18" Tire Replacement

[hs5870]

I have a 2024 silverado diesel dually ltz that came with 235/80r18 tires. At 27000 miles they need to be replaced. I haul a 35' 5th wheel with truck . Only Michilin makes the replacement tire , Has anyone put on 245/75r18 tires & is it an issue with the rear tire gap with a load on?

 

[newdude]

1 hour ago, hs5870 said:

I have a 2024 silverado diesel dually ltz that came with 235/80r18 tires. At 27000 miles they need to be replaced. I haul a 35' 5th wheel with truck . Only Michilin makes the replacement tire , Has anyone put on 245/75r18 tires & is it an issue with the rear tire gap with a load on?

 

 

 

There are two tires I see in 245/75R18 on Tire Rack and none of them are E load 121 load index.  So no, won't work.  

[hs5870]

yokohama makes the geolandar all terrain in 245/75r18 inan E rating. My concern is the Traction width (gap) between the rear tires with a load

 

[Randal Scott]

On the older duallies, you couldn't use 245s because the tires would touch. 

[Rick_]

Measure the clearance between the duals with and without the fiver hooked up.  This is to get an idea if the tires bulge much with a load.

If the clearance is greater than 30mm when loaded, then the 245s, being 10mm wider than the 235s, but only 5mm wider on one side, there would be 20mm clearance with the 245s.  If there is only 10mm clearance on the 235s when loaded, then the 245s are a no go.