How to spec max tow and HD payload?
07-19-2013, 01:18 PM
#11
Senior Member
07-19-2013, 05:26 PM
#12
Says the guy with the ideally smooth roads lol. It gets harsh when you have to go over potholes, dips, and road deflections day in and day out.
07-19-2013, 07:13 PM
#13
Senior Member
I have the HD payload and the ride with the LT's is actually smoother than my nissan maxima with low profile tires. It's my daily driver and its great. My last truck only had P tires on it and its wasn't any smoother in my opinion. A bumpy harsh road is bad regardless of the tires and a nice smooth road is no different. Get the LT's you will be happier in the long run if you use a truck as a truck.
07-21-2013, 10:17 PM
#14
Grumpy Old Man
You need to find a load/inflation table for your exact construction and size of tire.
The HD Payload Package comes with LT245/75R17E tires. Brand doesn't matter as long as they are LT245/75R17E. So here is the load/inflation table reprinted by Toyo from the original Tire&Rim Assn tables:
LT245/75R17E Single:
PSI. Max Weight
35 . 1770
40 . 1945
45 . 2110
50 . 2270
55 . 2430
60 . 2595
65 . 2755
70 . 2900
75 . 3050
80 . 3195
If you look on the tire, the only load inflation number you will see is 3195 pounds @ 80 PSI. But if you do enough digging, you will find the above table.
It says that at 35 PSI, that tire has a weight capacity of 1,770 pounds when mounted on an axle that has single tires (not duals).
You want to have the right amount of air pressure in the tire to support the load you will be hauling on that axle. The minimum is the amount shown in the above table for the weight on the tire. Over-inflation by 5 to 10 PSI is okay, but under-inflation is never okay. So on my F-150 when towing I have 3840 pounds on the rear axle, or 1920 pounds on each tire. So per that table I need at least 40 PSI in those LT245/75R17E tires when towing. If I prefer a little fudge factor, I could run 45 PSI and have a lot more tire weight capacity than I need. So those tires that can hold as much as 80 PSI would be overkill for my F-150.
But if I had those tires on an F-150 with the HD payload pkg, and my wet and loaded rear axle weight was 4,250 or 2,125 per tire, how much PSI would I need? 45 is not enough, but 50 is plenty. So with 4,250 pounds on the rear axle, I should run 50 PSI in the rear tires. That's a lot less than the 60 PSI on the door or 80 PSI max on the tire sidewall, but the guru engineers at the Tire&Rim Assn say that's all I need. More than 50 PSI and I'll have a rougher ride, and the center of the tread will wear faster. But less than 50 PSI won't give me enough weight capacity to haul my load, so the tire will overheat and probably blow out.
The lawyers have the tire companies scared to death of lawsuits, so most won't provide needed load/inflation info easily. They believe the average Joe is to stupid to understand and apply a load/inflation table. So they tell you to follow the vehicle manufacturer's guidelines (then you cannot sue them, you have to sue Ford if you have tire problems). The info is available, but you have to dig it out.
The source is the Tire and Rim Assn's annual report to members. But membership is expensive so you and I aren't members. Michelin truck website has some of the data for bigger trucks and motorhomes, but not for light trucks. BFGoodrich is part of Michelin, so you probably won't find load/inflation tables or BFGoodrich tires either. You probably can't find it for P-series or LT tires on Bridgestone or Goodyear websites . Toyo still makes it available, so that is where I found the above table. But you better hurry before Toyo realizes that they are a lawsuit target by making those tables available to Average Joe.
http://toyotires.com/tires-101/load-...flation-tables
The HD Payload Package comes with LT245/75R17E tires. Brand doesn't matter as long as they are LT245/75R17E. So here is the load/inflation table reprinted by Toyo from the original Tire&Rim Assn tables:
LT245/75R17E Single:
PSI. Max Weight
35 . 1770
40 . 1945
45 . 2110
50 . 2270
55 . 2430
60 . 2595
65 . 2755
70 . 2900
75 . 3050
80 . 3195
If you look on the tire, the only load inflation number you will see is 3195 pounds @ 80 PSI. But if you do enough digging, you will find the above table.
