What pressure to run in 235/40 18s
Thread Starter
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
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From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
What pressure to run in 235/40 18s
I will be replacing my stock staggered 17 inch set up next week with 235/40 18s all around. Is there a way of calculating what the pressures should be in the new tires by working off the stock recommended pressures or is it just an educated guess kind of thing?
Any info appreciated.
Any info appreciated.
Thread Starter
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
Likes: 28
From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
Wheels are coming in Thursday. Anyone with any advice?
What are you guys with factory 18s running?
What are you guys with factory 18s running?
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C 350
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Joined: Feb 2004
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From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
I will be replacing my stock staggered 17 inch set up next week with 235/40 18s all around. Is there a way of calculating what the pressures should be in the new tires by working off the stock recommended pressures or is it just an educated guess kind of thing?
Any info appreciated.
Any info appreciated.
Since I never have anyone in back, I'm using 35psi rear to soften the ride a little which it does. This has not resulted in increased tire wear although it MIGHT on other brands. At 30K miles, my Bridgestone RE-050As have at least 10K miles left before they are down to the wear bars in front.
Thread Starter
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
Likes: 28
From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
Thanks for the info guys. The shop recommended 35 front and 37 rear so that is what I am running right now. The great thing is that the ride feels better now than with my 17s.
Like RLE, I am almost always solo or at least no one in the back so I may even drop down a psi or two to see how it does.
As we have so much rain lately, I couldn't even get home without the car looking filthy(the new offset of 45 doesn't help with that either...) so I will post a few pics once I get her shined up.
One more question. Does changing over to a lighter wheel generally help with ride quality? It seems to make since as there is less weight flopping around to upset the car but just curious what others understanding is. I posted this on another tire/wheel thread floating around but didn't get any feedback so any info appreciated.
Like RLE, I am almost always solo or at least no one in the back so I may even drop down a psi or two to see how it does.
As we have so much rain lately, I couldn't even get home without the car looking filthy(the new offset of 45 doesn't help with that either...) so I will post a few pics once I get her shined up.
One more question. Does changing over to a lighter wheel generally help with ride quality? It seems to make since as there is less weight flopping around to upset the car but just curious what others understanding is. I posted this on another tire/wheel thread floating around but didn't get any feedback so any info appreciated.
