Hi Guys,
I have bought Mercedes SL 18 inch wheels for my 2004 clk.
Just tried to put them on my car today and they wont fit
.
Also the bolts i got in the car wont fit as they too long.
The front wheel size - 8.5x18 = ET35
Tyre size - 255/40/18
The rear wheel size - 9.5x18 = ET40
Tyre size - 285/35/18
Please help as I have already sold my old wheels and need new wheel fitted before old one gone.
Thank you
I have bought Mercedes SL 18 inch wheels for my 2004 clk.
Just tried to put them on my car today and they wont fit
.Also the bolts i got in the car wont fit as they too long.
The front wheel size - 8.5x18 = ET35
Tyre size - 255/40/18
The rear wheel size - 9.5x18 = ET40
Tyre size - 285/35/18
Please help as I have already sold my old wheels and need new wheel fitted before old one gone.
Thank you
Member
I do not think you will get those tire sizes to fit. Without knowing if you have a 320 or a 500 I don't know what offset you need to clear the caliper. We need more info. But my gut tells me those wheels will not work on this car.
just found this link. according to this they fill fit with smaller tyres.
https://mbworld.org/forums/clk-class...these-fit.html
https://mbworld.org/forums/clk-class...these-fit.html
Member
Might work with a combination of tires and spacers. Tires 235/40r18 and 255/35r18.
ok thank you. i will try with the smaller tyres may work without spacers 
Thanks guys

Thanks guys
I tried this website to check offset but did not understand. 
anyone please help me with this
my stock wheels front - ET37 rear- ET32-
New wheels Front- ET35 rear - ET40
http://www.1010tires.com/Tools/Wheel...ulator#Results