It says that at 35 PSI, that tire has a weight capacity of 1,770 pounds when mounted on an axle that has single tires (not duals).
You want to have the right amount of air pressure in the tire to support the load you will be hauling on that axle. The minimum is the amount shown in the above table for the weight on the tire. Over-inflation by 5 to 10 PSI is okay, but under-inflation is never okay. So on my F-150 when towing I have 3840 pounds on the rear axle, or 1920 pounds on each tire. So per that table I need at least 40 PSI in those LT245/75R17E tires when towing. If I prefer a little fudge factor, I could run 45 PSI and have a lot more tire weight capacity than I need. So those tires that can hold as much as 80 PSI would be overkill for my F-150.
But if I had those tires on an F-150 with the HD payload pkg, and my wet and loaded rear axle weight was 4,250 or 2,125 per tire, how much PSI would I need? 45 is not enough, but 50 is plenty. So with 4,250 pounds on the rear axle, I should run 50 PSI in the rear tires. That's a lot less than the 60 PSI on the door or 80 PSI max on the tire sidewall, but the guru engineers at the Tire&Rim Assn say that's all I need. More than 50 PSI and I'll have a rougher ride, and the center of the tread will wear faster. But less than 50 PSI won't give me enough weight capacity to haul my load, so the tire will overheat and probably blow out.
The lawyers have the tire companies scared to death of lawsuits, so most won't provide needed load/inflation info easily. They believe the average Joe is to stupid to understand and apply a load/inflation table. So they tell you to follow the vehicle manufacturer's guidelines (then you cannot sue them, you have to sue Ford if you have tire problems). The info is available, but you have to dig it out.
The source is the Tire and Rim Assn's annual report to members. But membership is expensive so you and I aren't members. Michelin truck website has some of the data for bigger trucks and motorhomes, but not for light trucks. BFGoodrich is part of Michelin, so you probably won't find load/inflation tables or BFGoodrich tires either. You probably can't find it for P-series or LT tires on Bridgestone or Goodyear websites . Toyo still makes it available, so that is where I found the above table. But you better hurry before Toyo realizes that they are a lawsuit target by making those tables available to Average Joe.
http://toyotires.com/tires-101/load-...flation-tables
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SkiSmuggs (07-22-2013)
07-21-2013, 10:29 PM
#15
Senior Member
You need to find a load/inflation table for your exact construction and size of tire.
The HD Payload Package comes with LT245/75R17E tires. Brand doesn't matter as long as they are LT245/75R17E. So here is the load/inflation table reprinted by Toyo from the original Tire&Rim Assn tables:
LT245/75R17E Single:
PSI. Max Weight
35 . 1770
40 . 1945
45 . 2110
50 . 2270
55 . 2430
60 . 2595
65 . 2755
70 . 2900
75 . 3050
80 . 3195
If you look on the tire, the only load inflation number you will see is 3195 pounds @ 80 PSI. But if you do enough digging, you will find the above table.
It says that at 35 PSI, that tire has a weight capacity of 1,770 pounds when mounted on an axle that has single tires (not duals).
You want to have the right amount of air pressure in the tire to support the load you will be hauling on that axle. The minimum is the amount shown in the above table for the weight on the tire. Over-inflation by 5 to 10 PSI is okay, but under-inflation is never okay. So on my F-150 when towing I have 3840 pounds on the rear axle, or 1920 pounds on each tire. So per that table I need at least 40 PSI in those LT245/75R17E tires when towing. If I prefer a little fudge factor, I could run 45 PSI and have a lot more tire weight capacity than I need. So those tires that can hold as much as 80 PSI would be overkill for my F-150.
