would think
 

·
Registered
Joined
·
11 Posts
Discussion Starter #3
I would LOVE to get 10K/ set of rear tires and i do NOT smoke them! The dealership aligns the car on their machine, i assume it is a 4 wheel alignment. I do not know the difference between wheel alignment and tire alignment ?
 

·
Administrator 2009 SLK 55 AMG/Founding Member 2006
Joined
·
98,478 Posts
wheel balancing is where they put the rim and tire in a hooded machine and spin it n put weights on it to balance it

see this video on 4 wheel alignment


tire alignment is 4 wheel alignment :D
 

·
Registered
Joined
·
278 Posts
The tires I just took off my '99 230 had these wear patterns:
RF - looked almost new
LF - about 50%
RR - down to the wear bars and the inner half was worn more then the outer half
LR - close to the wear bars but evenly worn


(This is a project car that I'm still working on. I have no idea how many miles are on the tires. They were on it when I got it. But it was time to replace the tires as it is now running.)
 

·
Registered
Joined
·
11 Posts
Discussion Starter #6
My first 2 set of Pirellis were worn evenly across the tire, just basically bald after 5K miles. This third set of Michelins , after the new alignment ,are mostly worn on the inner treads, i would say negative chamber. I go back to the dealership tomorrow. They are working with me, they paid for the second set of Pirellis, did a free alignment and i paid for the 3rd set of michelins. I really love the car, but this seems crazy.
 

·
Premium Member 2004 SLK32 AMG
Joined
·
5,347 Posts
Be interesting what they find. They too recognize something odd or,they would not have paid for the tires.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #8
Well, after the first set burned through in 5K miles, i convinced them that that was NO way they were new tires when i bought the car, even though their paperwork indicated that they were new.
What else could go wrong with rear tires other than alignment...what else could it be? There is no weight back there and i keep up with tire pressure. I am positive that i am not racing the car ! I have seen tires that were out of balance, the have a distinctive wear pattern and also, you can generally feel the imbalance when you drive. Could it just be a "bad" car?
 

·
Super Moderator 2006 SLK 280
Joined
·
11,316 Posts
5k is definitely not normal. I would have a shop check to make sure something is not causing some kind of binding in the rear wheels. Like an emergency brake partially engaged.
 

·
Registered
Joined
·
352 Posts
I think wear is a little better for highway miles than city miles, just like gas mileage. A tire with an old date code might wear strangely, but they usually get harder. That's if the date is six or seven years old.


The rear Pirelli PZeros on our car aren't quite down to the wear bars yet at 13,000 miles on an SLK250, 101hp less. I expected more like 20K. I know I haven't done any burnouts - my wife says she hasn't either but who knows. :) I'll put on snow tires in a couple of weeks and buy new rears in the spring.
 

·
Founding Member #2 2008 SLK55 AMG
Joined
·
19,407 Posts
...
I have a 55 AMG so I get about 10000 per rear tire .....
I echo the same.... although i don't go Mustang hunting :grin:
 

·
Founding Member #2 2008 SLK55 AMG
Joined
·
19,407 Posts
I bought a certified pre owned SLK 350 in August of 2014, it had new tires on it and had just been aligned. Since then, i have replaced the rear tires 3 times and 1 new alignment. 2 sets of Pirelli and one set of Michelins. I have 18 inch wheels. I have put 16K miles on the car in a little over 2 years, and i now need to put a 4th set of rears on ! Fronts are fine. I am 69 years old, i don't drive it hard. Is 5K/set "normal" wear. How many miles are others getting on rear tires ? Other than alignment, what else can be done ?
Would mind giving us more details about the tires?

What type of Pirelli's? Do you know the tread wear rating?
What type Michelin tires? Pilot Super Sports?
Do you check the cold tire inflation every month? Do you check the tread wear with a tread wear gauge? Measure across all grooves?
 
  • Like
Reactions: LIL DON SLK

·
Registered sold both-> SLK350, SLK '55
Joined
·
996 Posts
Please post a picture or the side of the tyre or write down any numbers it says.
Seems that they either install tyres with the wrong load rating, or that they align the with the right camber but the wrong toe.
Is the tyres surface flat or it looks like it has scratches?
 

·
Premium Member
Joined
·
3,248 Posts
SLKs have negative camber on all wheels.
To have even wear on the rear tires and worn out at 5K miles you have to have excessive toe-in.
If alignment is checked and is within specifications, you have a problem with rear link bushings/bearings; a link bushing/bearing has to allow the wheels to move to additional toe-in under load.
Being a rear wheel drive car, the rears are under load almost all the time.
Jmtcw.
 

