Maxxis ST tire speed rating

[whatsupchuck]

Maxxis website does not provide the speed rating for their ST225/75R15 8 or 10PR TL M8008 tires. I know some of y'all have them and would like to know what yours are rated at.

The last I was told was probably K which is only 68 MPH. I'm hoping they at least tested at L or M. 65 MPH in Texas on interstate will get you hit in the rear.

Thanks.

[Retired JSO]

This site shows the new MAXXIS rating as Qhttps://www.onlinetires.com/search/vehicle/tires/maxxis/6026/all_prices/all_sizes/all_tires/all_speeds/page_1.html. According to the follow up i see that a Q is 99 mph. I don't have MAXXIS but our new trailer has ST 225 15 Tires and the sidewall has 75 mph on it.

[whatsupchuck]

The official site for Maxxis seems to not want anyone to know. I'll check the one you mentioned if I can get IE to work.

www.maxxis.com will not show speed ratings and mumbles around driving safely.

[whatsupchuck]

I had to restart my computer as Internet Expl. got stupider!

I did check your recommended site and that gives me hope. Checking the Maxxis site, I guess they don't want it spread. This gives me hope along with good reviews by folks here who have Maxxis. Speed rating of 99 is way above what I need, but, good to know.

My present factory tires are the famous Castle Rock from the same supplier that blessed me with light rims / Lions Head. Contacting them several months ago, I could get no response on the pressure rating of the rims.

I am also glad to get the info. on price on the site you provided. Now I can ask Discount Tire why they want so much for the same tire. HMMMM!

[Airdale]

ST tires without speed letters on their sidewalls or the actual speed rating on the sidewall are rated by the TRA at 65 MPH. Some manufacturers (Goodyear & Power King) have authorized their ST tires to go 75 MPH with a 10 psi increase in inflation above the maximum listed on their sidewalls without an increase in load capacity.However, those tires are made in China and will soon have speed ratings on their sidewalls.

[TomStacey616]

Per Amazon, M8008's, 10 and 8 ply have a speed rating "R" which is 106mph, not that anyone would pull that fast....

[OldCoot]

Originally Posted by whatsupchuck

...65 MPH in Texas on interstate will get you hit in the rear.

Thanks.

Must be a lot of blind people driving in Texas if they can't see a 5er or TT.

[hbillsmith]

It's not the speed rating that governs trailer tow speed. It's the load rating. Maxxis tires are load rate E or less and that means 65mph. Maxxis requires 80psi cold pressure to support even the 65mph. You can increase PSI by 10% to get higher speeds as long as it doesn't exceed the tire manufacturers maximum PSI. Maxxis 8008 E rated have a max psi of 80psi. If you want to go faster, you'll need a tire that has a higher load rating (F and G like Sailun can be found). But keep in mind, your existing wheels may not support the higher pressure required to go to 110psi and it's 110psi that's required to go up to 75mph.

Of course, you can choose to change out both your wheels and your tires as long as your model trailer has enough clearance and as long as the tire you choose has the same or better carry weight capacity.

[Witch Doctor]

Originally Posted by whatsupchuck

I had to restart my computer as Internet Expl. got stupider!

I did check your recommended site and that gives me hope. Checking the Maxxis site, I guess they don't want it spread. This gives me hope along with good reviews by folks here who have Maxxis. Speed rating of 99 is way above what I need, but, good to know.

My present factory tires are the famous Castle Rock from the same supplier that blessed me with light rims / Lions Head. Contacting them several months ago, I could get no response on the pressure rating of the rims.

I am also glad to get the info. on price on the site you provided. Now I can ask Discount Tire why they want so much for the same tire. HMMMM!

I think what you are missing here is that the speed rating is only for test speeds. They are not the recommended speed such as ST which are at 65 mph. Also GY Marathons are the only tire company that I know of that shows that in print that you can go over by adding PSI to the tire. Also they even go as far as to say that the tire still needs to be able to carry the weight. Tire Rack site has a whole page on how they come up with the speed ratings. The only thing per their site says " Well in general, a higher speed rating will result in better car handling" That's on there web site info center under speed rating. From letter "B" to "Z" with the test speeds only not recommended speeds....Speed ratings go from 31mph for "B" to 149mph for "Z" rated......

