Maxxis Tires Speed Rating - Mfg's Statement

[CurtPutnam]

Our M8008 ST radials have a "Q" speed rating. However, according to the Tire & Rim Association, the U.S. tire industry authority, inflation pressures and load specifications in general for any ST Radial trailer tires, regardless of the tire manufacturer, are designed and rated at 65 MPH. However, if the speed is higher than 65 MPH, the pressure and load need to be adjusted according to the following guidelines:
From 66 to 75 MPH - the tire inflation pressure needs to increase 10 PSI (not to exceed the maximum PSI the tire is rated for) and load should be reduced by 10%

From 76 to 85 MPH - the tire inflation pressure needs to increase 10 PSI (not to exceed the maximum PSI tire is rated for) and load should be reduced by 10%

Please refer to our web site for detailed dimensions and specifications on our M8008.

For information purposes only, The Maxxis M8008 ST Trailer Tire is manufactured in our company owned state-of-the-art factory in Thailand.

[EdJunior]

Interesting. I still only tow my 5th wheel at 65mph. Well, sometimes I creep up to 67 or 68, but just haven't found a need to go faster. 65 is plenty fast when you're towing a 11,000 pound trailer behind a 7,500 pound truck.

[2Evil4U]

So I'm good to 85. Cool.

[Wileykid]

Originally Posted by CurtPutnam

Our M8008 ST radials have a "Q" speed rating. However, according to the Tire & Rim Association, the U.S. tire industry authority, inflation pressures and load specifications in general for any ST Radial trailer tires, regardless of the tire manufacturer, are designed and rated at 65 MPH. However, if the speed is higher than 65 MPH, the pressure and load need to be adjusted according to the following guidelines:
From 66 to 75 MPH - the tire inflation pressure needs to increase 10 PSI (not to exceed the maximum PSI the tire is rated for) and load should be reduced by 10%

From 76 to 85 MPH - the tire inflation pressure needs to increase 10 PSI (not to exceed the maximum PSI tire is rated for) and load should be reduced by 10%

Please refer to our web site for detailed dimensions and specifications on our M8008.

For information purposes only, The Maxxis M8008 ST Trailer Tire is manufactured in our company owned state-of-the-art factory in Thailand.

First, my towing speed is 65 mph.

From this statement, which I think is now a bit outdated with the newer tires, with my Goodyear Endurance tires, if I wanted to do say 85 mph (rated 87 mph) I need to reduce my load 20%. Yet if you read what the Goodyear general manager said in this article (http://www.tirebusiness.com/article/...plate=printart), he clearly implies that the tires are designed for carrying full load at the speed the tire is rated for. That the tire was designed for both consumer and commercial use.

Maybe the Maxxis needs the reduction, but from what I have read, at least Goodyear is not saying you need to.

Mark

[goduc]

Thats why I went with Carlisle HD's. 81 mph, no questions asked. No I don't tow at 81 mph, but I do tow at 65 mph. And will tow at 70 mph when out in the boonies.

[CurtPutnam]

I asked Maxxis what the speed rating was. They said "Q" and then added the caveats required by the US Tire & Rim Association. Note that the caveats are not manufacturer specific. The Maxxis tires are good to 85 under the same conditions as everyone else.

So if everyone follows the "rules", all tires need to reduce load & increase pressure to get to 85 mph. What this means to your driving habits is up to you. Me? I'll stick to 65 - 70 on smooth & straight freeways. Might could let the speed creep up a little on a good road devoid of traffic. But 9,000 lbs tied to the rear is still a daunting thing to consider when things get sideways.

[Filterman]

Originally Posted by CurtPutnam

I asked Maxxis what the speed rating was. They said "Q" and then added the caveats required by the US Tire & Rim Association. Note that the caveats are not manufacturer specific. The Maxxis tires are good to 85 under the same conditions as everyone else.

So if everyone follows the "rules", all tires need to reduce load & increase pressure to get to 85 mph. What this means to your driving habits is up to you. Me? I'll stick to 65 - 70 on smooth & straight freeways. Might could let the speed creep up a little on a good road devoid of traffic. But 9,000 lbs tied to the rear is still a daunting thing to consider when things get sideways.

I am definitely with you! Tow a 28RKS Wildcat that’s about 10000GW ready to roll. Use Goodyear Marathons at pretty close to max pressure at all times and have never had a blowout on pavement, gravel hot or cold. Max tow speed 100KPH EVER. .....well ok maybe roll out on a wide open hill to 103-4 but speed when towing heavy trailers has never made sense to me. We are not full timers but about 1/2 timers and in our fifth season with these Marathons.30 years of towing!

[Tireman9]

Originally Posted by Wileykid

First, my towing speed is 65 mph.

