Tire load range and index

[osprey92]

I am currently running my second set of tires but due to a belt separation issue I am looking for replacements. One thing I haven't considered is load range or index as an influence as part of recommendations, but I am now. When a tire is E rated/121, it's fully inflated load capacity is 3297LBS. Multiply that by four tires (4 x 3,297 = 13,188 pounds) to get the max load carrying capacity. Do I need to subtract the Gross Vehicle Weight Rating Cap of the truck (2017 Ram 1500 Tradesman 4x4 Crew) @6800lbs from the tires' max load carrying capacity to understand the remaining weight capacity of the tires?

TIA

 

[audiophile]

Did your truck come with LTs?

 

[crazykid1994]

What truck? 1500? 2500? It doesn’t matter what the tires are. Your truck is specd to a certain payload. That’s what you go off of. Your axles and suspension are your limit. Even the stock tires on a 1500 are higher load than the truck is rated for. My 2017 1500 has a payload around 1400lbs if I remember correctly. 7000lbs max gvwr. That’s what matters. The stock sr-a tires are around 2000lbs each for a total of 8000lbs. You would never max those tires without being over payload. You could beef up all the suspension to match the axles which are 7800lbs together but that’s still less than the stock tires were. Either you got a bad tire or you are doing things that truck is not meant to be doing. Only time I’ve ever had a tire separate were cheap ass tires on my company work van.

 

[osprey92]

Did your truck come with LTs?

No idea. The stock tires from the factory that wore out after 27K miles. The Cooper ATs have had a growing belt issue on one for 33k miles. I hate to change then as they have about half of tread left but the ride is so annoying.

 

[osprey92]

What truck? 1500? 2500? It doesn’t matter what the tires are. Your truck is specd to a certain payload. That’s what you go off of. Your axles and suspension are your limit. Even the stock tires on a 1500 are higher load than the truck is rated for. My 2017 1500 has a payload around 1400lbs if I remember correctly. 7000lbs max gvwr. That’s what matters. The stock sr-a tires are around 2000lbs each for a total of 8000lbs. You would never max those tires without being over payload. You could beef up all the suspension to match the axles which are 7800lbs together but that’s still less than the stock tires were. Either you got a bad tire or you are doing things that truck is not meant to be doing. Only time I’ve ever had a tire separate were cheap ass tires on my company work van.

Thanks. I was simply asking about the remaining weight capacity of the tires. From your reply, if I maxed the gvwr I would only be at ~50% of the tires supported load weight capability.

 

[crazykid1994]

Thanks. I was simply asking about the remaining weight capacity of the tires. From your reply, if I maxed the gvwr I would only be at ~50% of the tires supported load weight capability.

Sounds about right. I have 305/70r18 Mickey Thompson atz p3 on my truck and those are way over my trucks gvwr. I think they were close to double like yours is.

 

[danielmid]

Sounds about right. I have 305/70r18 Mickey Thompson atz p3 on my truck and those are way over my trucks gvwr. I think they were close to double like yours is.

Yup about the same here, 35x12.5r17 E2 rated on my 1500, way over tired for payload, tires don't increase payload

 

[Jeepwalker]

Just curious how you determined it's a belt issue?

Well lets see ...a new set of LT's are probably going to run, let's say, ~ $240ea ..figuring you get a decent deal. They could be higher at $275ea if you go with a higher priced and better LT too. Plus $80 for balance and disposal. But going with the $240/set, it comes out to $1040.00 for a set of tires (not incl press sensors or tax).

So...when you say half ...is it really half? Or more like 40% or 55%? If it's 40% and you live in a snowy area, probably better to just replace them. OR ....if they're on the high-side of half, if it were my truck, what I might be inclined to do is take the vehicle in and get the tires Road Force balanced on a Hunter Road Force balancing machine. That'll tell you exactly which tire/s have uneveness, and how bad. It'll give you a score too ..a number you can go off of. Then you can make educated decisions.

If it's just one tire, I would probably look for a used same-tire off Facebook ...probably buy a tire for $75 if it's half tread. You see tires come up all the time. Then for $100 (figuring balancing) you could get another couple years out of them. Or, you could buy a brand new same Cooper tire matching what you have, put it on the rear star wheel (usually the rear Rt axle) where it'll wear faster to match the other tire tread height sooner. Unless your truck has a limited slip, in which case I probably wouldn't do that). But if it's an open rear diff, put it on the rear right and don't rotate it for a couple rotations ...and it'll wear down faster back there till it matches the other 3. Or pretty close to it. And you'll still get the few extra years of wear for $100. So if you're the thrifty type, that's one course of action.

If you have two tires which have belt or wear issues, then I'd be looking at a new set of tires ...and also what, if anything caused the issues: worn shocks, bad ball and steering joints or too much pressure. People tend to want to blame the tires, but often it's a symptom of other things. Sometimes a shock may not be leaking and can work ok throughout it's full travel, but be 'loose' in the center portion of its travel ...and cause wheel hop, which can make tires wear unevenly and even get bouncy. They say, once a tire has created a certain wear pattern (like a bounce) you can't really correct it (I'm going from what I read in magazines).

