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Discussion Starter #1
My 2001 SLK320 6 speed is just so powerful. It's like the suspension can't handle the power at highway speeds. I have more confidence in my Subaru Outback. Hitting bumps is almost scary.

How do these cars normally handle on the highway? I was expecting a lot more sturdy and steady. It steers and handles like my Ford Country Squire LTD from college.

I had the tie rods replaced, alignment, wheels balanced, the driveshaft damper replaced, and one set of wheel bearings.

One problem may be the rear suspension. I bought it from a guy who says he replaced the shocks and springs. But he also put wider tires than the factory specs, and it is raised up in the back a little--and maddeningly, more on the left than the right! Looks pretty dumb of you look closely.

So I'd like to correct that for looks if nothing else, but could that be causing my floaty problem? And what exactly would I do to bring this car back to normal? Could I do the work myself?

Thanks!

 

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more on the left than the right

you answered your own question

you also did not mention the correct tire pressure

and how much higher than spec are the rear tires in size?

wheels are supposed to be staggered...are they still staggered? 225 on front and 245 on rear?

you said wheels balanced but you did not say you had a 4 wheel alignment done

put oem correct springs and struts/shocks back on
 

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In addition to @jbanks15 comments, based on the age of the car, possibly higher mileage, and the winter road chemicals, most all of the suspension components are quite possibly ready for full and complete replacement. All bushings, control arm ball joints, springs, struts and shocks, and so on. Since the prior owner(s) left it as you now have found it, then you never know what else they messed up. A front to rear review and replacement plan is likely in order (including make sure the new rear springs are MB parts). Get the car back to how MB delivered as new and you will see the difference from what you have today. Good luck.
 

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Before chasing other parts I'd be looking at undoing the work done by previous owner.

They may have been interested in looks and possibly straight line speed.

We had a 170, 230. It handled sweet down the lanes.
With UK weather and potholes, that is saying something for the standard set up.
 

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a couple things cause the handling to feel less confident.. the first is the steering damper. if it's bad, the front tires feel really grabby.. it will also do this with wider front tires. It will feel like the road is tugging you from one side to the other. the second is the steering box itself, which has some adjustment.. but if it's worn out, it feels like your steering shaft is made of rubber.

also make sure all 4 tires are the same size (in relation to what they are supposed to be)
 

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more on the left than the right

you answered your own question

you also did not mention the correct tire pressure

and how much higher than spec are the rear tires in size?

wheels are supposed to be staggered...are they still staggered? 225 on front and 245 on rear?

you said wheels balanced but you did not say you had a 4 wheel alignment done

put oem correct springs and struts/shocks back on



Jeff are those numbers not for the SLK32 ? My book says 205 front and 225 rear for the plain jane SLK320but you are for sure correct. They should be staggered. This looks horrible.
 

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Zooming in to your pic I read 'Roadstone' on the sidewall.

Cheap Korean tyres .... and you want good handling. Not going to happen. Hard rubber may give long life but you sacrifice grip .... in spadefuls! Soft sidewalls of high profile tyres make them subject to tramlining and tyre geometry change.

Get a set of at least passable tyres in the right size for starters! Kumho, Hankook or similar.

Make sure that the rear suspension work geometry is correct. Raising the back may have been deliberate to give a softer ride but higher c/g and less stiff resistance to roll is going to foul all sorts of things up on the bumps and turns.
 

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Hi,

245s and 225s are for 17" V6 Kompressor set up :wink:

MB says and my n/a V6 Car has fitted:-

225 / 50 x 16 Rears on the Standard V6 Facelift Rims

205 / 55 x 16 Fronts -------------DITTO---------------

Agreed re Chinesium etc Tyres, put them on your shopping trolley or better still bin them !!

When I bought mine it had a mixture of nearly new Tyres, two of which were cheap sh 1 t, the ride home on purchase day, 400 odd miles last December mostly in the dark and torrential rain, when I was getting tired too was interesting to say the least !!

I immediately replaced them with 4 decent tyres, helluva difference.

If your Car has other than standard wheels fitted, make sure the offsets are correct as well, that will make a big difference.

HTH, Cheers Dave
 

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As Dave replied above ( I replied from your 'quote' message) :D
Thanks Dave

Jeff are those numbers not for the SLK32 ? My book says 205 front and 225 rear for the plain jane SLK320 but you are for sure correct. They should be staggered. This looks horrible.
depends on 16 or 17 inch wheels/rims

Tire Size(s)
205/55R16 = 24.9x8.1R16
225/50R16 = 24.9x8.9R16
225/45R17 = 25x8.9R17
245/40R17 = 24.7x9.6R17
 

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Technically, the tyres/wheels don't have to be staggered.
MB Wheel Fitment Guide :nerd:

Good tyres are a must, particularly for RWD cars. Ditch the Korean/Chinese brands as they appear to be made of nylon, will last forever or until you write the car off in a smash.

I'd also be looking at those rear springs, are they seated correctly?
 

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I'm glad you posted that linky, I now have a surplus set of nice MB Wheels 8.5J x 18 ET 35 need a light (paint job) refurb, didn't think they'd be suitable for my R170 but ........................

Brabus used that size Wheel F & R with ......................

225/40 x 18 Front and 245/ 35 x 18 Rear

or

235/40 x 18 Front and 255/35 x 18 Rear

So now I don't need to buy a set of Wheels when the Big Brakes and V8 motor goes in :grin:

I just took those above Wheels off my S55 to replace them with the correct staggered set that I just refurbed last weekend ................

Just Finished Final Clear Coat :-



Out in the Sun for a week to bake :-



Tyres fitted and balanced yesterday 275/40 x 18 Rear and 245/45 x 18 Front :grin:

Cheers Dave
 

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Discussion Starter #13
The back tires are currently 245/50R16 (they're supposed to be 225/50R16 I think), and the front tires are currently 205/55R16 (that's what they're supposed to be I think). And I did get an alignment, but I don't remember anyone specifically saying "4 wheel." What do you think? Thanks again.
 

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The back tires are currently 245/50R16 (they're supposed to be 225/50R16 I think), and the front tires are currently 205/55R16 (that's what they're supposed to be I think). And I did get an alignment, but I don't remember anyone specifically saying "4 wheel." What do you think? Thanks again.
there is a difference between 4 wheel alignment and wheel balancing and just an alignment

head to google/youtube

https://www.shopuslast.com/4-wheel-alignment-explanation/
 

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Discussion Starter #15
I hear you, but "bushings, control arm ball joints, springs, struts and shocks, and so on..." That sounds pricey!
 

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I hear you, but "bushings, control arm ball joints, springs, struts and shocks, and so on..." That sounds pricey!
and a terrible ride is worth how much?
 

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Discussion Starter #17
OK, this is helpful, thanks. What would you say the least expensive all season tires would be instead of these that would improve the situation? The front ones are Michelin. Can they stay?
 

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If you play with the wheels pay particular attention to the lugs.
Not only are different sizes circulating, but a different shape where the seating is too.

Wrong size/shape is not good.
 

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OK, this is helpful, thanks. What would you say the least expensive all season tires would be instead of these that would improve the situation? The front ones are Michelin. Can they stay?
Yes if a) they have absolute minimum 3mm of tread and b) they have some air in them (32lbs psi or thereabouts is the ideal) >:D

You are correct in thinking that 225/50R16 is the recommended size for the rear tyres - refer to the link that I posted earlier, scroll 80% of the way down the page that you are directed to until you get to R170 SLK.
 
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