Believer45

Width is the same, 235 millimeters at the widest point of the sidewall. (235/50R17 and 235/55R17). 50 means the sidewall height is 50% of the width (117.5 millimeters), 55 means the sidewall height is 55% of the width (129.5 millimeters). From Consumer Reports on decoding tire size;

That has been my experience since my first car, a 1960 Dodge purchased 52 years ago. My question was not what is OEM size, my question was if there was room to go a bit larger than OEM. "Geeze" to quote you.

My appreciation to all three of you for taking time to share your expertise. The three of you have convinced me that my idea is not wise, I will go with the OEM size. Thank you again, and also for your patience with a rather stubborn old man. Dave / Believer45

Bbf2530, I appreciate your taking time to reply. I have talked to a couple of tire shops and checked online at several suppliers. In my experience tire shop employees for the most part stick to the company line to avoid liability. Example from my distant past, I had a 1964 1/2 Ford Mustang six cylinder that came with 13" rims. I bought 14" rims for the back and put on a significantly larger (probably 6" taller, it raised the back of the car 3 or 4") tire with the original suspension and no issues whatever. Same thing on a 1967 Chevrolet Impala, all four tires on a 1972 Ford Pinto station wagon, all four tires on a1995 Ford F250 2 wheel drive, all four on a 2003 Honda Odyssey and probably a few others I have forgotten about. Online retailers also seem to revert to the factory sizes. I did find a thread on another Fusion forum from a Fusion owner who said a 225/45R19 will fit and it is virtually the same diameter as the 235/55R17 I want to use although it is 10mm narrower. I have also looked at the wheel wells on my car and it appears to me there is ample room for a tire that is a bit under 1/2 inch larger radius and (most important) no wider than the OEM tire as there is not a lot of room between the fender and the sidewall on the rear when suspension is compressed. I am just looking to correct my speedometer error and thought I would take the opportunity. I was hoping someone else had used this size and could tell me their experience. Thanks again for your advice ------ Dave / Believer45

I have a 2015 Fusion SE that has OEM 235/50R17 tires on it and speedometer is off by about 3%. I am replacing the tires and would like to know if a 235/55R17 will fit. Anybody tried this size? Looks like diameter is .93" more than 235/55. Width and such remains the same. I cannot find any posts here of someone who tried this size. Thanks for your time. Dave / Believer45