I just put new LT meats on my Hummer and discovered in the inspection process, one of my front shocks, the main rod had broken below the shield (wasn't visible). I had planned to replace the shocks anyway, I knew I had one leaking. But that's kind of thing to look for


Just ideas to ponder...

 

[CheechDogg.0n37s]

Just curious how you determined it's a belt issue?

Well lets see ...a new set of LT's are probably going to run you, let's say, ~ $240ea ..figuring you get a decent deal (they could be 275ea if you go with a higher priced tire). Plus $80 for balance and disposal. That's $1040.00 for a set of tires (not incl press sensors or tax).

So...when you say half ...is it really half? Or more like 40%? If it's 40% and you live in a snowy area, probably better to just replace them. OR ....if they're on the high-side of half, if it were my truck, what I might be inclined to do is take the vehicle in and get the tires Road Force balanced on a Hunter Road Force balancing machine. That'll tell you exactly which tire had the tread problem, and how bad. Then you can make educated decisions.

If it's just one tire, then I would probably buy the same tire off Facebook ...probably buy a tire for $75 if it's half tread. You see tires come up all the time. Or, you could buy a brand new same Cooper tire and put it on the rear star wheel (usually the rear Rt axle). Unless your truck has a limited slip, in which case I probably wouldn't do that. But if it's an open rear diff, put it on the rear right and don't rotate it for a couple rotations ...and it'll wear down faster back there till it matches the other 3. Or pretty close to it.

If you have two tires which have belt or wear issues, then I'd be looking at a new set of tires ...and also if you have worn shocks. That can cause bouncing and lead to cupping and uneven wear (as well as bad ball and steering joints and too much pressure).

Just ideas to ponder...

The road force balance is not going to tell you what tire has the issue because just about every tire will have a an area where the force is detected ...

I know what you mean though, but that's not how it works especially on tires that already have 30k+ miles ...

That tire after being put through a road force balance test is probably going to require a ridiculous amount of weight to balance it, waste of money to test a tire that he already knows has an issue...

I would just get new tires if the ride is rough ... and get good quality tires not cheap ones ... I know its hard sometimes for people, but tires is one area for my vehicles that I don't cheap on ... it will cost more down the road buying cheap tires as they can cause other issues like suspension parts getting tore up ... nah...nopefawkdhat!!! ...

 

[Jeepwalker]

I agree it's a judgement call. I'm operating on the remark the OP made that he'd 'like' to run them longer if he could. If money isn't an issue, yeah, get new tires. If it is, then, the quiestion is, is it worth to buy one new tire $240+$80 (balance)=$320 and run the set another 3 years? ($320 vs $1040). Maybe, maybe not. The OP knows his money situation better than I do. It might be if the OP goes to a local tire shop, they'd work with him on tire inspections and balancing. They might have a decent 50% used (same size) tire on the rack they could sell, and the OP might get out the door for $150. Then I'd say, if that's the case, it probably is worth it to replace a single bad tire and run the rest a couple more years. Unless he just doesn't like the ride or wants new tires. But there's no guarantee the next set will ride any smoother. Unless ya go with Michelins or Goodyears.

It probably wouldn't hurt for the OP to check around with a few local tire shops and see what they say/think. Do they have a similar (used) tire to the Cooper? Otherwise, the OP won't go wrong with new tires .....except he might be forfeiting $500 worth of tire wear "if" there are 3 usable tires.

 

[CheechDogg.0n37s]

I agree it's a judgement call. I'm operating on the remark the OP made that he'd 'like' to run them longer if he could. If money isn't an issue, yeah, get new tires. If it is, then, the quiestion is, is it worth to buy one new tire $240+$80 (balance)=$320 and run the set another 3 years? ($320 vs $1040). Maybe, maybe not. The OP knows his money situation better than I do. It might be if the OP goes to a local tire shop, they'd work with him on tire inspections and balancing. They might have a decent 50% used (same size) tire on the rack they could sell, and the OP might get out the door for $150. Then I'd say, if that's the case, it probably is worth it to replace a single bad tire and run the rest a couple more years. Unless he just doesn't like the ride or wants new tires. But there's no guarantee the next set will ride any smoother. Unless ya go with Michelins or Goodyears.

It probably wouldn't hurt for the OP to check around with a few local tire shops and see what they say/think. Do they have a similar (used) tire to the Cooper? Otherwise, the OP won't go wrong with new tires .....except he might be forfeiting $500 worth of tire wear "if" there are 3 usable tires.

I agree .... it's just very frustrating that there is so much misinformation about what the Road Force Balance machines and overall method is actually meant for ....