anyone please help me with this
my stock wheels front - ET37 rear- ET32-
New wheels Front- ET35 rear - ET40
http://www.1010tires.com/Tools/Wheel...ulator#Results
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Be more specific, what do you mean "won't fit"? I bet they will be sticking out given the offsets on the SL/CLS, is that what you mean? If that's the case, spacers won't help and I think you might need new wheels because there's no real fix. OTOH, if it's a problem with brake clearance (doubtful) then spacers would help.
Also- offsets are only part of the fitment picture but you need to consider widths and tire sizes as mentioned above. Your overall tire diameter is probably larger on the SL.
I don't think they will work on a stock CLK, I have them too and the fronts worked fine on my car without spacers but my car is wide body. Most likely you will need new wheels unfortunately… but give us more information and we can try to help.
Also- offsets are only part of the fitment picture but you need to consider widths and tire sizes as mentioned above. Your overall tire diameter is probably larger on the SL.
I don't think they will work on a stock CLK, I have them too and the fronts worked fine on my car without spacers but my car is wide body. Most likely you will need new wheels unfortunately… but give us more information and we can try to help.
Super Member
Can't tell if you mean the inside of the wheel touching the fender liner or the outside of the wheel touching the wheel arch… but guessing you mean the outside of the wheel touching the inside of the wheel arch.
If that's the case then you have a few options.
1. 285 is too wide a tire for the CLK in my opinion so run a narrower tire like a 265 which should fit the 9.5 wheel fine depending on brand.
2. You can add a touch of camber at an alignment shop, or lower your car if you have coilovers (you probably don't). You will sacrifice some tire wear on the inside of the tire so just swap them from left to right to extend life as needed.
3. Try and fit the fronts on the rear just to see how that works. I did that on my CL500 to experiment and ended up trading in the rear wheels at a shop for an extra pair of fronts to run a non staggered setup which was great because I could then rotate all my tires too. I overpaid for the wheels though considering I traded in the rears. If I did it again I would buy a couple of remanufactured fronts and keep the original rears.
4. The other more permanent option is to take the wheels to a machine shop and mill down the back pad of the wheel a few mm if you can maintain brake clearance and inner tire clearance.
I'd probably try them in that order
If that's the case then you have a few options.
1. 285 is too wide a tire for the CLK in my opinion so run a narrower tire like a 265 which should fit the 9.5 wheel fine depending on brand.
2. You can add a touch of camber at an alignment shop, or lower your car if you have coilovers (you probably don't). You will sacrifice some tire wear on the inside of the tire so just swap them from left to right to extend life as needed.
3. Try and fit the fronts on the rear just to see how that works. I did that on my CL500 to experiment and ended up trading in the rear wheels at a shop for an extra pair of fronts to run a non staggered setup which was great because I could then rotate all my tires too. I overpaid for the wheels though considering I traded in the rears. If I did it again I would buy a couple of remanufactured fronts and keep the original rears.
4. The other more permanent option is to take the wheels to a machine shop and mill down the back pad of the wheel a few mm if you can maintain brake clearance and inner tire clearance.
I'd probably try them in that order
ok thank you so much for your reply, its touching the inner side not outside.
so can i go with the 255/40/18 for rear and different size for front?
so can i go with the 255/40/18 for rear and different size for front?
Super Member
Quote:
so can i go with the 255/40/18 for rear and different size for front?
You need to find out what the stock size tires are for CLK's that came with 18" wheels (if any) and see if they are approved for mounting on the wheel width that you want to use them on (check tire rack for all this information).Originally Posted by thusi444
ok thank you so much for your reply, its touching the inner side not outside.so can i go with the 255/40/18 for rear and different size for front?
Tirerack says 225/40/18 front for an 8.5" wheel (but a 235 or 245 may fit the 8.5 width better) and 255/35/18 rear for a 9.5" wheel on a CLK (but a 265 may fit the 9.5 width better). Tire widths will vary by brand so there's no way to see how it fits without test fitting. I like american brand tires because they tend to run wider (BFG, Michelin, Bridgestone) than some others (Falken, Hankook run narrow).
Also, tire rack has the following wheel fitment confirmed, which is similar to yours:
Front 18x8.5
Offset: 32mm (you said your front wheel offset is 35 so 32 is only 3mm more pushed out and will likely work fine as you stated)
Rec. Tire Size:225/40-18 (you said you are using a 255/40/18 tire which is a bit wider than the 225 they suggest so watch for rubbing, especially when turning)
Rear 18x9.5
Offset: 31mm (you said your offset is 40 so you can add a 10mm spacer to achieve a 30mm offset which should be fine)
Rec. Tire Size:255/35-18 (you said you have a 285/35/18 which is again wider and taller so may rub things)
The good news is you don't have to sell the rear wheels because they will fit with a spacer (makes sense why it is touching inside). However you may think about reselling these tires and buying more correct tire sizes and you probably won't have a problem. If you can get away with using the oversize tires just be aware that your speedo may be slightly off a few percentage points in accuracy since the overall diameter is also changed and thus the revolution count. The rear spacer you can get from ebay just make sure it is a hub centric billet aluminum spacer with the correct center bore for this car and the wheels.
Hi,
Thank you very much for you reply.
Front - What i have decide to put 225/40/18 tyres on the front with M12 21mm wheel bolts as orginal M12 bolts are 40mm and too long. only question is apparently SL wheels use M14.
Rear - Use 255/40/18 on the back wheel with 12mm wheel spacers with orginal M12 40mm bolts as it fit perfect.
Is it ok to use M12 instead of M14 they are same tread 1.5mm?
Thank you
Thank you very much for you reply.
Front - What i have decide to put 225/40/18 tyres on the front with M12 21mm wheel bolts as orginal M12 bolts are 40mm and too long. only question is apparently SL wheels use M14.
Rear - Use 255/40/18 on the back wheel with 12mm wheel spacers with orginal M12 40mm bolts as it fit perfect.
Is it ok to use M12 instead of M14 they are same tread 1.5mm?
Thank you
Super Member
I would think you need to use M12. The wheels just have a hole in them so they don't know what bolt you are using- you are threading into the wheel hub itself which is specific to your car and doesn't change even though the SL uses the M14. I'm not positive about using M12 but it seems reasonable to me. M12 is the width of the thread in millimeters. The size of a bolt is normally given by its width (M12) followed by its length (say 35). M12x35 is a 12mm wide thread and is 35mm long (35mm long thread excluding the head, which is the shank length). Make sure you get the correct seat type when you change to new bolts, even if the wheel has a 14mm hole all the force that keeps the wheel locked in is the surface area of the seat so that's critical.
Also, if you use 255/40/18 on the rear your tire will be taller than stock, and thus your speedo will be off as I mentioned. Probably only 2-4% is my guess, but it is on the drive wheels too so you are effectively making your gear ratios a little taller too. And if the traction control is measuring the difference between front and rear it may also work incorrectly or get confused. Just FYI, none of this may be a "problem" as I run taller diameter on 20" wheels but that's both front and rear. If you're going to modify cars you have to live with some compromises anyway.
Also, if you use 255/40/18 on the rear your tire will be taller than stock, and thus your speedo will be off as I mentioned. Probably only 2-4% is my guess, but it is on the drive wheels too so you are effectively making your gear ratios a little taller too. And if the traction control is measuring the difference between front and rear it may also work incorrectly or get confused. Just FYI, none of this may be a "problem" as I run taller diameter on 20" wheels but that's both front and rear. If you're going to modify cars you have to live with some compromises anyway.
ok, I am getting it done tomorrow. will let you know if all ok.
Thank you so much for you all help. much appreciated.
Thank you so much for you all help. much appreciated.

Member
honestly using m12 bolts is dangerous,get custom bolts with 14 mm size seats and 12 mm threaded part.
Member
http://www.benzworld.org/forums/w210...formation.html
read this it may help
read this it may help
Member
You need to go with 255/35r18 on the rear. Not 255/40r18. Post some pics when done!
Hi All,
I have fitted Mercedes SL wheels on my CLK today. They are all fine.
Front - 225/40/18 with M12, 21mm tread length bolts bolts.
Rear - 255/40/18 with 12mm spacers and M12, 40mm bolts which was original CLK 16'inch alloy wheels bolts I had on the car.
Thanks for you guys
Here are some picture
I have fitted Mercedes SL wheels on my CLK today. They are all fine.
Front - 225/40/18 with M12, 21mm tread length bolts bolts.
Rear - 255/40/18 with 12mm spacers and M12, 40mm bolts which was original CLK 16'inch alloy wheels bolts I had on the car.
Thanks for you guys
Here are some picture

If you really want you can get custom made M14 lug seats M12 bolts . its you choice but I have used M12 bolts for now. but will get some proper bolts soon. According to Tyre garage M12 bolts are ok with this wheels.
Thanks
Thanks
Member
if your cruise control does nt work over 60 mph its because you have the wrong size rear tyres,should be 35 profile not 40
