Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Topic: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5 (Read 4215 times) previous topic - next topic

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #25 – March 16, 2021, 06:46:07 pm

Quote from: cucotx – March 16, 2021, 06:26:57 pm

After much boring research into truck/bus tires, I have decided to go with 8 of the Michelin X COACH H LZ LRH, sized 295/80R22.5.
BTW, I do have an email out to FOT to confirm that I can install the 295/80 on the 2004 U320 4020 before I order them.

[/quote]
Make sure FOT gives the go ahead for clearance to the airbags, etc. The new tire will be about 1.1 inches taller so interference is possible. The taller tires will also cut the tire to fender well distance in the back. 295/80-R22.5 vs 295/75-R22.5 Tire Comparison - Tire Size Calculator | Tacoma...

Pierce

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #26 – March 16, 2021, 06:48:11 pm

Quote from: cucotx – March 16, 2021, 06:26:57 pm

I also plan to install the Centramatic wheel balancing system. For now, I'm assuming that all 8 tires would need the Centramatics on it?

On a motorhome with dual rear drive wheels, the Centramatic goes between the rear wheels on each side, so you need a total of 4 Centramatics to do all 4 corners of the coach. See the installation videos:

Tire Balancers, Tire Balancing, Wheel Balancer and Wheel Balancing from...

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #27 – March 16, 2021, 09:05:48 pm

Quote from: Pierce & Gaylie Stewart – March 16, 2021, 06:46:07 pm

The new tire will be about 1.1 inches taller so interference is possible.

Hi Pierce,

I think the concern for the clearance to anything around the tire would be the sidewall height difference at 0.58" when comparing the 295/75 to the 295/80. I'm thinking the other 0.58" size change with the 295/80 that is below the axle just lifts the MH off the road. So I think I just need 0.58" clearance.

When compared to the original 275/80 from the factory, the 295/80 would have an additional sidewall height of about 0.63" that would need clearing.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #28 – March 16, 2021, 09:08:16 pm

Chuck and Jeannie,

I'm also assuming that the tag axle would need two centramatics for those tires as well?

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #29 – March 16, 2021, 09:25:11 pm

Quote from: cucotx – March 16, 2021, 09:05:48 pm

Hi Pierce,

I think the concern for the clearance to anything around the tire would be the sidewall height difference at 0.58". I'm thinking the other 0.58" size change with the 295/80 that is below the axle just lifts the MH off the road. So I think I just need 0.58" clearance.

You are correct in that it will come just over a half inch closer to the top of the wheel well and the same in the front. But 0.58 may touch the bottom of the air bag plate a lot more than our 295/70 where the contact is only in certain turns and attitudes. FOT will know exactly how much.

Pierce

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #30 – March 16, 2021, 09:31:52 pm

Quote from: cucotx – March 16, 2021, 09:08:16 pm

I'm also assuming that the tag axle would need two centramatics for those tires as well?

I guess that would be logical. To tell the truth, I've never thought about the tag axle wheels, cuz we don't have one.

Found a previous discussion thread where several members mentioned having them installed on the tag axle:

Centramatic balancers - would like to hear opinions

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #31 – March 16, 2021, 09:48:36 pm

I have them on our tag axle

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #32 – March 17, 2021, 10:15:45 am

Quote from: rbark – March 16, 2021, 09:48:36 pm

I have them on our tag axle

Richard,
On your U320, do you use 600-630 on both steer and tag axles and the 600-640 Centramatic on the drive axle?

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #33 – March 17, 2021, 04:16:41 pm

The response for my email to FOT is as follows:

"The 2004 U320 was equipped with a 275-80R/22.5 tire and we recommend replacing it with the same size. "

The above from the "Director of Warranty and Technical Support".

They didn't say the 295/80 won't fit. But, it is the correct response that I would expect from any manufacturer to a question like this via email. I wasn't hopeful that they would confirm that it would fit, even if it does. All their warranty work and design is based on the 275/80. I suppose a concern from a manufacturer is that people will use beefier tires and then end up overloading the axle, frame or other components with weight in the coach above the GAWR. I think what I'll do is wait until I get the RV and take clearance measurements to see if I can fit the 295/80.

Valento got a different response from FOT to the same question for his 2004 U320 3820 and the tires had clearance. So, I would think it should fit a 2004 U320 4020.

Now, from a design point of view, other than the clearance issues, I wonder if the weight difference between the 295/80 tire and the 275/80 tire would be large enough to make a difference to the 22.5 wheel and/or axle. The 295/80 should not be more than about 20 lbs heavier than the 275/80. So, I would think that should not be of concern to the axle or wheel. Does anyone know?

