Community Forums

Dave-Oh · 02-29-2016, 10:24 AM

I may be changing out tires again (don't ask) and my latest RV service manager has suggested that I go to Michelins from the Goodyears that I currently have (G670 RV 245/70R 19.5 G-rated). I have the 16,000lb GVWR chassis GCVR of 23000lb.
,
The Michelin XRV's are H-rated.

Max inflation on the GYs: 110 with 4540 lb capacity
Max inflation on the Michelins: 95 with a 4080 lb capacity

at 85 lbs (Thor recommended) for my rig:
Goodyears - Max load - single: 3740 Dual 3515
Michelins - Max load - single: 4080 Dual 3970.

there shouldn't be a problem, Right?

Front axle rated at 6500lb
Rear axle rated at 11000

Should be fine, even if fully loaded? Unless I'm missing something?

best

dave

Kahoona · 02-29-2016, 10:34 AM

Quote:

Originally Posted by Dave-Oh

I may be changing out tires again (don't ask) and my latest RV service manager has suggested that I go to Michelins from the Goodyears that I currently have (G670 RV 245/70R 19.5 G-rated). I have the 16,000lb GVWR chassis GCVR of 23000lb.
,
The Michelin XRV's are H-rated.

Max inflation on the GYs: 110 with 4540 lb capacity
Max inflation on the Michelins: 95 with a 4080 lb capacity

at 85 lbs (Thor recommended) for my rig:
Goodyears - Max load - single: 3740 Dual 3515
Michelins - Max load - single: 4080 Dual 3970.

there shouldn't be a problem, Right?

Front axle rated at 6500lb
Rear axle rated at 11000

Should be fine, even if fully loaded? Unless I'm missing something?

best

dave

Short answer- Yes
There is more though. You will not be using the inflation set by Thor. You need to download or look up the inflation from Michelin. You always go with the tire manufacturers pressure. You look up the tire then the maximum load and position on the vehicle and it gives you the pressure. It's important to go and get it weighed at a truckstop or commercial scales to make sure you are not overweight too. Best to find a scale that weight all dour wheels but if you can't find one at least get front and back. Weigh it fully loaded with a full tank of gas and a full water tank. I also add five lbs for safety as many others do. Pressure is always measured cold or after sitting an hour.
Happy motoring.

Skip426 · 02-29-2016, 10:41 AM

The tires should be good , my question (s ) would be .
Do you have the correct load capacity for the Michelins at the 85 PSI, because , I think it's odd that dropping the pressure 10 PSI, yields the same capacity.

Are you chasing a handling issue or tire wear?
Have you weighed the coach loaded for travel ? Four corners is best.

You can never overlook the possibility that you're overloaded.

EDIT: and I see my slow typing has come up again , and someone with the same info has already posted.

Dave-Oh · 02-29-2016, 11:22 AM

It's all good! I will weigh at some point and yes, it's a handling issue (if you REALLY want to know, read the thread, "LOOSE KING PINS?"). The light truck/RV service department I used for alignment actually road-tested the rig and told me that the vibration I'm feeling is "all tires". He guaranteed that if I changed to Michelins, it would fix it. He's seen this forever and won't recommend Goodyears because of it. Oddly enough, the guy from the Wingfoot shop (where Goodyear sent me to REPLACE all the tires) told me that he's seen this a lot, too. They "just change brands, and don't have to come back again".

I'm ready to try it....

Mr_D · 02-29-2016, 11:36 AM

First off I see an incorrect statement when it's posted that:

Quote:

Max inflation on the GYs: 110 with 4540 lb capacity
Max inflation on the Michelins: 95 with a 4080 lb capacity

The pressure on the sidewall of a Michelin RV tire and many others is not the "Maximum" the tire should ever have (unlike car tires) it is the minimum to support the maximum rated carrying capacity of the tire.

From page 2 of the 06/07 Michelin RV Tire Guide:

Quote:

"If you look at the tire's sidewall, you'll see the maximum load capacity allowed for the size tire and load rating, and the minimum cold air inflation needed to carry the maximum load."

From page 6 of the GoodYear RV Tire and Care Guide:

Quote:

"How much air is enough?
The proper air inflation for your tires depends on how much your fully loaded RV or trailer weighs. Look at the sidewall of your RV tire and you’ll see the maximum load capacity for the tire size and load rating, as well as the minimum cold air inflation, needed to carry that maximum load."

From TOYO:

Quote:

Q: What are the consequences of inflating the tires to accommodate the actual loads?
A: If the inflation pressure corresponds to the actual tire load according to the tire manufacturer’s load and pressure table, the tire will be running at 100% of its rated load at that pressure. This practice may not provide sufficient safety margin. Any air pressure loss below the minimum required to carry the load can result in eventual tire failure.

But then they go ahead and publish a weight/pressure chart allowing lower pressure for RV's!!

From the August 2010 Motorhome Magazine "Tread Carefully" tire article:

Quote:

The maximum load capacity allowed for the size tire and load rating and the minimum cold air inflation needed to carry that maximum load are located on the tire’s sidewall.

Once a change is made to a different size/weight rating tire you will go by that tire manufacturers weight/pressure charts.

Dave-Oh · 02-29-2016, 01:48 PM

Thanx all!

I did look up the load capacities on the tire charts but just wanted to be sure I wasn't missing anything...basically that I won't be overloading the tires if I change. I appreciate everyone's advice and insights.

If I change, I'll carry the new brand's inflation/load chart in the rig and adjust air pressure accordingly.

Kahoona · 03-01-2016, 10:44 AM

Quote:

Originally Posted by Skip426

The tires should be good , my question (s ) would be .
Do you have the correct load capacity for the Michelins at the 85 PSI, because , I think it's odd that dropping the pressure 10 PSI, yields the same capacity.

Are you chasing a handling issue or tire wear?
Have you weighed the coach loaded for travel ? Four corners is best.

You can never overlook the possibility that you're overloaded.

EDIT: and I see my slow typing has come up again , and someone with the same info has already posted.

LOL Happens to me all of the time. I type either slowly or badly, my choice which. Our Coachmen came with nasty hard truck tires which were the tires which the tire pressures were set up for. When I changed to real comfy Goodyears the recommended pressure doped by quite a bit. My current Michelins are supposed to use 175 but being the careful sort I run them at 180. That leaves me some slack in case of changing conditions or the DW starting a rock collection and not telling me. You may chortle but it has happened. Just like in the Lucy movie.

Kahoona · 03-01-2016, 10:45 AM

Quote:

Originally Posted by Dave-Oh

Thanx all!

I did look up the load capacities on the tire charts but just wanted to be sure I wasn't missing anything...basically that I won't be overloading the tires if I change. I appreciate everyone's advice and insights.

If I change, I'll carry the new brand's inflation/load chart in the rig and adjust air pressure accordingly.

That is the best. I keep mine on my phone.