18" AMG wheels eating tires
#1
Thread Starter
Super Member
Joined: Nov 2012
Posts: 692
Likes: 62
From: Boston Area
2021 Mojave Silver E450, BRG Jaguar F-pace S, 2011 335d (RIP), 2010 E350 (sold)
18" AMG wheels eating tires
I helped a close friend buy a 2011 E550 a year ago and she absolutely loves the car. She was a BMW lover until she sat in this magnificent machine. However, since then she just managed to go blow out her 7th tire. That's right, seven in just under a year. She is a good driver, but the thing is, she is not very careful when it comes to looking for pot holes, and these New England roads don't appear to mix well with that. I have been telling her about how to fix this, but I don't think it will help, so the question is what can we do about this?
My initial recommendation was to put a set of 17" wheels on and be done with it. However, can you put 17s on an E550? Does anyone know if they will clear the brakes?
Another thought would be higher profile and perhaps softer tires than the ContiPros that she has been putting on. Any recommendations there? It is a 4matic so there is plenty of room but it does also have Airmatic.
Any other thoughts? Are there any after market wheels that won't lead to the same issue? I would appreciate any and all opinions.
Thanks.
My initial recommendation was to put a set of 17" wheels on and be done with it. However, can you put 17s on an E550? Does anyone know if they will clear the brakes?
Another thought would be higher profile and perhaps softer tires than the ContiPros that she has been putting on. Any recommendations there? It is a 4matic so there is plenty of room but it does also have Airmatic.
Any other thoughts? Are there any after market wheels that won't lead to the same issue? I would appreciate any and all opinions.
Thanks.
#2
To investigate this fully and offer a fact-based reasoned opinion we need more detail. Please post a few pics of your friend.
But seriously, check with your local MB dealer to make sure 17's will fit.
But seriously, check with your local MB dealer to make sure 17's will fit.
Last edited by noka; 11-28-2014 at 12:11 AM.
#3
I checked tirerack.com and they offer both a 17" winter tire set and 18" set for 2011 E550 4M. However, the Mercedes-Benz Canadian website, www.mbwheels.ca offers only 18" winter sets for E550.
My E250BT4M has the larger front sport brakes; my 17" winter set clears the brake rotors. Your friend should double check with the nearest MB dealer parts department to be sure that 17s would fit the E550. The front rotors might be even larger diameter than the ones on my E250BT.
Obviously, for the pot-holed roads in your area, the 17s would make more sense IF they would fit over the front brakes.
My E250BT4M has the larger front sport brakes; my 17" winter set clears the brake rotors. Your friend should double check with the nearest MB dealer parts department to be sure that 17s would fit the E550. The front rotors might be even larger diameter than the ones on my E250BT.
Obviously, for the pot-holed roads in your area, the 17s would make more sense IF they would fit over the front brakes.
Last edited by DerekACS; 11-27-2014 at 08:45 PM.
#4
After pot-holing and bending all four wheels on our E3504MATIC Sport (W211), we switched to 17" wheels/tires and the change in the car was very significant. It almost feels as if the car was originally calibrated for 17s, and 18s were later added to help create a reasonable Sport package as a quasi-unnatural act. The car is much more comfortable, still steers/handles very well with the Michelin AS3 tires, is quieter, smoother, and no more bent wheels! And, with some good-looking 17s from powerwheelspro.com, the appearance is still very pleasing! I would think this would apply to newer models as well, but brake caliper clearance should be confirmed.
#5
MBWorld Fanatic!
Joined: Oct 2010
Posts: 4,552
Likes: 942
From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
17" should fit fine. All info I have found speaks for this. MB also sells 17" wheels for these cars.
My car is an E550 without 4-Matic so I have the staggered setup but I am going to sacrifice that to be able to go with 17" wheels all around. My concern was if the brakes are bigger on the E550 compared to E350 but they are not. MB parts guy said they take the same brake pads too. AMG is where the brakes are bigger and 7" wheel will not fit.
Tire size 245/45-R17. It is 0.9 mm smaller in diameter than the OEM 245/40-R18 meaning speed difference is minimal.
My car is an E550 without 4-Matic so I have the staggered setup but I am going to sacrifice that to be able to go with 17" wheels all around. My concern was if the brakes are bigger on the E550 compared to E350 but they are not. MB parts guy said they take the same brake pads too. AMG is where the brakes are bigger and 7" wheel will not fit.
