Tire Information Links

[Tom and Patty]

I thought that since we get so many questions on tires and inflation it would be good to post some links from the three major tire brands. All three majors have great information. Bridgestone has a great RV tire care page and Michelin has that great video "The Critical Factor"

Bridgestone
Bridgestone Load inflation tables rim size 17.5 and above
http://www.trucktires.com/bridgeston...Truck_Load.pdf
Bridgestone load inflation tables 15', 16", 16.5", 17", 18"
http://www.trucktires.com/bridgeston...Truck_Load.pdf
RV Owners Tire Care and Usage
Bridgestone Commercial Truck Tires

Michelin
RV Videos and Demos
Michelin North America RV Videos and Demos Page
Michelin load and inflation tables
Michelin North America RV Load & Inflation Tables

Goodyear
Weighing your RV
On The Wings of Goodyear | RV Tires - Weighing Your RV
Load inflation tables MH's and trailers
http://www.goodyear.com/rv/pdf/rv_inflation.pdf

Please feel free to add to the list. Maybe we can may this a sticky.

[DriVer]

Quote:

Originally Posted by Tom and Patty I thought that since we get so many questions on tires and inflation it would be good to post some links from the three major tire brands. All three majors have great information. Bridgestone has a great RV tire care page and Michelin has that great video "The Critical Factor"

Tom and Patty, √ Thanks for taking the time to do this, it's what iRV2 is all about!

[RV Wizard]

Yes, I agree. This will be a convenient way for our member to find out what tire pressure they need to run as well as other important information about their tires. Thank you.

[CARVAL Motorsports]

They are just about one in the same with Bridgestone, however, different pricing, different stamping, etc., so maybe Firestone should not be left out of the mix. I bought 8 new last year before our east coast trip, no problems to report with ride quality or steer, and they were available at a decent price.
Firestone Truck and Commercial Tires
Firestone Commercial Truck Tires

[Nick-B]

I have Toyo tires on my Coachmen and I know they are popular with other RVers so here is the link to their Load/Pressure info:
LOAD & INFLATION TABLES | Toyo Tires

[Tireman9]

Here are some other tire related links:


National Highway Traffic Safety Administration
Tire Safety

Rubber Manufacturers' Association
Tire Safety

Air Pressure, Temperature variation
Tire Rack

Passenger tire inflation w/video

The Tire & Rim Association. Where to buy Industry Standards books

GM view on tire safety

MasterCraft tire Education


GM on Nitrogen This Bulliten is from a Cadilac blog but it has the full text of the bulliten

[wirelessenab]

I run Sumitomo ST718 on my Discovery.

Here is the catalog, inflation table is on p.16 near the end of the catalog.

http://www.sumitomotire.com/assets/p...ck_Catalog.pdf

[Batman_777]

Excellent Document on General Tire Information:
http://www.trucktires.com/bridgeston...V_Brochure.pdf

Weight
Care
Inflation
Loading
Capacity
Aging
Repair
Protection
Dually
Rotation
Alignment

[Tom and Patty]

More good info. Thanks everyone for sharing.

[Tireman9]

We talk about knowing your real weights by corner but not everyone gets to large RV Rallies where RVSEF offers their services. Here is a link to CAT scales. Any certified scale will work for getting your RV weighed. You might find a local company if you check your phone book or try this link.

You should NOT adjust your inflation for each tire based on it's real load. Tire inflation affects both load carrying capability as well as vehicle handling (turning right forces should = turning left forces). You should have all tires on an axle at the same inflation +/- 1 psi which is easy to achieve with a digital inflation gauge.

Now knowing that all tires on an axle should have the same inflation we need to be sure no tire is overloaded. The procedure recommended by experienced tire design engineers is to:
1. Get the weights with the vehicle fully loaded (water, fuel, food, clothes, co-pilot, pets etc.)
2. Use a published Load & Inflation table. You should be able to find that info in this thread.
3. Look up the lowest inflation that has the load higher than yours.
4. Be sure to note that if you have Duals there are different load numbers.
5. That lowest inflation is your MINIMUM "Cold" inflation.
6. "Cold" inflation is measured at ambient, not in the sun and at least 3 or 4 hours after it was driven.
7. All tires leak air at about 1% - 3% per month. This is at the molecular level. Also cold tire pressure changes with ambient temperature at about 2% per 10 Degrees F. There is also an altitude effect, so to avoid having to inflate your tires every few days as you travel around, many recommend that you inflate your tires to 5 psi above your minimum. That way it will be longer before you have to add air.

Finally, If you discover you are a few (1 to 5) psi lower than you want to be, but have to drive a bit to get to high pressure air, simply make a note of the number of pounds you need to add for each tire. Drive the few miles at speeds lower than 50 and when you get to the location with air, again measure the now "Hot" pressure. Check your notes and add the number of pounds you want for each tire and add that plus 1 psi to the hot pressure to get your new inflation.
If you follow this procedure I think you will find that you are back to your desired +/- 1 psi cold the next moning.

Hope this helps.

[az bound]

Tireman9; This is the best inflation article I have ever seen. I have to wonder why manufacturers fail to show this iformation along with their charts. The key words that seems to be overlooked by many "minimum cold inflation".
Would you not agree that running a tire at minimim would be detrimental to tire life ?
Thanks very much for the information.

[WOODYDEL]

Michelin Fundamentals of tire Wear..and other info videos...
http://www.michelintruck.com/micheli...entalsofTireCD

[Tireman9]

Quote:

Originally Posted by az bound Tireman9; This is the best inflation article I have ever seen. I have to wonder why manufacturers fail to show this iformation along with their charts. The key words that seems to be overlooked by many "minimum cold inflation". Would you not agree that running a tire at minimim would be detrimental to tire life ? Thanks very much for the information.

