New wheels

ells_924

Active Member
Joined
Oct 8, 2017
Messages
31
Reaction score
1
Location
Gloucester
Your Mercedes
clk 320 cdi
hi guys,

now iv looked at the pined post and this one is not covered...

I am looking at some very nice 8J 18inch wheels but would that be ok on my clk 320cdi 07??

my concern is not the rears as they are 8J 17 at present but the fronts?
also what Tyre size would you put on them and will it cause the Tyre pressure sensor any issues?

Thanks guys
 

Wighty

Senior Member
Joined
Aug 4, 2016
Messages
13,435
Reaction score
12,467
Location
Sunny Essex
Your Mercedes
W211/E320cdi/2009 and CLK200k 2009
If you look in the back of the car handbook it will list wheel and tyre sizes which are suitable .
 
OP
E

ells_924

Active Member
Joined
Oct 8, 2017
Messages
31
Reaction score
1
Location
Gloucester
Your Mercedes
clk 320 cdi
  • Thread Starter
  • Thread starter
  • #3
ah but there looks to be nothing for 8J front and back have different profiles too
 

LostKiwi

Senior Member
Joined
Aug 25, 2006
Messages
31,328
Reaction score
21,575
Location
Midlands / Charente-Maritime
Your Mercedes
'93 500SL-32, '01 W210 Estate E240 (RIP), 02 R230 SL500, 04 Smart Roadster Coupe, 11 R350CDi
We need way more info.
What are the current wheels (diameter/width/ET).
What are the current tyres (width/aspect ratio).
Then same for the new ones.

Also... what are the new wheels off (If MB).
 
OP
E

ells_924

Active Member
Joined
Oct 8, 2017
Messages
31
Reaction score
1
Location
Gloucester
Your Mercedes
clk 320 cdi
  • Thread Starter
  • Thread starter
  • #5
ok currents are std mb 17s running 225/45 front and 245/40 rear

new wheels are 18/8j front and rear and are 5/112
 

John Laidlaw

Senior Member
Joined
Nov 15, 2013
Messages
26,373
Reaction score
9,163
Location
Wirral
Your Mercedes
Land Rover Discovery 4
Sorry still need the ET ( the 5/112 is the bolt data) and the tyre dimensions on the new ones
As LK asks if we could know what the new wheels are from it may help.
 

LostKiwi

Senior Member
Joined
Aug 25, 2006
Messages
31,328
Reaction score
21,575
Location
Midlands / Charente-Maritime
Your Mercedes
'93 500SL-32, '01 W210 Estate E240 (RIP), 02 R230 SL500, 04 Smart Roadster Coupe, 11 R350CDi
Ok let me explain (now that I'm on a laptop and not a phone)...

ET is the offset. This is the spacing of the centreline of the wheel from the hub face. A low ET means the wheels are closer to the edge of the car (wheelarches), a high ET means they are closer to the suspension. Some cars (Smarts) have a negative ET butmost are positive.

Width has a bearing on ET when looking at whether things will fit. For example replacing an 8.5" wide rim with a 7.5" wide rim with the same ET will move both sides of the rim 12.5mm further away from both wheel arch and suspension. To keep the outer edge of the wheel in the same place therefore would mean reducing the ET by 12.5" In most cases as you go wider in rim you need to reduce ET in order for the wheel to clear suspension components but for the front this can compromise clearance for the wheel in the wheel arch when on full lock.

Diameter has a bearing on tyres. In general going up an inch in tyre size will mean a reduction in profile.
You are aiming for all four wheels to have the same diameter as the original fitment.
Use a website such a s www.willtheyfit.com to see in a graphical representation what the difference will be between old and new setups. Note this is NOT a definitive guaranteed fit if you go away from existing overall sizes.

Spigot size is the diameter of the protruding centre ring on the hub. This secures the wheel correctly to the hub and must be the same for the wheel and hub.

Pitch circle is the diameter of an imaginary circle inscribed around the centre of the mounting bolts. Pretty much all MBs are 5/112 so 5 bolts on a 12mm diameter circle.