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #34 – March 17, 2021, 04:50:12 pm

I believe 295-75R/22.5 is the same dimensions as the 275.80R/22.5

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #35 – March 17, 2021, 04:55:32 pm

Peter, as to the size of my centermatics, I have no idea. Although I have had my tires changed, I wasn't around till they were done.
Not sure but I think the company's web site will have that information.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #36 – March 17, 2021, 04:57:26 pm

Quote from: oldguy – March 17, 2021, 04:50:12 pm

I believe 295-75R/22.5 is the same dimensions as the 275.80R/22.5

They're almost the same size, but Michelin doesn't sell the "X Coach" in the 295/75 size.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #37 – March 17, 2021, 05:08:43 pm

Quote from: oldguy – March 17, 2021, 04:50:12 pm

I believe 295-75R/22.5 is the same dimensions as the 275.80R/22.5

Just about exactly the same diameter but the aspect ratio on the 295/75 does mean the 7.3% wider tire polishes the bottom plate on the air bag. At least it does on ours. So what does that mean on a taller 295/80?

No real problem on the back.

Pierce

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #38 – March 17, 2021, 05:15:25 pm

Quote from: Pierce & Gaylie Stewart – March 17, 2021, 05:08:43 pm

Just about exactly the same diameter but the aspect ratio on the 295/75 does mean the 7.3% wider tire polishes the bottom plate on the air bag. At least it does on ours. So what does that mean on a taller 295/80?

No real problem on the back.

Pierce

But Pierce, the part I don't understand is why does it clear on the 2004 3820 U320? Could it be that the spacing for your U300 for the wheel is different for that of the U320.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #39 – March 17, 2021, 05:51:53 pm

Quote from: cucotx – March 17, 2021, 05:15:25 pm

But Pierce, the part I don't understand is why does it clear on the 2004 3820 U320? Could it be that the spacing for your U300 for the wheel is different for that of the U320.

You didn't give the tire size on the U320. Are you saying the 295/80R22.5 clears on the U320? If so, you are probably home free.

Pierce

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #40 – March 17, 2021, 06:00:06 pm

Valento installed the 295/80 on his U320 3820. I wonder how much clearance he has with the bottom of the mounting to the airbags?

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #41 – March 17, 2021, 06:02:07 pm

May partially depend on what CUT ANGLES are set in the Sheppard steering box.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #42 – March 17, 2021, 06:07:55 pm

Quote from: wolfe10 – March 17, 2021, 06:02:07 pm

May partially depend on what CUT ANGLES are set in the Sheppard steering box.

Yea. It would be nice if we had others in the forum that have tried the bigger tires in the U320 and could comment on this.

Brett, do you think an extra 20 lbs with the bigger tire would be an issue with the U320 wheel, axle or other component? Other than clearance, that would be the remaining concern.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #43 – March 17, 2021, 06:10:47 pm

Sorry, no first experience.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #44 – March 17, 2021, 06:12:58 pm

Quote from: cucotx – March 17, 2021, 06:07:55 pm

Yea. It would be nice if we had others in the forum that have tried the bigger tires in the U320 and could comment on this.

Brett, do you think an extra 20 lbs with the bigger tire would be an issue with the U320 wheel, axle or other component? Other than clearance, that would be the remaining concern.

Same width, just taller so your revs per mile would be less. Not a bad thing. If I were sure it cleared the front bags, I would probably mount the taller size.

Pierce

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #45 – March 17, 2021, 06:41:45 pm

I believe the 295-75R/ 22.5 is the same dimensions as the 275-80R/22.5 or very close.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #46 – March 17, 2021, 06:44:39 pm

Quote from: oldguy – March 17, 2021, 06:41:45 pm

I believe the 295-75R/ 22.5 is the same dimensions as the 275-80R/22.5 or very close.

Correct.

But, 275/80 to 295/80 is different.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #47 – March 17, 2021, 07:17:34 pm

All anyone has to do is type in any two sizes 275/80-R22.5 vs 295/75-R22.5 Tire Comparison - Tire Size Calculator | Tacoma... and you get the all the information including speedo error plus you can overlay the tires. It's a no brainer. Should end any arguments.

   275/80-22.5    295/75-22.5    Difference
Diameter inches (mm)      39.82 (1011.5)    39.92 (1014)    0.1 (2.5) 0.2%
Width inches (mm)      10.83 (275)    11.61 (295)    0.79 (20) 7.3%
Circum. inches (mm)      125.11 (3177.72)    125.42 (3185.57)    0.31 (7.85) 0.2%
Sidewall Height inches (mm) 8.66 (220)    8.71 (221.25)    0.05 (1.25) 0.6%
Revolutions per mile (km) 506.45 (314.69)    505.2 (313.91) -1.25 (-0.78) -0.2%

Pierce

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #48 – March 17, 2021, 09:09:29 pm

The larger, heavier tire will slow down the acceleration and cost a little fuel use.

Re: Tires - Michelin 2004 U320 - Steer vs. Drive tires - 275/80R22.5 vs. 295/80R22.5

Reply #49 – March 17, 2021, 09:17:48 pm

I would measure how close the 275/80r 22.5 is to the lower plate in front while turning and then compare the diameter of the 2 sizes to make a comparison. On our 98 I took it to a tire place and he told me that he had put a larger tire on it. As I left the lot when I turned the wheels it rubbed real hard. Took it back the next day and he put on 295/75r22.5 tires and no rubbing but I don't know what size he had put on first.

Affiliate Notice