The minimum is just that. If you set your tire to the minimum there are some instances where you will be overloaded 24 hours later (Temperature changes). Or on some vehicles simply putting five 200# people in the vehicle instead of two at 154# will result in overload as the manufacturer provided essentiLLY NO "RESERVE LOAD".

Sometimes "minimum" is established based on assumptions on how much stuff you put in your vehicle or how much people weigh. Placards and charts are just estimates. When there is data showing that over 50% of RVs have one or more component overloaded I can not understand why people complain when they have a tire failure due to overload and poor or no maintenance. They made a concious decision to not educate themselves about their RV but somehow want to blaim the tire mfg when the tire fails due to overload.
If there were really as many "defective" tires out there as some want to claim there would be many more recalls.
I saw an item this morning where NHTSA is starting an investigation because of 54 complaints out of 80,000 items having possible failure.

After 4 to 8 years usage I wonder if there are only 54 RVs that have had say a water pump or generator or refrig or someother part fail but I don't hear owners demanding better quality from RV manufacturers.

[FastEagle]

Quote:

Originally Posted by Tireman9 We talk about knowing your real weights by corner but not everyone gets to large RV Rallies where RVSEF offers their services. Here is a link to CAT scales. Any certified scale will work for getting your RV weighed. You might find a local company if you check your phone book or try this link. You should NOT adjust your inflation for each tire based on it's real load. Tire inflation affects both load carrying capability as well as vehicle handling (turning right forces should = turning left forces). You should have all tires on an axle at the same inflation +/- 1 psi which is easy to achieve with a digital inflation gauge. Now knowing that all tires on an axle should have the same inflation we need to be sure no tire is overloaded. The procedure recommended by experienced tire design engineers is to: 1. Get the weights with the vehicle fully loaded (water, fuel, food, clothes, co-pilot, pets etc.) 2. Use a published Load & Inflation table. You should be able to find that info in this thread. 3. Look up the lowest inflation that has the load higher than yours. 4. Be sure to note that if you have Duals there are different load numbers. 5. That lowest inflation is your MINIMUM "Cold" inflation. 6. "Cold" inflation is measured at ambient, not in the sun and at least 3 or 4 hours after it was driven. 7. All tires leak air at about 1% - 3% per month. This is at the molecular level. Also cold tire pressure changes with ambient temperature at about 2% per 10 Degrees F. There is also an altitude effect, so to avoid having to inflate your tires every few days as you travel around, many recommend that you inflate your tires to 5 psi above your minimum. That way it will be longer before you have to add air. Finally, If you discover you are a few (1 to 5) psi lower than you want to be, but have to drive a bit to get to high pressure air, simply make a note of the number of pounds you need to add for each tire. Drive the few miles at speeds lower than 50 and when you get to the location with air, again measure the now "Hot" pressure. Check your notes and add the number of pounds you want for each tire and add that plus 1 psi to the hot pressure to get your new inflation. If you follow this procedure I think you will find that you are back to your desired +/- 1 psi cold the next moning. Hope this helps.

Hi Tireman, FastEagle Here.


What is your basic explanation as to just how a tire manufacturers tire inflation table is supposed to be applied when used in conjunction with self propelled RV vehicles or RV trailer tires?

We see a lot of experts talking about the reserve load carrying ability tires are supposed to have. But we cannot find it in print. By using a load inflation table as you and many other highly knowledgeable people in the tire industry promote, we can end up with zero published reserves.

Here is a case I have specs for. Sorry it’s for an RV trailer but if helps demonstrate how most of the RV manufacturers view their responsibility when it comes to selecting tires.

An RV trailer with two 7000# axles is delivered to it’s new owner with four ST235/80R16E tires on those axles. The vehicle tire placard tells the owner to air those tires to 80 psi (matching the maximum amount shown on each tires sidewall) to obtain 3520# of load carrying ability from each of the tires. The vehicle manufacturer has satisfied his requirement to equal or exceed the DOT requirement for tires on those axles. The new owner has a total reserve load carrying capacity totaling 80#. I don’t care who made those tires. They are going to fail and early. My guess would be less than a year if the owner is loaded close to GVWR.

The bottom line here is when you tell us to use the load inflation tables as describe in your thread above you are placing us in the same condition the vehicle manufacturer has put the above owner in.

Knowledgeable tire people will say the Light Truck tire has a greater reserve than the Special Trailer tire but NOBODY will publish it as fact with figures. These same people say ST tires degrade faster than LT tires yet they fail just as frequently when used under equal conditions.

When reading through the major 2007 DOT rules changing document many of those giving inputs into the decision making process recommended that RV tires be required to have a minimum of 12-15% reserve load carrying capacity above the GAWR. The rules makers disagreed and left the industry as is until such time as new rules are discussed again.

I’m a firm believer in a large reserve, especially for the RV. I have an RV trailer and I keep tires on it that will always give me a 20% reserve.

FastEagle

p.s. Here is a little wrench for your gears.
When an RV trailer manufacturer puts tires rated at 3420# @ 80 psi on both ends of a 6000# axle and tells the new owner via the tire placard that that is his minimum recommended requirement, what is the owner to do when you tell him it’s OK to use the tire manufacturers load inflation table? According to the DOT the vehicle manufacturer sets the inflation pressures (using the information from the tire manufacturer) for the tires he has selected for that axle.