If my tire is that bad that it needs to be road force balanced after 30k miles and they are high profile tires like 35"s or 37"s, I am not going to even "fawkaroundNfindout" lol

Road Force balance is meant for low profile tires and tires from factory, most vehicle manufacturers now use road force machines at the factory to make sure that they send every vehicle to the lots with the best possible tires at a cheap price lol ...

I have mentioned before in other posts, we were not allowed to use the road force balance machine unless they were new tires or high end vehicles that needed a rebalance and tire rotation ... a proper road force balance costs anywhere from $50 - $100 per tire if you go to a shop that actually performs the correct Road Force balance procedures ...

Sometimes you have to dismount the tires, switch them to another wheel, spin the tire on the wheel, the machine will tell you exactly what to do but most don't do every step, just spin the tire and put the weight it's asking without even trying to drop the weight it's asking by spinning the tire lol ..

Road Force balancing should only be used on new tires from the start, it's pointless running a tire through the road force balancer when you already have a few thousand miles and possible damage or prior issues with those tires ...

We sent back at least 30 sets of tires every week because they didn't meet our standards, we offered the Road Force balance on every new set for an additional fee which was usually $200 extra and most people declined it lol ...

 

[Jeepwalker]

...a proper road force balance costs anywhere from $50 - $100 per tire if you go to a shop that actually performs the correct Road Force balance procedures.

I guess Im lucky to have a helpful buddy who helps me out on balance jobs..

Some shops use as a diagnostic for tires which are problematic. $100 a tire charge wouldn't make it worth doing, I agree. Some shops, like GM garages, the smaller ones might only have one balancer ...and it would be a Road Force balancer as they are required to have at least one.

 

[osprey92]

Folks - thanks for all the feedback. Yes, it is cheaper to thrown on a half-life Cooper tire @ $75 + $25 balance and install. Not sure I like riding on a set that has a belt issue. Coupled with the fact that they have horrible wet traction from stop to initial acceleration, I'm ready to replace the set and re-sale 3 that are salvageable. Not sure why, but tires where I live and purchase @ Walmart seem are 50-60% cheaper then what you are quoting. Throw in a Black Friday special and get another 10-15% off.
But my real questions was related to understanding load the tires can support. No need to get a Class E/121 tire when a 115 with enhanced sidewall reinforcement will work for $30 less per tire and still give you 30% room over GVWR.

 

[CheechDogg.0n37s]

I guess Im lucky to have a helpful buddy who helps me out on balance jobs..

Some shops use as a diagnostic for tires which are problematic. $100 a tire charge wouldn't make it worth doing, I agree. Some shops, like GM garages, the smaller ones might only have one balancer ...and it would be a Road Force balancer as they are required to have at least one.

Yeep.. I was lucky to have worked for and with a really good bunch of old times when I started working for Big O Tires .... every chance they had to show me something they called me over and said pay attention, do this, do that ... my first week working at Big O Tires and they had me helping them with the alignments lol ... setting up the sensors, locking the wheel, breaking lose the nuts then finally actually getting to do the alignments ..

With the tires and wheels they were even more strict, when I tell you these old timers loved their job and the compliments they got from customers it was nothing short of amazing ... Then a new management team and front desk staff was hired and they were all about numbers, quantity and the quality of work just dipped ... they would celebrate when they got a single soccer Mom bite on the bs lies about their tires needing to be replaced, their engine needs a repair, this and that ...

If you haven't already noticed JeepWalker I am really high on "Integrity" and hate dubious and unscrupulous individuals and because of that experience I got and had at Big O Tires with the ****** staff and management, I just couldn't be a part of something like that ... Moms and old people getting screwed over for hundreds and sometimes thousands of dollars ...

Just not cool man ...

But you are lucky if you have a good buddy with a shop than can hook you up man, those kind of friends are hard to come by and more so keep around .... appreciate it and show him you do ..

 

[62Blazer]

I am currently running my second set of tires but due to a belt separation issue I am looking for replacements. One thing I haven't considered is load range or index as an influence as part of recommendations, but I am now. When a tire is E rated/121, it's fully inflated load capacity is 3297LBS. Multiply that by four tires (4 x 3,297 = 13,188 pounds) to get the max load carrying capacity. Do I need to subtract the Gross Vehicle Weight Rating Cap of the truck (2017 Ram 1500 Tradesman 4x4 Crew) @6800lbs from the tires' max load carrying capacity to understand the remaining weight capacity of the tires?

TIA

So yes, but that is basically 6 one way and an 1/2 dozen the other. The weight rating of the tire is the total load it can support which includes the weight of the vehicle itself. If you want to know how much payload you could put on the truck and stay within the tire load ratings then theoretically yes, you would subtract the weight of the truck to see what is left. But it's also a moot point because those tires have WAY more weight rating than what the truck does. I would like to see 6,000+ lbs. of load placed in a 1500 series truck so make sure to take pics!