Tire size 245/45-R17. It is 0.9 mm smaller in diameter than the OEM 245/40-R18 meaning speed difference is minimal.
#6
I'm thinking one or more of my 18 amgs might be bent. I have changed tires and rebalanced several times and can't fix a vibration at highway speed. I'm going to have mb check out the suspension next week but if nothing is wrong I think I'll look at doing new wheels. Anyone have more recommendations on websites or places to buy more stock style 17 or 18s similar to what sportstick posted?
Last edited by aeroconfigs; 11-28-2014 at 02:22 PM.
#7
I'm thinking one or more of my 18 amgs might be bent. I have changed tires and rebalanced several times and can't fix a vibration at highway speed. I'm going to have mb check out the suspension next week but if nothing is wrong I think I'll look at doing new wheels. Anyone have more recommendations on websites or places to buy more stock style 17 or 18s similar to what sportstick posted?
Excellent quality and service. although inventory and style vary over time.
Last edited by Sportstick; 11-28-2014 at 03:50 PM.
Trending Topics
#8
Thread Starter
Super Member
Joined: Nov 2012
Posts: 692
Likes: 62
From: Boston Area
2021 Mojave Silver E450, BRG Jaguar F-pace S, 2011 335d (RIP), 2010 E350 (sold)
Thanks everyone, I am looking into the 17" wheels first. I was just a bit concerned because remember reading somewhere that they won't fit over the brakes. Probably a set of reps will do fine for her because for some reason no-one is selling their OEM 17s over on the wheels n tires section. Sort of odd if you ask me, I would think that there would be plenty of people upgrading considering all of the adds we see for 19 and 20 inchers out there. If anyone knows someone with a set of 17" take-offs sitting around send them my way.
My friend who is actually a close family friend and is in fact one of my mothers best friends will be appreciative. From this, I don't think pictures would be as impact-full as some might think. Although the one with my mother and her in a nice SL500 probably would fit well with this forum.
My friend who is actually a close family friend and is in fact one of my mothers best friends will be appreciative. From this, I don't think pictures would be as impact-full as some might think. Although the one with my mother and her in a nice SL500 probably would fit well with this forum.
#9
...My friend who is actually a close family friend and is in fact one of my mothers best friends will be appreciative. From this, I don't think pictures would be as impact-full as some might think. Although the one with my mother and her in a nice SL500 probably would fit well with this forum.
Check with your local MB dealer. Maybe they could be competitive on parts prices (at least my BMW dealer was, although I got an additional BMWCCA discount on top). Maybe MB sales would run into a customer purchasing a vehicle who wants to also swap wheels and has ones that you might be interested in. Put some feelers out there and see what happens. I guess it also depends on timing and how soon your friend needs them.
Last edited by noka; 11-29-2014 at 11:10 AM.
#10
17 Wheels
I helped a close friend buy a 2011 E550 a year ago and she absolutely loves the car. She was a BMW lover until she sat in this magnificent machine. However, since then she just managed to go blow out her 7th tire. That's right, seven in just under a year. She is a good driver, but the thing is, she is not very careful when it comes to looking for pot holes, and these New England roads don't appear to mix well with that. I have been telling her about how to fix this, but I don't think it will help, so the question is what can we do about this?
My initial recommendation was to put a set of 17" wheels on and be done with it. However, can you put 17s on an E550? Does anyone know if they will clear the brakes?
Another thought would be higher profile and perhaps softer tires than the ContiPros that she has been putting on. Any recommendations there? It is a 4matic so there is plenty of room but it does also have Airmatic.
Any other thoughts? Are there any after market wheels that won't lead to the same issue? I would appreciate any and all opinions.
Thanks.
My initial recommendation was to put a set of 17" wheels on and be done with it. However, can you put 17s on an E550? Does anyone know if they will clear the brakes?
Another thought would be higher profile and perhaps softer tires than the ContiPros that she has been putting on. Any recommendations there? It is a 4matic so there is plenty of room but it does also have Airmatic.
Any other thoughts? Are there any after market wheels that won't lead to the same issue? I would appreciate any and all opinions.
Thanks.
There is nothing to be done about someone who smacks potholes at speed because the tire is not expected to take that repeatedly regardless of the car. Another concern is the wheel itself. Repeated blows will lead to cracks and rim failure. Having had a steel rim fail under the bead on a corner in a Volvo years ago this is not something she would like to experience.