·
Registered 2005 SLK55 AMG
Joined
·
1,701 Posts
I bought new tyres today from a specialist and had a long chat with one of the assistants, who happened to be a petrolhead himself. After I'd bought my tyres (which by coincidence turned out to be what he runs on his own car) he reminded me that they wouldn't be covered by the OEM 5 year warranty.'WTF is that? I enquired.
Well, according to his intimate knowledge of Continental/Uniroyal, Michelin and Pirelli, those manufacturers produce 'M' specified tyres which have been tweaked to Mercedes particular suspension set ups, with, allegedly, differing wall stiffness and even non-linear tread depth after quite considerable development testing. At this point I reveal that my fronts always wear the inner side to U/S way before the other 80% of the tread is close to the indicator bars - and that I've had my front geometry and linkages checked several times and never been out of spec. 'There you go then' says the tyre man.

However - 'M' specced tyres are quite a bit more expensive and choices are limited, so for a lot of people it makes more sense to buy a slightly cheaper tyre that they like and bin them a little earlier if the wear is uneven. The additional logic is that the legal limit of 1.6mm (the height of the wear blocks) is not really adequate for complete water clearance and many manufacturers recommend for greater safety in the wet, to dump tyres at 2.5 - 3mm. So pay roughly an additional GBP 40-50 per corner, receive a 5 year warranty against manufacturing defects and hopefully run your boots evenly down to the blocks, or compromise a bit and bin at a safer overall tread depth?

Choices choices - and of course, the dude might have been speaking out of his hiney....
 

·
Registered 2013 SLK55 AMG
Joined
·
714 Posts
Have to agree with the statements above... 5K is not normal and going for the 4th set in 16Kmiles is certainly not in line with what I have seen...

Excessive wear can be multiple things... Tyre pressure, wheel balance, alignment (toe in /out; camber negative / positive), type of roads driven on, speeds, cornering etc... I expect the first three can be sorted fairly easily :)
 

·
Registered 2005 SLK55 AMG
Joined
·
1,701 Posts
My first 2 set of Pirellis were worn evenly across the tire, just basically bald after 5K miles. This third set of Michelins , after the new alignment ,are mostly worn on the inner treads, i would say negative chamber. I go back to the dealership tomorrow. They are working with me, they paid for the second set of Pirellis, did a free alignment and i paid for the 3rd set of michelins. I really love the car, but this seems crazy.

My rears always wear evenly, despite that I run high pressures in an attempt to save my 18'' AMG rims in the case of a pothole or raised drain. So far this has worked, but lost a nearly new 'M' spec P-Zero with a non warranty covered sidewall failure (raised drain). I rarely smoke my tyres, but 'chirp' them at red lights quite a bit. In the wet, I let the ESP sort them out, but I figure there's not too much friction anyway. I drive 75% of the time in 'C' and 25% in 'S', but since I live in the 'burbs, I reset my throttle/tranny 'adaptive' once in a while as the car gets bored with congested roads. I get 9/10k miles from a set of rears.
 

·
Registered 2005 SLK55 AMG
Joined
·
1,701 Posts
Have to agree with the statements above... 5K is not normal and going for the 4th set in 16Kmiles is certainly not in line with what I have seen...

Excessive wear can be multiple things... Tyre pressure, wheel balance, alignment (toe in /out; camber negative / positive), type of roads driven on, speeds, cornering etc... I expect the first three can be sorted fairly easily :)

Pretty much all of these anomalies would result in some form of visible unevenness in wear, such as feathering or tread depth. OP says all looks normal on his worn boots.
 

·
Registered 2005 SLK55 AMG
Joined
·
1,701 Posts
5k is definitely not normal. I would have a shop check to make sure something is not causing some kind of binding in the rear wheels. Like an emergency brake partially engaged.
I think that would more likely smoke the brakes or bearings, rather than the tyres.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #20
The tires that were on the car provided by the dealer were Pirelli P Zero UTQG 220. The fronts are still on the car and look fine, 6-7 32nds. The first rear replacement were with P-Zeros again. After 5K miles they were worn out too, evenly across the tire.
The 3rd replacement, with 4 wheel alignment, i wanted Michelin and a "harder" tire, so i bought Michelin Pilot super sport from tire rack, rears with UTQG of 300. All alignment and installation done at the Mercedes dealership. Now, after 5,600 miles these are almost gone. The tread depth reads 4-5 32nds on the outer groove, 3 32nds in the center groove, ad 2 32nds on the inner groove. This 2 inner grooves are down to the bars.

I don't check the pressure monthly, but i do check them several times / year. I usually run them at the recommended 39 but sometimes at 40. The front are 35 or 36 lbs depending on what i put in the rears.

So, even though the new alignment changed the wear pattern a bit, i am still just getting about 5K -6K miles on the rears ! These tires, since put on in january 2016, were driven 3600 miles with city style driving, and 2000 miles were just put on last week on a road trip to Colorado... speeds generally around 75 +- 20 miles/hour. All this has happened with 16K total miles on the car since i bought it in Aug of 2014. 26K-42K on the odometer.

Thanks all for your ideas.
 

Attachments

1 - 20 of 44 Posts
Status
Not open for further replies.
Top