Wondering if a 165 x 15 donut would work as spare tire. I thought it might be possible. Although it would be quite lopsided, it might get you home.
Of course, you would have to strap the bad tire somewhere...

 

i highly doubt it would work, but do some tests before you throw it in the trunk --

(1) it has to fit over the caliper and rotor if you're putting it on the front --
(2) it has to be the same HEIGHT as the rear wheel and tire or you'll completely smoke your differential --

 

I have to buy to try...
anyway, if it fits the slk then it should fit the crossfire?
As far as smoking, i am thinking only short distance at 30 mph max. just to get out of a roadside deal with tow truck etc.

 

Remember, slk's have smaller wheels than your crossfire. You'd still have a major mismatch side to side.

 

If Mercedes puts the "donut" in a SLK320 as a spare, then there is really no reason we shouldn't be able to use it on our Crossfires. We use the same exact disc brakes, same lug pattern, and the wheels offset is close to ours. The Crossfire also has more than enough inner fender to accommodate a smaller tire.
Yes the SLK320 uses a smaller wheel than we do, but even though their wheels diameter is smaller than the Crossfires, the tires on both cars have approximately the same circumference due to the fact the XF uses a 40 & 35 series tire to the SLKs 55 & 50s respectively.
In Motor Trend, Dec. 2003 issue they did a comparison road test between the SLK320 and the Crossfire. Using the same trannys and axle ratios, both cars were turning 2250 rpm at 60 mph. That can only mean both cars had tires that were the same "height".
TYPHOON55, you were planning on doing the very same thing I was going to do. After reading about "The Crossfire Kids" flat tire experience, I decided I was going to buy the tire repair kit ANDREW recommended, and try to find an SLK spare.

 

I could be wrong but did the SLK 320 come with any kind of a spare? I want to say, no it didn't.

 

Fireamx - those figures are reassuring that it could work. I am thinking this is the best answer to getting out of a jam in the middle of the night or the middle of nowhere or both!
As a donut, and probably quite lopsided when installed, it would only be good for short distances at very slow speeds. At least it would get you home or somewhere safe until you can find a replacement.

Now the challenge is where to store the donut and a bigger challenge is where to put the flat.

 

BEN47,......Then I'm going to have a pretty hard time finding one if they never used em in the first place. How about a Mercedes C320 Sport Coupe. Do they have a spare?
There has to be some other Mercedes model with the same lug pattern as the SLK that uses the "donut" spare that Typhoon spoke of.
Come on people, we need some help here.

 

(Below is a pic of an SLK spare)

While I'm almost 100% postive these will not clear my calipers, it should work for the base owners as an emergency fix...

 

Respdoc...Thanks for the photo of the SLK spare. That gives all the Limited and base cars a chance to have a little extra "insurance" when they're out on the road, a million miles from nowhere. Like you said, I don't know if they would fit over SRTs 13" rotors since the SLK never had them. Once again, thanks for your input.

 

The SLK32 AMG came with the same spare I believe. I have a limited coupe and am now going to buy the SLK's spare to pop in my trunk for a "just incase". No more Fix A Flat!