ST Tires .vs. LT Truck tires

[klsrv]

ST tires are rated for 65mph. Has anyone put LT truck tires on a 26RLS to drive a little above 65 mph? - thanks

[Nighthawk 96]

Goodyear PSB #2011-13 states in part

"Special Trailer (“ST”) Tires
Goodyear Marathon trailer tires are widely used in a variety of towable trailer applications and are designed and branded as “ST” (Special Trailer) tires.

• Industry standards dictate that tires with the ST designation are speed rated at 65 MPH (104 km/h) under normal inflation and load conditions.

• Based on these industry standards, if tires with the ST designation are used at speeds between 66 and 75 mph (106 km/h and 121 km/h), it is necessary to increase the cold inflation pressure by 10 psi (69 kPa) above the recommended pressure for the rated maximum load.

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

o Do not exceed the maximum pressure for the wheel.

o If the maximum pressure for the wheel prohibits the increase of air pressure, then the maximum speed must be restricted to 65 mph (104 km/h).

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

I personally don't like to go faster than 65 mps.

[DocBrown]

I can't say that I have the same trailer, but I can tell you that lots of folks have done this with large trailers. I'm sure some here have. Some swear by it, some say its a waste of time. There are pluses and minuses to using LTs on trailers. This has been discussed in depth on rv.net. From what I've been able to glean over the years that this boils down largely to personal preference and what people have a comfort level for.

[RVer-Bill]

I don't know if this is correct, but I remember reading a few years ago that ST tires are designed with sidewalls that allow the tires to flex during turning. This is because of the dual axles and one tire being pushed inward and the other outward. Truck tires have more rigid sidewalls. I don't know what this impacts or stresses. Perhaps someone else can shed light on this.

[wwsmith111]

ST tires have firmer sidewalls than LT tires to control sway from the trailer.

[Seann45]

Ya wanna go faster than 65 towing a house with your family in the vehicle? Have you thought about upgrading your brakes to slow that freight train down? I am really not trying to be negative BUT.. I dont like reading about another RVer dieing or in a horrific crash on the highway...

[edatlanta]

X2 Seann.

[cekkk]

X3!

[DocBrown]

Lots of assuming going on here! Since the OP said "a little above 65", I'm giving him the benefit of the doubt that he's not suggesting doing 75.

[Rustic Eagle]

Might be a good time to Welcome the OP to JOF!

Originally Posted by DocBrown

Lots of assuming going on here! Since the OP said "a little above 65", I'm giving him the benefit of the doubt that he's not suggesting doing 75.

I agree.

Bob

[spoon059]

The speed police on this forum...?

When I bought my Carlisle Radial Trail RH tires, I believe the specs advised that the load rating diminishes above 65 mph. It doesn't state that you CAN'T go above 65, just that the load rating isn't as high at those higher speeds. On my current trailer, my D rated tires have about 50% reserve (I'm half the weight they are rated for). I figure if I get to 70 mph for an hour or two on the freeway, I'm okay.

Generally my wallet can't afford to pay for the fuel consumption above 65 or 67 mph...

That being said, LT tires should do just fine in place of ST tires. The only concern is that ST tires are designed to flex a little more when backing. You will scrub your LT tires more backing. I highly doubt you will wear through your tread on a tire on a trailer though. I've never replaced trailer tires due to overuse. They always get replaced due to age LOOOOOOOOOOOOOOOOONG before they are worn down.

[clutch]

I am not the speed police but the posted truck speed is the legal speed limit in most states for ANY vehicle towing a trailer of any kind. Our last trailer was a 5er with 16in wheels and it had 10 ply LT tires and they worked just fine. Our smaller 24 ft trailer needed new tires this summer and I had ST tires installed.

[spoon059]

I95 down in the southern states is a 70 mph roadway for all vehicles. Obviously you can drive below 70 (I think the minimum speed limit is 20 below the max), but you can legally tow at 70 mph.

[cekkk]

Originally Posted by spoon059

I95 down in the southern states is a 70 mph roadway for all vehicles. Obviously you can drive below 70 (I think the minimum speed limit is 20 below the max), but you can legally tow at 70 mph.