From this statement, which I think is now a bit outdated with the newer tires, with my Goodyear Endurance tires, if I wanted to do say 85 mph (rated 87 mph) I need to reduce my load 20%. Yet if you read what the Goodyear general manager said in this article (http://www.tirebusiness.com/article/...plate=printart), he clearly implies that the tires are designed for carrying full load at the speed the tire is rated for. That the tire was designed for both consumer and commercial use.

Maybe the Maxxis needs the reduction, but from what I have read, at least Goodyear is not saying you need to.

Mark

Have to wonder what "magic" rubber and construction features they put in their ST tires such that they are 10% to 20% better than any of the GY LT tires.
Suggest you compare your ST tire load capacity with an identical size LT load capacity from Gy.

Don't you think that if GY had some super construction features they would have that stuf in all their LT tires to allow them to claim better load capacity?

[Wileykid]

Originally Posted by Tireman9

Have to wonder what "magic" rubber and construction features they put in their ST tires such that they are 10% to 20% better than any of the GY LT tires.
Suggest you compare your ST tire load capacity with an identical size LT load capacity from Gy.

Don't you think that if GY had some super construction features they would have that stuf in all their LT tires to allow them to claim better load capacity?

Look, I don't even scratch the surface of your knowledge of tires. Nor do I profess to have the knowledge of the "magic" that they put in one tire or another. I can only go on what the manufacturer of the tire says the tire will do (we are not talking China bombs).

I am always up for new knowledge. Please direct me to where the information is that shows the manufacturer is wrong. That the load they say the tire (ST not LT) is capable of is actually mis-information.

Mark

[acadianbob]

Originally Posted by goduc

Thats why I went with Carlisle HD's. 81 mph, no questions asked. No I don't tow at 81 mph, but I do tow at 65 mph. And will tow at 70 mph when out in the boonies.

Me too!! I tow at 62 mph but like the extra margin on the downhills.

[Super 8]

Tire Industry must be changing to comply with the higher speed demands of ST tires. I just ordered 4 new ST Carlisle's for a smaller trailer that I own with a "R" speed rating, 106mph.

[Airdale]

Originally Posted by Wileykid

Look, I don't even scratch the surface of your knowledge of tires. Nor do I profess to have the knowledge of the "magic" that they put in one tire or another. I can only go on what the manufacturer of the tire says the tire will do (we are not talking China bombs).

I am always up for new knowledge. Please direct me to where the information is that shows the manufacturer is wrong. That the load they say the tire (ST not LT) is capable of is actually mis-information.

Mark

You hit the nail right on the head. If it's not on the tire it's not official. And, have you seen original equipment tires that have a vehicle manufacturer recommended cold inflation pressure below the psi figure on the tire's sidewall.

Maxxis does not get any tariff incentives so they are not threatened by the customs people to have speed letters on their tires. Maybe Maxxis cannot get more speed to pass the tests required for upping their 65 MPH limit without upgrading their building materials???

[kamper00]

Originally Posted by EdJunior

Interesting. I still only tow my 5th wheel at 65mph. Well, sometimes I creep up to 67 or 68, but just haven't found a need to go faster. 65 is plenty fast when you're towing a 11,000 pound trailer behind a 7,500 pound truck.

X2

[Mad Cow]

Originally Posted by Airdale

You hit the nail right on the head. If it's not on the tire it's not official. And, have you seen original equipment tires that have a vehicle manufacturer recommended cold inflation pressure below the psi figure on the tire's sidewall.

Maxxis does not get any tariff incentives so they are not threatened by the customs people to have speed letters on their tires. Maybe Maxxis cannot get more speed to pass the tests required for upping their 65 MPH limit without upgrading their building materials???

Rarely is any tire needing to run at max pressure on the side wall of the tire. That is the pressure for the max loading on the tire, and it is not common for folks to have a a gross that is the max the tire was designed to run.

On my semi truck tires, the max on the sidewall is 120 PSI. But The recommended pressure from the tire maker based on the max load of my axles is 95 PSI. I have averaged 400,000 miles on drive tires following the guidelines from the tire OEM.

Same thing for the BFG KO2's on my 3/4 ton pickup. The vehicle OEM recommended pressure is when the pickup is at max gross and the brand and type of tire from the factory. I ignore that. I have a chart from BFG for the exact tire I am running that shows recommended pressure based on weight on the axles.

If one wants, they can usually pry a recommended load pressure chart from the tire OEM for the particular tire they are running and stick to it. In my experience, following the guides makes for better handling, braking, and tire wear.

But everyone seems to know more than the folks who actually did the R&D on the tire.

