Concern with the stock tire speed rating?

[rbryan4]

Originally Posted by Viajante

Speed and load capacity are related: Load capacity decreases as speed increases. The 65 mph speed rating has become standard and it allows a direct comparison of load capacities between different tires. The basic rule is decrease the load capacity by 10% if you drive 10 mph over the speed rating for more than passing. And be sure to have the tires inflated to max pressure. The flip side is that you can seriously exceed load capacity if you only drive 25 mph.

All of that is true, but it doesn't address the OPs concern about the speed rating of the tires Escape uses. I would find it surprising if it's confirmed that they are using Marathons with only a J speed rating, vs the Carlisles with an M speed rating. In this case, the Carlisles are clearly superior. If it has to be Goodyear, then the Endurance with an N speed rating seems to me a much better choice. Having said that, the Marathons I have seen on RV trailers usually have an L speed rating (75 mph), not a J speed rating (62 mph). Hopefully the info the OP had was in error.

[thoer]

Originally Posted by rbryan4

All of that is true, but it doesn't address the OPs concern about the speed rating of the tires Escape uses. I would find it surprising if it's confirmed that they are using Marathons with only a J speed rating, vs the Carlisles with an M speed rating. In this case, the Carlisles are clearly superior.

And Marathons are no longer offered by Goodyear as Dave posted above. There may well be some still for sale until inventory is depleted, but they have been replaced by the Endurance. The only tire I have seen at rallies on new Escapes is the new Carlisle Radial HD, with a speed rating stamped onto the tire of 81mph.

[Viajante]

Originally Posted by jkordzi

Today we had our first call with ETI to go over our build sheet. We are scheduled to pick up our 5.0TA in April. I was told that the tires that come with the 5.0TA are Goodyear Marathon ST205/75R15, which carries a J speed rating (62 MPH). That seems like a very low speed rating to me. I don't plan on towing at 75 mph, but a little extra headroom would be nice. Any idea why ETI doesn't use higher speed tires? Anyone have any issues with these tires? Thanks.

Jkordzi
You will have a little extra headroom if you aren't at the max load and your tires are fully inflated. 62 mph isn't the max speed you are allowed to go, but is used to calculate the max load if you go that speed. you have to know the loaded weight of the trailer to determine how much extra headroom you have. I hope this addresses part of your question.

[rbryan4]

Originally Posted by Viajante

J62 mph isn't the max speed you are allowed to go, but is used to calculate the max load if you go that speed.

Not to be difficult, but I disagree. Virtually every manufacturer and reseller I can find says, in one form or another, that the speed rating is the maximum speed a tire can be driven safely (when properly inflated) based on lab testing - or - the maximum speed a tire can be driven before it doesn't handle as designed.

You can exceed the speed rating of a tire of course, but the manufacturers specifically state that doing so is unsafe - regardless of the load index. While it is true that load is affected by speed, that doesn't provide you any wiggle room to exceed the speed rating of a tire.

[Jim Bennett]

Too confuse things even further, the Marathons I had on my 19 were rated for 65 mph, but if you could increase the pressure by 10 lbs over the minimum recommended pressure for the actual weight, the speed rating could be increased to 75. My tire shop guy just said to always keep your tire pressure at max, and your speed under 120 kph (75 mph).

https://docs.google.com/viewer?url=h...plications.pdf

[rbryan4]

Originally Posted by Jim Bennett

Too confuse things even further, the Marathons I had on my 19 were rated for 65 mph, but if you could increase the pressure by 10 lbs over the minimum recommended pressure for the actual weight, the speed rating could be increased to 75. My tire shop guy just said to always keep your tire pressure at max, and your speed under 120 kph (75 mph).

https://docs.google.com/viewer?url=h...plications.pdf

An interesting point and an example that in certain specific situations where the manufacturer provides such data, you can increase the 'effective' speed rating of a tire with higher inflation pressure. I would not use that to say you can do so with any tire.

And, one more curve ball: the service bulletin posted above also says not to exceed the PSI rating for the wheel or the valve. The HiSpec HWT wheels used by Escape have a max PSI rating of 60 lbs.

[gbaglo]

Originally Posted by Jim Bennett

Too confuse things even further, the Marathons I had on my 19 were rated for 65 mph,

I think that's "rated AT", not "rated FOR".
Small words, big difference.
Back to my hole.

[Ron in BC]

Originally Posted by Eggscape

Interesting...the hwy 40 mins east of the Escape factory is 120 kilometres per hour...or approximately 75 miles per hour.

When I'm not travelling I tow my trailer on that stretch of highway on a weekly basis. I'd rather move with traffic than be a rolling roadblock.