I would go for the 17s but she has to slow down or pay more attention regardless whether she drive a Benz or a Bimmer!
#11
Thread Starter
Super Member
Joined: Nov 2012
Posts: 692
Likes: 62
From: Boston Area
2021 Mojave Silver E450, BRG Jaguar F-pace S, 2011 335d (RIP), 2010 E350 (sold)
I hope you realize that I was only joking, as distasteful and juvenile as it appeared to be
Check with your local MB dealer. Maybe they could be competitive on parts prices (at least my BMW dealer was, although I got an additional BMWCCA discount on top). Maybe MB sales would run into a customer purchasing a vehicle who wants to also swap wheels and has ones that you might be interested in. Put some feelers out there and see what happens. I guess it also depends on timing and how soon your friend needs them.
Check with your local MB dealer. Maybe they could be competitive on parts prices (at least my BMW dealer was, although I got an additional BMWCCA discount on top). Maybe MB sales would run into a customer purchasing a vehicle who wants to also swap wheels and has ones that you might be interested in. Put some feelers out there and see what happens. I guess it also depends on timing and how soon your friend needs them.
Pretty good idea about the dealer, not expecting anything reasonable, but worth checking.
#13
Wheels
Lots of wheels in 17: with the right width and offset out there. You can actually get very stylish for not all that much money when compared to OEM wheels. eBay is a source of OEM but I resist unless it is a reputable dealer because you cannot inspect them for rash and cracks.
#14
Thanks everyone, I am looking into the 17" wheels first. I was just a bit concerned because remember reading somewhere that they won't fit over the brakes. Probably a set of reps will do fine for her because for some reason no-one is selling their OEM 17s over on the wheels n tires section.
Be careful ! Every wheel design has a slightly different configuration. Check with a reliable source like www.Tirerack.com before you commit.
#15
Wheels and Tires
Just because a set of OEM 17s might fit does not mean that 17" reps will fit !
Be careful ! Every wheel design has a slightly different configuration. Check with a reliable source like www.Tirerack.com before you commit.
Be careful ! Every wheel design has a slightly different configuration. Check with a reliable source like www.Tirerack.com before you commit.
I had a guy drive me nuts even when I, my dealer parts guy and his dealer parts guy assured him my winters off my W211 would fit his W211 Bluetec. He even refused to believe his manual and was totally surprised when we bolted them on they fit!
Read the manual.
In these discussions offsets get lost and it is important to get that right.
Whereas I have the 2011 E series owner's manual I looked it up.
Page 376 for both axles (BA) covering all US version E350 versions and all US E550 versions including 4Matic in R17 is listed as 8.0J x 17 H2 48 mm offset with a 245/45 R17 95H or 99V Tire as primary option.
Secondary option is 8.5J x 17 R17 H2 48 mm offset with the same tire as above.
Winters are the same wheel with a 245/45 R17 99 V XL winter tire.
My summer wheels are 8.5J x 18 H2 48 mm positive offset with 245/40 R18 97 V tires. My winter wheels are 8.5 J x 17 H2 with a 45 mm positive offset and they are fine.
3 mm less offset is fine. More offset could be problematic as it sets the hub back in the wheel well.
My after market rims cost about $110 each.
A 17" wheel 8.0-8.5 inches wide with a 45-48 mm positive offset will be just fine on this 2011 E550 in question.
End of grump. Have a great day!
Last edited by Alex.currie44; 11-30-2014 at 12:43 AM.
#16
MBWorld Fanatic!
Joined: Oct 2010
Posts: 4,552
Likes: 942
From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
I am going to sound grumpy here and that is not my intent but one of the things on this site, Benzworld and the SLK Forum that drives me crazy is the opinions and WAGs expressed about fitment of wheels and tires when the answer is in the owners manual or the dealer. Manuals are available on line as well.
I had a guy drive me nuts even when I, my dealer parts guy and his dealer parts guy assured him my winters off my W211 would fit his W211 Bluetec. He even refused to believe his manual and was totally surprised when we bolted them on they fit!
Read the manual.
In these discussions offsets get lost and it is important to get that right.
Whereas I have the 2011 E series owner's manual I looked it up.
Page 376 for both axles (BA) covering all US version E350 versions and all US E550 versions including 4Matic in R17 is listed as 8.0J x 17 H2 48 mm offset with a 245/45 R17 95H or 99V Tire as primary option.