[Airdale]

Originally Posted by Mad Cow

Rarely is any tire needing to run at max pressure on the side wall of the tire. That is the pressure for the max loading on the tire, and it is not common for folks to have a a gross that is the max the tire was designed to run.

On my semi truck tires, the max on the sidewall is 120 PSI. But The recommended pressure from the tire maker based on the max load of my axles is 95 PSI. I have averaged 400,000 miles on drive tires following the guidelines from the tire OEM.

Same thing for the BFG KO2's on my 3/4 ton pickup. The vehicle OEM recommended pressure is when the pickup is at max gross and the brand and type of tire from the factory. I ignore that. I have a chart from BFG for the exact tire I am running that shows recommended pressure based on weight on the axles.

If one wants, they can usually pry a recommended load pressure chart from the tire OEM for the particular tire they are running and stick to it. In my experience, following the guides makes for better handling, braking, and tire wear.

But everyone seems to know more than the folks who actually did the R&D on the tire.

R&D on most of our tires are a collaboration between the tire builder and the builder of the vehicle they are to be fitted to. In that combined industry, the vehicle manufacturer has the sole responsibility for recommended tire inflation pressures. Tire inflation charts/tables are provided by the tire manufacturer for a reference to insure the recommendations are accurate.

Fitments for automotive vehicles differ slightly from RV trailer tire fitments. Just like any other DOT certified tire they are designed to be inflated to the maximum amount displayed on their sidewalls.

Larger tires fitted to commercial vehicles come under a completely different set of rules and are without specific inflation regulations. Their primary rule is to be inflated - minimum - to the load carried, as that is the minimum the regulations allow. However, commercially designed tires, when fitted to vehicles built under the FMVSS standards, must adhere to those standards.

Recommended tire inflation pressures are an industry wide standard. Any retailer or tire installer will adhere to those pressures unless they are just not properly trained. For safety purposes, those cold recommendations are considered minimum.

As an owner and operator of your vehicles your views may differ from established standards. In most situations you are free to do as you see fit. And it may work for you. But, remember, you should not link all of your vehicle's tire inflation pressures to a single factor. A pick-up truck's recommended inflation pressures were set to the truck's normal load with reserves to cover it's maximum load. A RV trailer's tire's recommended inflation pressures are set to carry the trailer's maximum load.

[Mad Cow]

That would be somewhat true of the tire that comes on the trailer from the factory. That has no relevance to an after market tire purchase in which tires are for specific ratings, not specific trailer brands. Differing brands of trailer tires, meant for similar uses, do not always have the same inflation recommendations from the tire maker.

[Airdale]

Originally Posted by Mad Cow

That would be somewhat true of the tire that comes on the trailer from the factory. That has no relevance to an after market tire purchase in which tires are for specific ratings, not specific trailer brands. Differing brands of trailer tires, meant for similar uses, do not always have the same inflation recommendations from the tire maker.

All tires of the same design (ST - LT) - (some bias plys may differ from radials of the same size) - and size designation, use identical tire inflation charts.

Industry standards require replacement tires with different inflation charts, to have their new inflation pressures set at a psi setting that will equal the load capacity the OE tires provided on the vehicle's tire labeling.

[goduc]

Originally Posted by Airdale

All tires of the same design (ST - LT) - (some bias plys may differ from radials of the same size) - and size designation, use identical tire inflation charts.

Industry standards require replacement tires with different inflation charts, to have their new inflation pressures set at a psi setting that will equal the load capacity the OE tires provided on the vehicle's tire labeling.

x2

[Wileykid]

For me, this all comes down to a simple rules for me. Run the tire at max cold pressure and you should be within all safety margins as long as you keep the speed and weight within what is on the tire. You do not have to reduce max load beyond "x" speed unless the manufacturer has otherwise stated it on the side of the tire.

Now, with a chart provided by the manufacturer, you can run a reduced tire pressure at a lower load, and have a more comfortable ride, but it doesn't mean that you need to do that.

For me, when I am towing, I just keep everything at max cold PSI and not worry about it. If I am at max, 500, or a 1000 pounds under max trailer weight, who cares. And I tow at 65 mph, but I also know I could drive up to 87 mph and still be good.

If what I have said is wrong, please correct me. But not with anecdotal evidence.

Mark

[Mad Cow]

It isn't so much about a comfortable ride as it is effectiveness. A tire overinflated for the load will hydroplane more quickly and there is also a reduction in effective braking capability. It could also be argued that cornering ability is diminished with over inflated tires. There needs to be the proper "foot print" of the tire on the road surface, and overinflation for the load negatively affects that foot print.

Over 5 million documented miles of actual driving over a major portion of the N. American continent, and many more undocumented, have taught me a few things about tires.