LT tires

[sambam]

I'm beginning to search for new tires to replace my Marathons and have noticed a good number of you use LT tires as opposed to ST's.
The question I have is the load range of these tires. I have looked on several manufacturers web-sites, Goodyear, BF Goodrich, Maxxis, Firestone, to name a few. None of these have LT tires with a load rating high enough for my camper. In fact I didn't even see any with load ratings as high as these Marathons. Maybe I'm missing something, but my Montana can't be that much heavier than any of yours, so what gives? I am also interested in the G614, but being a weekend warrior, I'm thinking I don't need all that, at least 'til I retire and begin to fulltime. My axles are 7000 lb. so would like to have at least a 3500 lb. load range. I am trying to work a deal out with GY for the G614's in exchange for my tires. If they work with me, I'll most certainly go that route, but if not, I need a back-up plan. So, where is my thinking going wrong about these LT's?

[fauch]

Speed rating vs load rating.
We use up the load rating of an ST tire with highway speeds

An LT tire OTOH at say a 106 mph speed rating, has a greater load capacity at 65mph than the load rating printed on the tire, which is commensurate to it's speed rating.

maybe this will help:
http://www.bridgestonetrucktires.com...4/v3i4Tech.asp

[Art-n-Marge]

It's about what's called reserve capacity. I believe you wanna get in touch with DQDick who oftens posts information describing this very well when this subject comes up. Or get in touch with LonnieB, MOC's tire expert (manages a Tire Rack in New Mexico). I don't have the answers off the top of my head, but there's some folks to contact.

As for STs, Maxxis or Sailun are possibilities.

[steelpony5555]

Your thinking is not wrong. Most LT tires are are rated for 3042 lbs and ST tires are at around 3400 lbs I think. But LT tires being "passenger" vehicle tires are held to a higher testing standard then ST tires. The ST tires are rated at the max they can possibly care but the LT tires are rated with a cushion built in. Now I did read this somewhere I just forget where. But if you have 7000 lb axles I would go with the G614 tires. If your trailer had Marathons on it the LT tires in my opinion and my opinion only would still be a step up. But to be in spec I would put tires on that have the numbers to match your running gear......

[DQDick]

Give me an email at dqdick10432@yahoo.com and I'll send you an article that's been around the internet for years that will make the issue clearer for you.

[fauch]

That article might be valuable for all of us.
The reason there are so many trailer tire failures is related to speed:load rating. If we payed attention to and heeded the labeling on tires this never ending discussion would get simpler. Please see article in link in my last post above. The chart illustrates the effect of speed on capacity. E rated LTs do not reach their capacity until 106mph. G rated Sts capacity are maxed at 75 mph. There is a near linear correlation between capacity decrease per speed increase. THIS IS the reason that there are so many trailer tire failures. So to respond to Dave's OP question again, please see the chart in my post above and it will help you to understand why a 3042 lb. rated LT tire (@ 106 mph) may be a better choice than a 3500 lb. rated ST tire (@75 mph)

[Phil P]

Hi

I am not sure what you all are talking about.

My commercial truck tire dealer has “G” rated 3750 lb LT tires.

Phil P

[Chip]

Shouldn't the first question be "what does the rig weigh fully loaded?"

[WeBeFulltime]

quote:Originally posted by Chip

Shouldn't the first question be "what does the rig weigh fully loaded?"

In my opinion the weight that really matters is the total weight of both axles while hooked to truck and ready to travel. That is the weight that the tires are supporting.

[1retired06]

You were looking for an option other than G614s. For the past ten years I have run Firestone TransForce LT tires on all three of my Montana's without a single blowout or issue.

[sambam]

quote:Originally posted by 1retired06

You were looking for an option other than G614s. For the past ten years I have run Firestone TransForce LT tires on all three of my Montana's without a single blowout or issue.

Those tires are in the discussion should I go with LT's. I have them on my truck and am very happy with them.