Secondary option is 8.5J x 17 R17 H2 48 mm offset with the same tire as above.
Winters are the same wheel with a 245/45 R17 99 V XL winter tire.
My summer wheels are 8.5J x 18 H2 48 mm positive offset with 245/40 R18 97 V tires. My winter wheels are 8.5 J x 17 H2 with a 45 mm positive offset and they are fine.
3 mm less offset is fine. More offset could be problematic as it sets the hub back in the wheel well.
My after market rims cost about $110 each.
A 17" wheel 8.0-8.5 inches wide with a 45-48 mm positive offset will be just fine on this 2011 E550 in question.
End of grump. Have a great day!
I had a guy drive me nuts even when I, my dealer parts guy and his dealer parts guy assured him my winters off my W211 would fit his W211 Bluetec. He even refused to believe his manual and was totally surprised when we bolted them on they fit!
Read the manual.
In these discussions offsets get lost and it is important to get that right.
Whereas I have the 2011 E series owner's manual I looked it up.
Page 376 for both axles (BA) covering all US version E350 versions and all US E550 versions including 4Matic in R17 is listed as 8.0J x 17 H2 48 mm offset with a 245/45 R17 95H or 99V Tire as primary option.
Secondary option is 8.5J x 17 R17 H2 48 mm offset with the same tire as above.
Winters are the same wheel with a 245/45 R17 99 V XL winter tire.
My summer wheels are 8.5J x 18 H2 48 mm positive offset with 245/40 R18 97 V tires. My winter wheels are 8.5 J x 17 H2 with a 45 mm positive offset and they are fine.
3 mm less offset is fine. More offset could be problematic as it sets the hub back in the wheel well.
My after market rims cost about $110 each.
A 17" wheel 8.0-8.5 inches wide with a 45-48 mm positive offset will be just fine on this 2011 E550 in question.
End of grump. Have a great day!
In my 2010 E550 manual for the 17" wheels it says:
E350 Luxury, E350 Luxury BlueTec and E550 Luxury - 8.0 J x 17 H2, offset 48 mm.
E350 Sport BlueTec - 8.5 J x 17 H2, offset 48 mm.
The wheel width is 0.5 inches wider with the sports model. I guess they enhance the sports look by using 0.5" wider rim with the same 48 mm offset, which pushes the outer edge of the wheel out by 6.35 mm (1/4").
What is important for anybody thinking of going with different size wheels is to know what the 18" wheels in the car mean. Pretty much all of us have the 18" wheels so this is the starting point or "zero" point for all.
For the 18" wheels my manual says:
All cars for the 245/40-R18 tire size the rim is 8.5 J x 18 H2, offset 48 mm.
For the wider 265/35 - R18 tire size the rim is 9.0 j x 18 H2, offset 54 mm.
For folks that do not know what the offset is (I was one of them not long ago) you can think of it as follows:
You take the wheel width, say the 8.5". Change this to millimeters, i.e. it is 8.5 x 25.4 mm = 215.9 mm. Now we divide this by 2 and get 107.95 mm.
The offset means how far the wheel mounting surface of the hub is from the wheel width center point in the wheel. If this wheel was with zero offset (wheel would mount in the center of the width on the hub) it would position the outer edge of the wheel 107.95 mm outward from the wheel mounting surface on the hub.
But, in our cars this wheel has an offset of +48. This means that the wheel mounting surface on the wheel is moved from the center of the wheel width by 48 mm and the positive offset means that the mounting surface is moved outward in the wheel, like the wheel is pushed under the car.
The positive 48 mm offset sets the outer edge of the wheel aligned with the fender like it is in our cars and this is the "zero point" for us. With zero offset this wheel would stick out from under the car by that 48 mm.
Above calculation positions the outer edge of the 8.5 J x 18 H2 wheel to 59.95 mm (107.95mm - 48mm = 59.95mm) outward from the wheel mounting surface of the hub.
For the wider 9.0" wheel with the bigger 54 mm offset this distance is 60.30 mm, i.e. the rear wheel outer edge is 0.35 mm (0.014") further away from the wheel mounting surface.
So the zero point for us is the about 60 mm distance between the wheel mounting surface and the outer edge of the wheel.
