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Topic: ORED 9R22.5 vs 10R22.5 (Read 823 times) previous topic - next topic

ORED 9R22.5 vs 10R22.5

Hi all,

I'm currently working with Dave Ward on tires for my 1987 GV. I have 9R22.5 Toyo M170z on it currently. He doesn't have a 9R Michelin available but he does have a 10R22.5. My forum sleuthing indicates that Michelin 255/80R22.5 was a good replacement 7 years ago... is that still true?

Also, any comments on the Michelin XZE or XZLE line of tires?

Thanks as always
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: ORED 9R22.5 vs 10R22.5

Reply #1 –
If you have the Cat with 4 spd like mine . 
          I just removed the 295/75/22.5  from the rear, and installed the 9R.
 Now my cruise RPM  increased to  2350 at 64 true.  From 2200.  So I lost a few MPH cruise speed and slight fuel mileage.
  The 9R is about 38.3 OD.    The 295 is about 39.8 OD .  The 10 R is about 40.1 OD. 
 The 255/80/ is about 38.5 about the same as 9R.
    I would fit the tallest tire  on my bus next time. due to gearing and speed . 
 I would not fit a smaller OD tire ever again.
 Measure your fender wells tho. Mine are 41  and may need trimming a little at the edges.

Re: ORED 9R22.5 vs 10R22.5

Reply #2 –
Quote from: Protech Racing –
If you have the Cat with 4 spd like mine . 
          I just removed the 295/75/22.5  from the rear, and installed the 9R.
 Now my cruise RPM  increased to  2350 at 64 true.  From 2200.  So I lost a few MPH cruise speed and slight fuel mileage.
  The 9R is about 38.3 OD.    The 295 is about 39.8 OD .  The 10 R is about 40.1 OD. 
 The 255/80/ is about 38.5 about the same as 9R.
    I would fit the tallest tire  on my bus next time. due to gearing and speed . 
 I would not fit a smaller OD tire ever again.
 Measure your fender wells tho. Mine are 41  and may need trimming a little at the edges.
My fender wells measure the same. What size tire are you running on the front?
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: ORED 9R22.5 vs 10R22.5

Reply #3 –
I also have a local place that can get me some Toyo M154 tires that are 265/75R22.5 (38.4", almost exact same OD as my M170s). Out the door at $618/tire

Or Dave can get me 275/80R22.5 Michelins which are 40" in diameter at $601/ea + his $90 fee + whatever the shop charges to mount and balance ($50/ea?). So roughly $300 more for the michelins that may be running uncomfortably close to too big for up front.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: ORED 9R22.5 vs 10R22.5

Reply #4 –
 I had the 295 X 6 for 5 years, Swapped out the steers last year for 9R .  Steers about the same . maybe a little crisper with e 9R at 90# vs the 295 at 74# .    These buses will be at a light loading  on the tire load /pressure scale .
  Does your tach read the same  at Speed?  I have GPS , true speed.  My  OE speedo read about 9% high .
 I think that my gear is a 4;10 .  Love to have a 3.9

Re: ORED 9R22.5 vs 10R22.5

Reply #5 –
Yes, options near in size to the 9R22.5 are Michelin 255/80R22.5 and other's 265/75R22.5.

10R will change effective rear axle ratio (higher road speed for a given engine RPM).
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: ORED 9R22.5 vs 10R22.5

Reply #6 –
These need more gear. Not less .
 

Re: ORED 9R22.5 vs 10R22.5

Reply #7 –
I decided to go with the Toyos. Partly because they're a closer match in diameter and party because the local shop I've been dealing with has been fantastic and I'd like to build that relationship for the future.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.