Different tires, same pressure?

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Jul 14, 2020
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So I changed my 205-65-15 inch tires to 205-55-16 tires, on 16 inch wheels of course, and wondering if since the sidewall is now shorter, if I should still run the stock 35 psi or is another psi more appropriate?
 
So I changed my 205-65-15 inch tires to 205-55-16 tires, on 16 inch wheels of course, and wondering if since the sidewall is now shorter, if I should still run the stock 35 psi or is another psi more appropriate?
The 55 series already has a stiffer sidewall and will ride firmer and harsher than the 65 series. Adding more psi will only make it worse, unless that is what you actually want.
 
I would do some experimenting. I just put new tires on my Buick and finally settled at 33ish. I was running 30 with the old tires so that's where I started but the steering seemed to have a slower response with the new tires so I started adding. When I hit 35 it was to responsive so I backed off.
 
The 55 series already has a stiffer sidewall and will ride firmer and harsher than the 65 series. Adding more psi will only make it worse, unless that is what you actually want.

A standard load 205/65R15 is a 94 rating. A standard load 205/55R16 is a 91.
 
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205/55 R16 isn't an appropriate replacement for 205/65 R15 as
they aren't same circumference. Both 205/60R16 and 205/65 R15.

However, if both sizes are used or suggested by the manufacturer
they certainly suggested tire pressures for respective sizes. Follow
the car manufacturer.

OP should provide ALL relevant spec incl load rating.
.
 
205/55 R16 isn't an appropriate replacement for 205/65 R15 as
they aren't same circumference. Both 205/60R16 and 205/65 R15.

However, if both sizes are used or suggested by the manufacturer
they certainly suggested tire pressures for respective sizes. Follow
the car manufacturer.

OP should provide ALL relevant spec incl load rating.
.
Maybe he meant 225/55R16
 
Were do you come up with this stuff? You don't even know the brand or model of tire.

I come up with this stuff because about a decade of working in the tire industry has most of this etched in my brain. Hence why I immediately knew the tire he put on was shorter.

I don’t need to know the brand or model because it doesn’t matter for load rating. Size does, and whether or not it is an extra load construction. Perhaps as Roofless mentioned he meant 225/55R16. That would be the appropriate size and load rating.

You’re welcome to look up a typical tire in the sizes mentioned in the OP and see the load ratings if you’d like. An XL (extra load, not extra large) version will typically be three or four points higher than the standard load ratings I mentioned earlier.
 
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Were do you come up with this stuff? You don't even know the brand or model of tire.
You don't need the brand or model. Ya' see, tires are standardized.

Long version: http://barrystiretech.com/loadtables.html

Short version: If you know the tire size, you know the load carrying capacity. Yes, it varies according to which of the 3 major tire standardizing organizations the tire is built to, but the major difference is the difference between measurement systems (Metric vs English)

For example: The European organization using metric units - a nice round rated pressure of 250 kPa (kiloPascals - named after Blaise Pascal) = 36.3 psi. where the US organization uses the nice round 35 psi = 241 kPa. That makes it seem like there are major differences, but the differences are really small - essentially the same.
 
I don’t need to know the brand or model because it doesn’t matter for load rating. Size does, and whether or not it is an extra load construction. Perhaps as Roofless mentioned he meant 225/55R16. That would be the appropriate size and load rating.
Well, I looked up those two different sizes for similar tires and they are BOTH load rated 94, 205/65/15: https://www.tirerack.com/tires/tire...65TR5WCO&vehicleSearch=false&fromCompare1=yes and 205/55/16: https://www.tirerack.com/tires/tire...HR6WCUXL&vehicleSearch=false&fromCompare1=yes Only the speed rating is different.
 
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