For myself I am planning to get 17" wheels just to soften the ride a little bit and also possibly to save the new wheels from pot hole damage that cause vibrations at highway speeds. This car with the 5.5 L engine is made to drive fast but we cannot drive fast enough to need the 18" rims for handling and for me the looks is not that important if the wheels otherwise look ok. And 17" wheels don't look that bad on this car.
I'm planning to get a wheels that are 7.5" wide with +40 mm offset. This positions the outside edge of the new wheels at 55.25 mm from the mounting surface, i.e. about 5 mm in from where they now are. I am perfectly fine with this change as I kind of don't like those rear wheels being wider than the fender at the bottom anyway. The 5 mm move in will take about half of this away.
I will have to let the staggered setup go but this is fine too. Will allow me to rotate the tires that I now cannot do.
Last edited by Arrie; 11-30-2014 at 03:36 PM.
#17
Wheels and Tires
In my 2010 E550 manual for the 17" wheels it says:
E350 Luxury, E350 Luxury BlueTec and E550 Luxury - 8.0 J x 17 H2, offset 48 mm.
E350 Sport BlueTec - 8.5 J x 17 H2, offset 48 mm.
The wheel width is 0.5 inches wider with the sports model. I guess they enhance the sports look by using 0.5" wider rim with the same 48 mm offset, which pushes the outer edge of the wheel out by 6.35 mm (1/4").
What is important for anybody thinking of going with different size wheels is to know what the 18" wheels in the car mean. Pretty much all of us have the 18" wheels so this is the starting point or "zero" point for all.
For the 18" wheels my manual says:
All cars for the 245/40-R18 tire size the rim is 8.5 J x 18 H2, offset 48 mm.
For the wider 265/35 - R18 tire size the rim is 9.0 j x 18 H2, offset 54 mm.
For folks that do not know what the offset is (I was one of them not long ago) you can think of it as follows:
You take the wheel width, say the 8.5". Change this to millimeters, i.e. it is 8.5 x 25.4 mm = 215.9 mm. Now we divide this by 2 and get 107.95 mm.
The offset means how far the wheel mounting surface of the hub is from the wheel width center point in the wheel. If this wheel was with zero offset (wheel would mount in the center of the width on the hub) it would position the outer edge of the wheel 107.95 mm outward from the wheel mounting surface on the hub.
But, in our cars this wheel has an offset of +48. This means that the wheel mounting surface on the wheel is moved from the center of the wheel width by 48 mm and the positive offset means that the mounting surface is moved outward in the wheel, like the wheel is pushed under the car.
The positive 48 mm offset sets the outer edge of the wheel aligned with the fender like it is in our cars and this is the "zero point" for us. With zero offset this wheel would stick out from under the car by that 48 mm.
Above calculation positions the outer edge of the 8.5 J x 18 H2 wheel to 59.95 mm (107.95mm - 48mm = 59.95mm) outward from the wheel mounting surface of the hub.
For the wider 9.0" wheel with the bigger 54 mm offset this distance is 60.30 mm, i.e. the rear wheel outer edge is 0.35 mm (0.014") further away from the wheel mounting surface.
So the zero point for us is the about 60 mm distance between the wheel mounting surface and the outer edge of the wheel.
For myself I am planning to get 17" wheels just to soften the ride a little bit and also possibly to save the new wheels from pot hole damage that cause vibrations at highway speeds. This car with the 5.5 L engine is made to drive fast but we cannot drive fast enough to need the 18" rims for handling and for me the looks is not that important if the wheels otherwise look ok. And 17" wheels don't look that bad on this car.
I'm planning to get a wheels that are 7.5" wide with +40 mm offset. This positions the outside edge of the new wheels at 55.25 mm from the mounting surface, i.e. about 5 mm in from where they now are. I am perfectly fine with this change as I kind of don't like those rear wheels being wider than the fender at the bottom anyway. The 5 mm move in will take about half of this away.
I will have to let the staggered setup go but this is fine too. Will allow me to rotate the tires that I now cannot do.
E350 Luxury, E350 Luxury BlueTec and E550 Luxury - 8.0 J x 17 H2, offset 48 mm.
E350 Sport BlueTec - 8.5 J x 17 H2, offset 48 mm.
The wheel width is 0.5 inches wider with the sports model. I guess they enhance the sports look by using 0.5" wider rim with the same 48 mm offset, which pushes the outer edge of the wheel out by 6.35 mm (1/4").