[CraigBean7672]

I just changed from LRC China Bombs to LRD Maxxis ST225/75R15.

I called Lionshead and they verbally said the rim is okay for it, that is, going up one load range C --> D. I will be running more air but not more weight.

Going from 50psi to 65psi cold max inflation but will probably run at 62psi

Jumping from load range C to E was discouraged from our tire expert on this forum since the rim is rated only for C and running an E rated tire at C air pressure will generate undesirable heat.

O and back to your original question, I followed the speed rating thing and confirmed what you saw there's no specific rating on the tire itself and website is vague. Not sure where Amazon and Online are getting their info. Anywho, recent article published by our forum's tire expert/engineer recently discussed the tire rating test conducted by manufacturer's and it left me thinking it is too static of a test to really rely on.

Whatever the rating is, it could build heat running it at a faster speed continuously.

For me, Maxxis is one of the best ST tires out there, I also went up one load rating, I use a TPMS, and don't speed.

[Witch Doctor]

Originally Posted by CraigBean7672

I just changed from LRC China Bombs to LRD Maxxis ST225/75R15.

I called Lionshead and they verbally said the rim is okay for it, that is, going up one load range C --> D. I will be running more air but not more weight.

Going from 50psi to 65psi cold max inflation but will probably run at 62psi

Jumping from load range C to E was discouraged from our tire expert on this forum since the rim is rated only for C and running an E rated tire at C air pressure will generate undesirable heat.

O and back to your original question, I followed the speed rating thing and confirmed what you saw there's no specific rating on the tire itself and website is vague. Not sure where Amazon and Online are getting their info. Anywho, recent article published by our forum's tire expert/engineer recently discussed the tire rating test conducted by manufacturer's and it left me thinking it is too static of a test to really rely on.

Whatever the rating is, it could build heat running it at a faster speed continuously.

For me, Maxxis is one of the best ST tires out there, I also went up one load rating, I use a TPMS, and don't speed.

I have the exact same unit as yours, I also went up to "D" rated the same tire as you. I forgot what dealer but they where located in Mayberry NC, wanted to put "E" on my rims, I told him I seen the stamp on the inside and they were rated for 65 PSI. for us to go to "E" the rim would need a stamp of 80 PSI not the 65 PSI that it has on it. I can't really believe that FR put "C" rated on the trailer. Just barely carried the load, but they where legal....

[GreenImp]

Originally Posted by Airdale

ST tires without speed letters on their sidewalls or the actual speed rating on the sidewall are rated by the TRA at 65 MPH. Some manufacturers (Goodyear & Power King) have authorized their ST tires to go 75 MPH with a 10 psi increase in inflation above the maximum listed on their sidewalls without an increase in load capacity.However, those tires are made in China and will soon have speed ratings on their sidewalls.

I believe this is an error. The way I understood Goodyear's publication is that in order to increase the speed by 10 MPH, the cold PSI must be increased by 10 over the "recommended PSI based on tire load"....not by increasing the PSI by 10 over the "maximum PSI listed on the sidewall". I don't have any knowledge of Power King's position on this.

Tirerack has a copy of Goodyear's publication posted here...
https://www.tirerack.com/images/tire...plications.pdf

[Moose509]

This site shows the speed ratting and load ratings for MASSIS tires.Maxxis Automotive Tire School | Maxxis Tires USA

[Moose509]

LOAD/INFLATION INFORMATION FOR ST METRIC TRAILER TIRES
TIRE LOAD LIMITS (LBS) AT VARIOUS COLD INFLATION PRESSURES (PSI)
FOR ST TRAILER TIRES USED IN NORMAL HIGHWAY SERVICE