Ron

[Iowa Dave]

Originally Posted by padlin

Dave, do you mean the Endurance as opposed to the Defender? I do see a Defender tire by Michelin.

Yes Bob you are right Endurance. I have the Defenders on the Highlander. Sorry if I confused others. I had a lot on my mind when I wrote that early today. I had to get a haircut, stop at the bank, get some water softener salt at the store, and pick up 2 more tubs of Cool whip. That’s pretty much cranial overload for this old man who will be 70 in a couple weeks. Plus I killed some cells last night drinking cheap Peppermint schapps chased with Mexican beer. I gotta slow down.
Dave

[Iowa Dave]

Originally Posted by Jim Bennett

Too confuse things even further, the Marathons I had on my 19 were rated for 65 mph, but if you could increase the pressure by 10 lbs over the minimum recommended pressure for the actual weight, the speed rating could be increased to 75. My tire shop guy just said to always keep your tire pressure at max, and your speed under 120 kph (75 mph).

https://docs.google.com/viewer?url=h...plications.pdf

That’s how the Marathons on my 19 were run , max inflation, checked every day, and very few days I didn’t flirt with 75 miles an hour on occasion. Closest I could figure they went at least 42,000 miles and still had 4/32 left.
Dave

[Iowa Dave]

Originally Posted by Ron in BC

When I'm not travelling I tow my trailer on that stretch of highway on a weekly basis. I'd rather move with traffic than be a rolling roadblock.



Ron

Ron I’m with you, I drive my speed when I’m out in the open. I’ve taken our Escapes through Chicago about 15 times. When in Chi town do as the Romans do, and hammer down baby. 75 mph not uncommon with wall to wall trucks. Or the coin flips over and you’re stopt dead on the road like a possum. Pay attention
Iowa Dave

[Jim Bennett]

Originally Posted by Ron in BC

When I'm not travelling I tow my trailer on that stretch of highway on a weekly basis. I'd rather move with traffic than be a rolling roadblock.



Ron

I always go with the flow when driving, up to about 10 kph over, to a normal max of 120 kph. I know how much I cuss the slow moving folks on two lane highways, so I'm not going to be one of them. Even on four lane divided going too slow can cause traffic issues.

[Brian B-P]

Originally Posted by Eggscape

Something to go by. I would like at least an M rating...

The root of the following confusion is that this should not be called speed "rating"; the letter is a speed index.

Originally Posted by gbaglo

That chart is confusing or misrepresenting the issue.
It says "Speed Rating D" and claims a max of 40 MPH, but we are talking about "Load Rating D". My Carlisle are Load D and have a speed rating of 81 MPH.
What is the source for that chart?

But the thread topic is not load ratings, or the Load Range (an old-fashioned way to describe the rating of the allowed load); it is the rated operating speed, which is indicated by the speed index. "Load Range D" is completely unrelated to a speed index of "D".

Originally Posted by gbaglo

But, Escape doesn't put Speed Rating D tires on their trailers.
They used Load Rated C when I got my trailer and now I have Load D Carlisles which are speed rated 81 MPH.

Nobody uses tires with a speed index of D - that would only be 40 MPH. baglo, your Carlisles have a Load Range of D and a speed index of M (which corresponds to sustained speeds of 81 MPH).

[jkordzi]

Folks, folks, folks. I'm really sorry I started this. I'm not even sure at this point that I have correct information. I'll check Monday and report back. No need to get wound around the axle.

[cpaharley2008]

Originally Posted by jkordzi

Folks, folks, folks. I'm really sorry I started this. I'm not even sure at this point that I have correct information. I'll check Monday and report back. No need to get wound around the axle.

Welcome to the forum.....

[gbaglo]

Better than watching "Extreme RVs".

[Jim Bennett]

Originally Posted by cpaharley2008

Welcome to the forum.....

And this discussions......

[Steve Clark]

Originally Posted by jkordzi

Folks, folks, folks. I'm really sorry I started this. I'm not even sure at this point that I have correct information. I'll check Monday and report back. No need to get wound around the axle.

I’m not sorry at all! I, and hundreds of others just got the best lesson on load ratings and speed indexes we could ever hope for.

Thank-You All!

[Viajante]

Carlisle website recommends that max speed when towing a trailer should be limited to 60mph. Even if you have Carlisle trailer tires rated at 87mph. So, as you head out of Vegreville on Hwy 16 headed in either direction, keep it under 100kph. See you in the slow lane.

[KarenH]

Originally Posted by Viajante

See you in the slow lane.

No concern whatsoever here if people are cussing at me. That's what the passing lanes are for in my opinion.