Forum Discussion
j-d
Jul 01, 2017Explorer II
Just found this quote in a search that turned me back to RV.net:
"I have an 85 gmc class c with 875 16.5 firestone transforce with no problem"
The question was actually about a different chassis, but this is part of what I wrote then, after a little research:
"According to "Tire Guide", the 8.00 and 8.75R16.5LT tires are "Light Truck Numeric" so the "Section Width" of the 8.75 is .75" (3/4") more than the 8.00s you have now.
If your dual spacing, between sidewalls at the closest point is now about 2.00" now, then taking 3/4" off leaves about 1.25". That's about what I saw when I just went out and looked at the duals on our E450. So guess-by-gosh looks like you can make the change and stay with 16.5" wheels. The difference in section width would be 3/8" on each side of each tire, so 3/4" total change in that gap."
If you want to go to the 875R16.5's, we have to be sure you end up with enough dual spacing that your sidewalls have the clearance they need to shed some heat, and NEVER NEVER "Kiss" when they bulge over bumps and dips in the road.
"I have an 85 gmc class c with 875 16.5 firestone transforce with no problem"
The question was actually about a different chassis, but this is part of what I wrote then, after a little research:
"According to "Tire Guide", the 8.00 and 8.75R16.5LT tires are "Light Truck Numeric" so the "Section Width" of the 8.75 is .75" (3/4") more than the 8.00s you have now.
If your dual spacing, between sidewalls at the closest point is now about 2.00" now, then taking 3/4" off leaves about 1.25". That's about what I saw when I just went out and looked at the duals on our E450. So guess-by-gosh looks like you can make the change and stay with 16.5" wheels. The difference in section width would be 3/8" on each side of each tire, so 3/4" total change in that gap."
If you want to go to the 875R16.5's, we have to be sure you end up with enough dual spacing that your sidewalls have the clearance they need to shed some heat, and NEVER NEVER "Kiss" when they bulge over bumps and dips in the road.
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