moving from 225R75/16 to 235R85/16 PROBLEMS

Hi pnichols,

Everything I've read suggests that wider tires have less rolling resistance than narrower ones. The brands I'm considering are Michelin and Toyo.

pnichols wrote:
Don,

I'd recommend looking at going to a Load Range E 215/85R16 set of tires - I did in the summer of 2011. This is actually a taller tire (about 1.2 inches larger diameter than the stock 225/75R15 size), so you wind up with about 0.6 inches of more ground clearance. The load versus pressure ratings are identical for the two Load Range E tires. The tread width is about 0.5 narrower with the 215/85R16 size, so you get better air cooling between the rear duals. If you get Michelins, you also get slightly better gas mileage from their 215/85R16 tires because they have less rolling friction.

Think about it, unless you really need the higher load capacity of the 235's!

robatthelake wrote:
Use the original stock size Rims and Tires. I can see no reason to change something that works.

There are several cases I have read recently where someone went to get new tires only to be told "They don't make that size anymore"

In fact.. I expect to hear that when I go to get new tires.

When this happens... Changing or scrapping are your only options.

I'm struggling with the idea that the wheels from an F-450 don't fit on an E-450. A bit more explanation is in order.

Interesting idea. IMO Michelins are also more likely to have the highest safety margin built in above and beyond the ratings in their inflation tables. There was a reason they would allow you to run 7 years instead of 5 (I wonder if that is still true).

Blow outs and delaminations on properly cared for C tires for vehicles near their weight limits always used to be heavily biased toward the inner tires of the pair, probably because of reduced cooling. The most margin in the tire (by carefully selecting brand and model - was once XPS as the very best) along with extra dually spacing could be a good answer.

But it does take 4 or 6 wheels which gets expensive. Simply upgrading the tires to the best available can also go a long way toward increasing margin on weight and ride quality.

Jim

Don,

I'd recommend looking at going to a Load Range E 215/85R16 set of tires - I did in the summer of 2011. This is actually a taller tire (about 1.2 inches larger diameter than the stock 225/75R15 size), so you wind up with about 0.6 inches of more ground clearance. The load versus pressure ratings are identical for the two Load Range E tires. The tread width is about 0.5 narrower with the 215/85R16 size, so you get better air cooling between the rear duals. If you get Michelins, you also get slightly better gas mileage from their 215/85R16 tires because they have less rolling friction.

Think about it, unless you really need the higher load capacity of the 235's!

Hi Hitech,

Changing to an F-450 axle does not sound cheap.

Hmm I wonder what Quigly uses when they convert E series to 4WD? Maybe they put in an F series axle as part of the conversion. I could SWEAR somewhere in my foggy memory I've seen someone successfully do what you want to...

Jim

Hi Jim,

Apparently not.

HiTech wrote:
So there are no alternate offset outer wheels that will accommodate the E450 axle with no spacer required?

Jim

So there are no alternate offset outer wheels that will accommodate the E450 axle with no spacer required?

Jim

Use the original stock size Rims and Tires. I can see no reason to change something that works.