But if I had those tires on an F-150 with the HD payload pkg, and my wet and loaded rear axle weight was 4,250 or 2,125 per tire, how much PSI would I need? 45 is not enough, but 50 is plenty. So with 4,250 pounds on the rear axle, I should run 50 PSI in the rear tires. That's a lot less than the 60 PSI on the door or 80 PSI max on the tire sidewall, but the guru engineers at the Tire&Rim Assn say that's all I need. More than 50 PSI and I'll have a rougher ride, and the center of the tread will wear faster. But less than 50 PSI won't give me enough weight capacity to haul my load, so the tire will overheat and probably blow out.
The lawyers have the tire companies scared to death of lawsuits, so most won't provide needed load/inflation info easily. They believe the average Joe is to stupid to understand and apply a load/inflation table. So they tell you to follow the vehicle manufacturer's guidelines (then you cannot sue them, you have to sue Ford if you have tire problems). The info is available, but you have to dig it out.
The source is the Tire and Rim Assn's annual report to members. But membership is expensive so you and I aren't members. Michelin truck website has some of the data for bigger trucks and motorhomes, but not for light trucks. BFGoodrich is part of Michelin, so you probably won't find load/inflation tables or BFGoodrich tires either. You probably can't find it for P-series or LT tires on Bridgestone or Goodyear websites . Toyo still makes it available, so that is where I found the above table. But you better hurry before Toyo realizes that they are a lawsuit target by making those tables available to Average Joe.
http://toyotires.com/tires-101/load-...flation-tables
The HD Payload Package comes with LT245/75R17E tires. Brand doesn't matter as long as they are LT245/75R17E. So here is the load/inflation table reprinted by Toyo from the original Tire&Rim Assn tables:
LT245/75R17E Single:
PSI. Max Weight
35 . 1770
40 . 1945
45 . 2110
50 . 2270
55 . 2430
60 . 2595
65 . 2755
70 . 2900
75 . 3050
80 . 3195
If you look on the tire, the only load inflation number you will see is 3195 pounds @ 80 PSI. But if you do enough digging, you will find the above table.
It says that at 35 PSI, that tire has a weight capacity of 1,770 pounds when mounted on an axle that has single tires (not duals).
You want to have the right amount of air pressure in the tire to support the load you will be hauling on that axle. The minimum is the amount shown in the above table for the weight on the tire. Over-inflation by 5 to 10 PSI is okay, but under-inflation is never okay. So on my F-150 when towing I have 3840 pounds on the rear axle, or 1920 pounds on each tire. So per that table I need at least 40 PSI in those LT245/75R17E tires when towing. If I prefer a little fudge factor, I could run 45 PSI and have a lot more tire weight capacity than I need. So those tires that can hold as much as 80 PSI would be overkill for my F-150.
But if I had those tires on an F-150 with the HD payload pkg, and my wet and loaded rear axle weight was 4,250 or 2,125 per tire, how much PSI would I need? 45 is not enough, but 50 is plenty. So with 4,250 pounds on the rear axle, I should run 50 PSI in the rear tires. That's a lot less than the 60 PSI on the door or 80 PSI max on the tire sidewall, but the guru engineers at the Tire&Rim Assn say that's all I need. More than 50 PSI and I'll have a rougher ride, and the center of the tread will wear faster. But less than 50 PSI won't give me enough weight capacity to haul my load, so the tire will overheat and probably blow out.
The lawyers have the tire companies scared to death of lawsuits, so most won't provide needed load/inflation info easily. They believe the average Joe is to stupid to understand and apply a load/inflation table. So they tell you to follow the vehicle manufacturer's guidelines (then you cannot sue them, you have to sue Ford if you have tire problems). The info is available, but you have to dig it out.
The source is the Tire and Rim Assn's annual report to members. But membership is expensive so you and I aren't members. Michelin truck website has some of the data for bigger trucks and motorhomes, but not for light trucks. BFGoodrich is part of Michelin, so you probably won't find load/inflation tables or BFGoodrich tires either. You probably can't find it for P-series or LT tires on Bridgestone or Goodyear websites . Toyo still makes it available, so that is where I found the above table. But you better hurry before Toyo realizes that they are a lawsuit target by making those tables available to Average Joe.
http://toyotires.com/tires-101/load-...flation-tables
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