05' W211 E320 CDI


I recently picked this car up and the previous owner put some factory Mercedes bbs 17" wheels instead of the standard 16". This means the tires are now 245/45 17 instead of the standard 225/55 16. Since I'm not looking for performance out of a 4k lb diesel but rather economy I am wondering if I should put some skinnier tires on.
The increase in diameter is a good thing for fuel mileage but not the increase in width and weight.
What is the most acceptable skinny tire to put on a 17x8.5 rim without compromising too much on ride and safety?
I imagine a 225's would be a bit stretchy though I have seen winter wheel combos running that size tire on a 17x8.5...
235's would be easy but would it be skinny enough to be worth it?

Once a size is determined then I need to find the right tire. I am a big fan of the LRR (low rolling resistance) tires, and particularly the little bridgestone ecopia's on my gf car. They do make them in the correct size/speed rating, but not sure on the load rating and ride quality on a heavier car like the E class.
I hear a lot about the extreme conti DWS all seasons being excellent and they do run these sizes as well but I don't believe are LRR.

What would be the best skinny size for the 17X8.5 wheels, and what would be the most efficient tire without completely destroying the nice ride of the merc?

Thanks.

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190D SOLD
2.5 non turbo
5 speed manual transmission
Build date: December 1985
W211 E320 CDI
W126 350SDL
X204 GLK 250 Sans Bluetec

I know Tirerack is a sponsor here, but don't know if their website will give you the same info you can find on DiscountTire.com.

The questions you have are about "Plus Size" wheels and tires and the DT website will give you all your Plus Size options. PM me if you'd like some help.

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'89 260e (212K Mi.), '92 400e (208K Mi.), '92 400e (not a misprint) (146K Mi.), '95 C220, '81 240D--Sold

Are you sure the tires currently on the car are 245/45/17's? I did a little research & the biggest tire you "should be able" to run on 17" wheels is a 225/50/17. Any size larger than 225/50 will usually rub somewhere in the wheel well. Just asking, because that's what I'm finding initially.

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'89 260e (212K Mi.), '92 400e (208K Mi.), '92 400e (not a misprint) (146K Mi.), '95 C220, '81 240D--Sold

I will need to pm you as I didn't know about "plus size" rims and what is the best tire/size combo



Positive. My old turbo e36 m3 had 265/40 17 all around and the car was lowered. The e320 definitely has more room than that so rubbing shouldn't be an issue. Regardless I want skinny tires with a good ride quality

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190D SOLD
2.5 non turbo
5 speed manual transmission
Build date: December 1985
W211 E320 CDI
W126 350SDL
X204 GLK 250 Sans Bluetec

Ride quality is tied more to sidewall height than outer diameter. A taller sidewall gives more compliance than a thinner one. I'm not sure LRR tires and ride quality go together. Something has to be stiffer in a LLR tire to give less resistance.

For what you are looking for, I'd probably sell off the 17" and go with factory 16" with stock tire size.

I'd stay the suspension is tuned for the wider stock tires.If you go thiiner less high speed corners you can take.Skinny tires do give more weight per sq. inch.That means you'll go better in snow,and tend to not do burnouts.But are cars a heavy stay with your load rating.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

The Continental Pure Contact All Season tires are LRR....They are available in 225 R50 17's and should fit the bill nicely. I have these in 16's on my 400 E and they are great.

The general rule of thumb is width+1" converted to mm is proper fittment for performance. On a 8.5" wide wheel that's 241mm and a 245 is the right width. Putting something equal to wheel width is some drift bro stuff and acceptable which would be 215. Any less than that and you're stretching the tire like a kid with his civic.

Agreed. Going with a stock wheel diameter and more tire sidewall also makes it less likely that you'll bend a wheel hitting a pothole or road debris.

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Suppose you were an idiot, and suppose you were a member of Congress; but I repeat myself. - Twain