Tire size

[Roger&Patti]

Can someone tell me what the tallest and widest tire will fit a 2004 Monaco Diplomat?

[Skip426]

Installation of oversize tires can lead to a number of issues with power on hills , as the added height can drop the engine out of it's power band, as well as the clearance to body problems.
Rim width and offset for dual spacing , is a big consideration too.

Do you have an issue that you think the bigger tires will correct ?

[vito.a]

First we need to know what size tires Monaco specified for your coach. That should be on the placard on the wall next to the driver.
Some of us have upgraded the front tires so we can run less pressure and still carry the weight. We did have to check for clearance at full lock.
You do need to be careful installing larger tires on dual wheels. The tires require proper spacing for cooling.

[wolfe10]

Yup, need to know:


Current tire size


Current GAWR's


Wheel size (width)

[rpasetto]

Make sue tires in the size you choose are rated for your wheel size.

[Kid Gloves]

I’m curious as to why the OP is looking for the “tallest and widest” tires.

I’d also like to know how, if we know the current tire size, current GAWR’s (do axle ratings change over time?) and wheel size, we will be able to determine the tallest and widest tire that will fit on the OP’s coach.

[Roger&Patti]

I have 275/70R22.5 tires with 8.25 rims. I need new tires so I hear from some people that a little wider tire in the front helps handling and that 275/80R22.5 ride a little smother.

[96 Wideglide]

275/80's are only going to be a little taller than your stock 275/70's.

[vito.a]

The 275/80R22.5 is 39.8" in diameter and the 275/70R22.5 is 37.7" in diameter.
That's a 5.6% increase.
The Rev's per mile is 507 vs 536 so the speedometer will be off.
The width is the same (275mm).
But, the sidewall is 1.1" larger so they may not work on your rear duals.

[Skip426]

Matching RPM ( Revolutions Per Mile; in tire talk ) is important front to rear , to much difference can lead to problems with ABS ( Anti-lock Braking Systems ).

[Kid Gloves]

Originally Posted by 96 Wideglide

275/80's are only going to be a little taller than your stock 275/70's.

Here’s the difference.

The 295, with a lower profile, has a nearly identical sidewall height as the 275.

To be clear, I am not recommending anything other than the OEM tire size specified by the manufacturer for your coach.

[wolfe10]

Not familiar with 295/65R22.5.


Not sure I would consider that short a sidewall even if available-- short side wall= less flex= rougher ride.

[Kid Gloves]

Originally Posted by wolfe10

Not familiar with 295/65R22.5.


Not sure I would consider that short a sidewall even if available-- short side wall= less flex= rougher ride.

I just plugged in numbers until something came up with the same circumference as the OEM tires. The OP wants a wider and taller tire. The obvious problem is that going wider and taller gets bigger in a hurry. Aspect ratio being what it is.

The 295/65, if available, has the same height sidewall as the 275/70, just on a wider tire. From my perspective, fussing with tire sizes or a few psi of tire pressure to resolve ride quality or handling issues is an exercise in futility.

[Roger&Patti]

Ok, I`m going to stay with the same size. Now will either use Goodyear G670 or Michelin possibly X Multi Z as they don`t make the XZA2 anymore.