Finally bolts...
Mercedes use a radius headed bolt. Early cars use an M12 bolt with an R12 head. Later cars use an M14 bolt with an R14 head.
You cannot safely use an R12 bolt in a wheel that is designed for an R14 bolt or an R14 bolt in a wheel designed to acept an R12 bolt. This is VERY important! You can get special M12/R14 bolts to allow the use of later wheels on earlier vehicles but you cannot get bots that allow older M12/R12 wheels to be fitted to newer vehicles with M14 threaded bolts.
Aftermarket wheels typically use a 60 degree taper bolt (in M12 or M14 sizes). You CANNOT use M12/R12, M12/R14 or M14/R14 bolts in a wheel designed for 60 degree taper bolts.
Be sure to use the correct bolt for the wheel being fitted.
 

JBell

Senior Member
Joined
Dec 9, 2011
Messages
14,845
Reaction score
7,186
Location
Torquey
Your Mercedes
C350 CDi Estate (GAD Edition)
Ok, on an 18" wheel for a CLK the tyre sizes are:

225/40 R18" Front
255/35 R18" Rear

OEM Wheel sizes are:

7.5Jx18 ET37 Front
8.5Jx18 ET30 Rear

An 8" wide wheel is too narrow for the rear tyre (the max on an 8" wide wheel is a 245 tyre) you need an 8.5 - 9" wide wheel
 
Last edited:
OP
E

ells_924

Active Member
Joined
Oct 8, 2017
Messages
31
Reaction score
1
Location
Gloucester
Your Mercedes
clk 320 cdi
  • Thread Starter
  • Thread starter
  • #12
ok then guys, looking at riches post this is a no go as i need a wider wheel on the back!

oh well back tot he drawing board.....
thanks to all that guided me
 

JBell

Senior Member
Joined
Dec 9, 2011
Messages
14,845
Reaction score
7,186
Location
Torquey
Your Mercedes
C350 CDi Estate (GAD Edition)
ok then guys, looking at riches post this is a no go as i need a wider wheel on the back!

oh well back tot he drawing board.....
thanks to all that guided me

Are you looking at new??? If so you can use an 8" front and 9" rear wheel

So:

8x18" ET35 front
9x18" ET35-40 rear

will fit straight on that car
 

LostKiwi

Senior Member
Joined
Aug 25, 2006
Messages
31,328
Reaction score
21,575
Location
Midlands / Charente-Maritime
Your Mercedes
'93 500SL-32, '01 W210 Estate E240 (RIP), 02 R230 SL500, 04 Smart Roadster Coupe, 11 R350CDi

LostKiwi

Senior Member
Joined
Aug 25, 2006
Messages
31,328
Reaction score
21,575
Location
Midlands / Charente-Maritime
Your Mercedes
'93 500SL-32, '01 W210 Estate E240 (RIP), 02 R230 SL500, 04 Smart Roadster Coupe, 11 R350CDi
Same front and rear. Aside from that pick one (but they must be the same overall diameter front and rear and no wider than 245).
 

Mark A

Senior Member
Joined
Aug 13, 2006
Messages
1,272
Reaction score
344
Location
Aberdeen
Your Mercedes
58 ML-320CDI.
If you are changing from 17” to 18” and keeping the same width, the profile has to reduce. As above use on of the online calculators to work out what you need otherwise your speedo will be out.
 

JBell

Senior Member
Joined
Dec 9, 2011
Messages
14,845
Reaction score
7,186
Location
Torquey
Your Mercedes
C350 CDi Estate (GAD Edition)
Same front and rear. Aside from that pick one (but they must be the same overall diameter front and rear and no wider than 245).

225/40 R18 all round would be perfect
 


AMF Automotive - We are an independent Mercedes-Benz and AMG specialist located in Paddock Wood, Kent, with full Mercedes Diagnostic equipment. We offer a full portfolio of tuning options for AMGs and can cater for all your Mercedes needs.
Tel: 0203 384 4644www.amfmercedes.com/
Top Bottom