[DQDick]

In my opinion the weight that really matters is the total weight of both axles while hooked to truck and ready to travel. That is the weight that the tires are supporting.
[/quote]

I believe in taking it a step further. Since we have large pantries and refrigerators, in our case file cabinets and a whole lot of tools, and we have large basements to carry all kinds of stuff, I'm concerned with the weight on each individual wheel. You can get that information from any of the Escapee parks that do weighing and sometimes from the folks who travel to rallies and events.

[mhs4771]

Just be advised, if you go to a reputable Tire Shop there is a strong possibility they will not install tires with a lesser capacity than what's on the sticker on the front road side of the Monty. Now there are many shops will not look at the sticker and will install what ever you want.

[Art-n-Marge]

The weight rating to use for getting the correct tire is the wheel rating on the ends of the axle. I have 6,000 lb axles, then each wheel must be rated at a minimum of 3,000 lbs. If you only use the actual weight at the scale and each tire only weighs 2,500 lbs, then you can never carry another thing because that object could put your wheels at a new weight. Instead you want to use the maximum rating of the wheel and ensure you have some margin. I do currently have Marathons rated over 3,400 lbs so I not only satisfy the axle rating, I have some margin. My tires are approaching 6 years old and I will be replacing them prior to our next outing (probably in summer).

DQDick does have a great recommendation, that you must also know your individual wheel weights (only a scale can measure this), to ensure your rig wheel's are each below the rating. For example on my rig, all weights are about 2,700 lbs except the passenger rear at 2,400. It's been a while since I've been to the scales and hope to do this prior to getting my next set of tires, just to ensure things are still okay. Knowing ratings is required, but knowing your actual weights are within your ratings is even more important.

[steelpony5555]

What mhs4771 says is important because you may have a tire shop in your town that is ok with putting lower rated tires on a 7k axle. But if you are on the road and have a problem, you may have trouble finding a tire shop that will help if they see 3k lb tires on a 7k lb axle...... May not happen but have seen stranger.....

[sambam]

Thanks you all for your responses. I have a clearer understanding of load ranges and reserve capacities now. Dick sent me some info and I checked out the link from fauch and it makes some sense. But, how do you know what your reserve is at a given mph? OK, so you buy an LT tire with a speed rating @ 106 and a load range of 3042. How does that compute to 60-65 mph, which is where I'll be with the trailer on the back? Is there a formula? Blind faith? It seems a little ambiguous to me. I'm not trying to discredit the science, just trying to understand it. You all seem to know a bit about this so I'll keep digging 'til I get it, too.

[rohrmann]

There's no worry if you just go with G614's. Makes the weight rating and you can go 65 mph all day long, and you should be able to get service from most tire places anywhere across the country. Just keep them at 110 psi and you're good. Weekend warrior or full time, the damage from a failed tire costs the same.

[Bigsky3625RE]

We upgraded to 17.5" wheels and GY G114 tires. Lots of safety margin. One less thing to worry about.

No need to wait to be a fulltimer to be safe.

In my mind, these tires are carrying more than a trailer. They have the potential to cause harm if they fail. To our family and others.

Travel safe.

Ken and Jackie

[mach111]

OK, no body has mentioned rims here. OP has '10 Monty. He needs to ensure his rims can handle 110 PSI. Probably can since unit is 2010. OP needs to inspect back side of rim for his specs. My 09 has 80-85 Psi rims. Being held to only 85 PSI limits the weight rating. According to my individual loaded wheel weights Michelins XPS and my 85psi rims can handle the weights. Yes I do have 6k axles.

One needs to start with the weights of each wheel loaded and make the decisions. Love to follow these tire threads for I learn more info each time.

[JandC]

quote:Originally posted by rohrmann

There's no worry if you just go with G614's. Makes the weight rating and you can go 65 mph all day long, and you should be able to get service from most tire places anywhere across the country. Just keep them at 110 psi and you're good. Weekend warrior or full time, the damage from a failed tire costs the same.

That says it all. Our first Montana was used and already had the G614 tires, but the new one did not leave the dealership without having new G614's installed to replace the junk factory supplied tires. I didn't want to add that cost when purchasing the new unit but didn't feel I had any choice. IMHO the two most important things that can't fail when towing these weights are brakes and tires. Why not go with a proven tire that will probably never fail?