Replacement for factory Mini-spare tire (AKA Donut)

[DPDISXR4Ti]

So what you could do is replace the 125/90R16 tire on the Mercedes wheel with a 115/70R16 tire. I did a quick study and found several modern vehicles that could donate the requisite spare tire (only) which could then be mounted onto the Mercedes rim...

1999 - 2008 Saab 9-5

Some time since I last posted on this thread I stopped by the junkyard and picked up a spare from the aforementioned Saab 9-5. My experience with Saab spares is that they didn't cheap out on the tires like many others. I have one out in the garage from an early 80's Saab 900 that still looks new. Any way, as I suggested above, I took the Mercedes and Saab spares to my friendly mechanic and asked him to mount the tire from the Saab spare onto the Mercedes rim.

Not so fast... The valve stem on the Mercedes has failed - very common I come to find out - and it is not a common size at all! Some research and I find it's a TR438, which is available on-line (or from a Mercedes dealer for $15). One week later, I have the valve stem, back to my mechanic, and I now have a 16" spare for the Scorpio which snugly fits into the wheel well.

ScorpMercSaabSpare-1.JPG (1.05 MiB) Viewed 3128 times

ScorpMercSaabSpare-2.JPG (1.06 MiB) Viewed 3128 times

Bonus points for having a nice flat surface. If I wanted to skip that masonite panel that goes over the spare well, I could.

[brokencase]

Very cool!

[DAReese]

My spare tire on the left. Never been on the car before. I found a newer car in the Pull-A-Part that had the same size spare and had it mounted on the original rim.

Spare Tire XR4Ti 4.jpg (1.83 MiB) Viewed 2951 times

[DPDISXR4Ti]

I found a newer car in the Pull-A-Part that had the same size spare and had it mounted on the original rim.

Years ago I did the same, using a spare tire from a Saab 900 I believe. Then I installed bigger brakes, which didn't clear the factory spare wheel. By then, word on the street was that some of the sportier Saab 9000s had a 16" spare which could be used as-is (4x108 bolt pattern).

As you can see, the process was a little more involved for the Scorpio.

[Bob Weir]

I often thought about cutting out the "brace" at top rear of wheel well. If needed for structural rigidity, plates at each end with nuts & bolts to reattach it. The well is deep & wide enough for most standard tires