And it's 75 on most western Interstates. Legally, sure. Safely? Most of us are not professional drivers. My DW was, 35 years, and with a perfect safety record. I was taught by a professional driver and have a record that reflects that. Neither of us would run our 20,000 pounds of rig over 65. As it happens, 62 is the trucks sweet spot.

[SmokerBill]

I've done my share of driving 65+ MPH, but finally realized that the trip is just as much, if not more, fun as the destination. My original Goodyear Marathons (USA made) did well at the higher speeds, never leaked a drop of air, and were replaced (with the steel belts showing on a couple of tires) at 30K miles of use.

I have new Marathons now (probably China made) and after 10K they look great. But now I drive 55-60 most of the time, mainly because it's much more relaxing. I can enjoy the scenery, and I definitely feel safer.

The safety issue of going fast is only a small part about having a blowout. It's mostly about being able to slow down quickly when the unexpected situation raises it's ugly head. And believe me, that monster's head pops up every now and then. You never know when.

I almost ran into a herd of black angus cattle in Utah one rainy night. I was going only 30 MPH, but black cows are nearly invisible on the road when it's dark and rainy. My emergency stop put me within 10 feet of the cows when all was said and done. My heart was beating like a drum. Just saying, stuff happens.

[spoon059]

Originally Posted by cekkk

And it's 75 on most western Interstates. Legally, sure. Safely? Most of us are not professional drivers.

With all due respect, because I don't want this thread turning into a standard rv.net thread...

Just because you may not want to travel at 75 mph shouldn't preclude someone else from driving at 75 mph.

Speed, in and of itself, is not a great marker for safety, yet it is the #1 variable thrown out there. Obviously, the faster you go the faster you need to react. I am 34 years old. My reaction time is significantly greater than someone 68 years old. My 62 mph is safer than his 62 mph. My rig going down the road is less than 12,000 lbs with truck and trailer. My faster reaction time plus a lighter load makes me able to stop quicker and change lanes safer. The 68 year old with a 40,000 lbs Newmar pulling a 5000 lbs car with a slower reaction time is going to take a LOT longer to slow down or change lanes. Making a gross statement about a specific speed isn't logical. For the record, I think the Newmar has much higher speed ratings on their tires than my 6,000 lbs trailer...

Following proper driving habits, knowing where I have a safe lane to change at all times, scanning the road ahead of me and ahead of the driver in front of me, keeping a safe traveling distance, driving to the conditions of the roadway and maintaining a safe tow rig are all more important to me than some arbitrary number.

If 62 is safer than 70, than 55 is safer than 62, than 45 is safer than 55, than 35 is safer than 45, than 25 is safer than 35, that 15 is safer than 25. Any slower and its not RV'ing, its owning a vacation condo. Even then, you have to drive or fly to get there... so maybe its not safer to have a vacation condo. Better just stay in the house. Even then, might slip in the bathtub, so I better lay in bed. Even then I might get painful bed sores... now what do I do?

As I stated, I tend to drive around 67 mph. That isn't so slow on 70 mph highways as to create a hazard for other drivers, yet isn't so fast to horribly ruin my gas mileage. I am 34 years old, not retired and have limited time for vacations. I prefer to spend my lake weekend at the lake... not driving there. At times my speed can creep up to 70 or 75 mph for an hour or two. So be it.

LT tires have a higher speed rating. Buying ST tires with a much higher weight rating than you need can also allow you to exceed the 60 mph limit on ST tires... but read literature on your specific tire before you attempt it.

[cekkk]

Originally Posted by spoon059

With all due respect, because I don't want this thread turning into a standard rv.net thread...

Just because you may not want to travel at 75 mph shouldn't preclude someone else from driving at 75 mph.