Tire Size Inflation Pressure - PSI
25 30 35 40 45 50 55 60 65 70 75 80
ST175/80R13 905 1000 1100(B) 1190 1270 1360(C)
ST185/80R13 990 1100 1200(B) 1300 1400 1480(C)
ST205/75R14 1170 1300 1430(B) 1530 1640 1760(C)
ST215/75R14 1270 1410 1520(B) 1660 1790 1870(C)
ST205/75R15 1220 1360 1480(B) 1610 1720 1820(C) 1940 2040 2150(D)
ST225/75R15 1430 1600 1760(B) 1880 2020 2150(C) 2270 2380 2540(D) 2620 2720 2830(E)
ST235/80R16 1720 1920 2090(B) 2270 2430 2600(C) 2730 2870 3000(D) 3130 3260 3420(E)

[Moose509]

Trailer Tire Load/Inflation Chart | Maxxis Tires USA

This chart shows what weight / psi relationship.

Good Luck

[PhoneDude 8289]

Originally Posted by whatsupchuck

Maxxis website does not provide the speed rating for their ST225/75R15 8 or 10PR TL M8008 tires. I know some of y'all have them and would like to know what yours are rated at.

The last I was told was probably K which is only 68 MPH. I'm hoping they at least tested at L or M. 65 MPH in Texas on interstate will get you hit in the rear.

Thanks.

I live and travel allot in Texas. I travel the highways with my 5th wheel my speed locked at 63 MPH and have never come close to getting hit in the rear or any place else. I have been riding on Maxxis M8008's "E" rated @ 75 PSI for over a year. Stamped on each tire is 65 MPH, I'm good with that.

[OldBob]

Originally Posted by OldCoot

Must be a lot of blind people driving in Texas if they can't see a 5er or TT.

I agree. I set the cruise control for 62 mph and that's as fast as I tow. So far no one has hit me from behind and I've towed in just about every state.

[WolfWhistle]

I've noticed the slower I go the more waves I get from folks passing me. DW wonders why they wave with a pronounced finger... told her they're telling me I'm number 1 in their book
WW

[Butch Wilson]

Lordy, glad I was not on this forum last year. I pulled a 8 year old used pop-up, original tires on a 10,000 mile shakedown trip. I found myself at one point on I-25 in Wyoming doing 90mph . Pulled at 75mph out of Barstow Ca across the desert. Now I am afraid at 60 mph ! I guess ignorance is bliss Is a true statement .

[Airdale]

Originally Posted by GreenImp

I believe this is an error. The way I understood Goodyear's publication is that in order to increase the speed by 10 MPH, the cold PSI must be increased by 10 over the "recommended PSI based on tire load"....not by increasing the PSI by 10 over the "maximum PSI listed on the sidewall". I don't have any knowledge of Power King's position on this.

Tirerack has a copy of Goodyear's publication posted here...
https://www.tirerack.com/images/tire...plications.pdf

This is a direct quote from the Tire Rack. It's how they interpret Goodyear & Power King PDFs excess speed for ST tires.

"Unless assigned a specific Speed Rating, industry standards dictate tires with the ST designation are speed rated to 65 mph (104 km/h) under normal inflation and load conditions.

However, Goodyear Marathon and Power King Towmax STR tires featuring the ST size designation may be used at speeds between 66 and 75 mph (106 and 121 km/h) by increasing their cold inflation pressure by 10 psi (69 kPa) above the recommended pressure for the rated maximum load.

Do not exceed the wheel's maximum rated pressure. If the maximum pressure for the wheel prohibits the increase of air pressure, then maximum speed must be restricted to 65 mph (104 km/h).

The cold inflation pressure must not exceed 10 psi (69 kPa) beyond the inflation specified for the maximum load of the tire.

Increasing the inflation pressure by 10 psi (69 kPa) does not provide any additional load carrying capacity."

On edit, a footnote; All ST and LT tires are allowed to have a 10 psi increase in inflation pressure above what is displayed on their sidewalls. It's seldom used but is an option any tire manufacturer can use and explains the use by Goodyear & Power King in this situation.