What is important for anybody thinking of going with different size wheels is to know what the 18" wheels in the car mean. Pretty much all of us have the 18" wheels so this is the starting point or "zero" point for all.
For the 18" wheels my manual says:
All cars for the 245/40-R18 tire size the rim is 8.5 J x 18 H2, offset 48 mm.
For the wider 265/35 - R18 tire size the rim is 9.0 j x 18 H2, offset 54 mm.
For folks that do not know what the offset is (I was one of them not long ago) you can think of it as follows:
You take the wheel width, say the 8.5". Change this to millimeters, i.e. it is 8.5 x 25.4 mm = 215.9 mm. Now we divide this by 2 and get 107.95 mm.
The offset means how far the wheel mounting surface of the hub is from the wheel width center point in the wheel. If this wheel was with zero offset (wheel would mount in the center of the width on the hub) it would position the outer edge of the wheel 107.95 mm outward from the wheel mounting surface on the hub.
But, in our cars this wheel has an offset of +48. This means that the wheel mounting surface on the wheel is moved from the center of the wheel width by 48 mm and the positive offset means that the mounting surface is moved outward in the wheel, like the wheel is pushed under the car.
The positive 48 mm offset sets the outer edge of the wheel aligned with the fender like it is in our cars and this is the "zero point" for us. With zero offset this wheel would stick out from under the car by that 48 mm.
Above calculation positions the outer edge of the 8.5 J x 18 H2 wheel to 59.95 mm (107.95mm - 48mm = 59.95mm) outward from the wheel mounting surface of the hub.
For the wider 9.0" wheel with the bigger 54 mm offset this distance is 60.30 mm, i.e. the rear wheel outer edge is 0.35 mm (0.014") further away from the wheel mounting surface.
So the zero point for us is the about 60 mm distance between the wheel mounting surface and the outer edge of the wheel.
For myself I am planning to get 17" wheels just to soften the ride a little bit and also possibly to save the new wheels from pot hole damage that cause vibrations at highway speeds. This car with the 5.5 L engine is made to drive fast but we cannot drive fast enough to need the 18" rims for handling and for me the looks is not that important if the wheels otherwise look ok. And 17" wheels don't look that bad on this car.
I'm planning to get a wheels that are 7.5" wide with +40 mm offset. This positions the outside edge of the new wheels at 55.25 mm from the mounting surface, i.e. about 5 mm in from where they now are. I am perfectly fine with this change as I kind of don't like those rear wheels being wider than the fender at the bottom anyway. The 5 mm move in will take about half of this away.
I will have to let the staggered setup go but this is fine too. Will allow me to rotate the tires that I now cannot do.
My question is why go to a 7.5"? What size tire?
#18
MBWorld Fanatic!
Joined: Oct 2010
Posts: 4,552
Likes: 942
From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
The 7.5" width just happens to be the width of the AR 883 Maverick 17" wheel that my local wheels dealer can get easily and it does not look bad on my Steel Gray car, the Anthracite Machined one. In the picture below it is shown as 17"
Last edited by Arrie; 11-30-2014 at 03:50 PM.
#19
Wheels and Tires
To keep the speedo in check it is the 245/45 - R17 tire.
The 7.5" width just happens to be the width of the AR 883 Maverick 17" wheel that my local wheels dealer can get easily and it does not look bad on my Steel Gray car, the Anthracite Machined one. In the picture below it is shown as 17"
The 7.5" width just happens to be the width of the AR 883 Maverick 17" wheel that my local wheels dealer can get easily and it does not look bad on my Steel Gray car, the Anthracite Machined one. In the picture below it is shown as 17"
Remember the aspect ratio is different
The inch comes out of the tire wall height.
I tend not to go narrower on the wheel by habit but it should be fine.
Enjoy.
#20
MBWorld Fanatic!
Joined: Oct 2010
Posts: 4,552
Likes: 942
From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
Of course the speedo will be correct on the 17 with the prescribed tire size of 245/45 17. The prescribed tire on the 18 with the 245/40 has the same circumference.
Remember the aspect ratio is different
The inch comes out of the tire wall height.
I tend not to go narrower on the wheel by habit but it should be fine.
Enjoy.
Remember the aspect ratio is different
The inch comes out of the tire wall height.
I tend not to go narrower on the wheel by habit but it should be fine.
Enjoy.
I think I will really enjoy the softer ride with 1/2" more rubber between the wheel and road surface.