Speed, in and of itself, is not a great marker for safety, yet it is the #1 variable thrown out there. Obviously, the faster you go the faster you need to react. I am 34 years old. My reaction time is significantly greater than someone 68 years old. My 62 mph is safer than his 62 mph. My rig going down the road is less than 12,000 lbs with truck and trailer. My faster reaction time plus a lighter load makes me able to stop quicker and change lanes safer. The 68 year old with a 40,000 lbs Newmar pulling a 5000 lbs car with a slower reaction time is going to take a LOT longer to slow down or change lanes. Making a gross statement about a specific speed isn't logical. For the record, I think the Newmar has much higher speed ratings on their tires than my 6,000 lbs trailer...

Following proper driving habits, knowing where I have a safe lane to change at all times, scanning the road ahead of me and ahead of the driver in front of me, keeping a safe traveling distance, driving to the conditions of the roadway and maintaining a safe tow rig are all more important to me than some arbitrary number.

If 62 is safer than 70, than 55 is safer than 62, than 45 is safer than 55, than 35 is safer than 45, than 25 is safer than 35, that 15 is safer than 25. Any slower and its not RV'ing, its owning a vacation condo. Even then, you have to drive or fly to get there... so maybe its not safer to have a vacation condo. Better just stay in the house. Even then, might slip in the bathtub, so I better lay in bed. Even then I might get painful bed sores... now what do I do?

As I stated, I tend to drive around 67 mph. That isn't so slow on 70 mph highways as to create a hazard for other drivers, yet isn't so fast to horribly ruin my gas mileage. I am 34 years old, not retired and have limited time for vacations. I prefer to spend my lake weekend at the lake... not driving there. At times my speed can creep up to 70 or 75 mph for an hour or two. So be it.

LT tires have a higher speed rating. Buying ST tires with a much higher weight rating than you need can also allow you to exceed the 60 mph limit on ST tires... but read literature on your specific tire before you attempt it.

Okay, you've convinced...you. I guess you're right, others can do as they please. And they do. I've dug several out of their wrecks. Next to booze, the next primary factor was speed. Teens have great reflexes. Somehow, that doesn't seem to be a major factor in their driving records. Oh. Yes it does!

There is so much more involved in avoiding an accident than reaction time. The difference between yours and mine, at more than double your age, may be 25 feet. The primary difference would be whether you know if you can change lanes, right or left, enough to minimize or avoid collision, or do you have to check your mirrors for the first time in ten minutes. There are a multitude of factors that are subject to your training and experience. And judgment!

No offense intended here, but your reply was so long it begged a response. Be safe.

[emjayuu]

So you get in 10 miles more per hour with accepting large risk to you and other drivers on the road. Slowing down isn't really such a huge impact to "spending time at the lake vs getting there" in my opinion.

[spoon059]

Originally Posted by cekkk

There is so much more involved in avoiding an accident than reaction time.

There are a multitude of factors that are subject to your training and experience. And judgment!

No offense intended here, but your reply was so long it begged a response. Be safe.

That was exactly MY point as well. There are many factors that determine how safe one is. Your argument seemed to be that excessive speed was unsafe. I disagree. You can be unsafe at 35 mph too. If you aren't a safe driver, if you aren't prepared to take evasive action, if you aren't scanning the road ahead of you, if your rig isn't properly set up, if you are distracted, if you are tired... any one of those things is dangerous.

My argument is simply this, some people can be safer drivers at higher than 62 mph because they are paying attention, scanning the road, good drivers and aren't distracted. Some people are horrible drivers, even at 55 mph. Speed isn't the sole issue.

No offense taken at all. We are all in the same boat here... some of you all just have much nicer boats

[spoon059]

Originally Posted by emjayuu

So you get in 10 miles more per hour with accepting large risk to you and other drivers on the road. Slowing down isn't really such a huge impact to "spending time at the lake vs getting there" in my opinion.

And you are entitled to YOUR opinion. Am I entitled to mine?

So 67 mph in a 65 or 70 mph zone is a "large risk"? Read the reply I gave right above this. Speed is the measuring stick for foolish arguments. There are a lot of variables to a safe driver. Doing 70 mph and tailgating in a 40,000 lbs GVWR vehicle is a large risk. Doing 70 on a straight stretch of highway at high noon in the desert with no traffic around in a properly maintained vehicle isn't a risk. What is the difference between these two scenarios?

I'll give you a hint... its not the speed.