Truck Campers- Tires
It’s no coincidence that any truck whose rear axle is listed to allow 6084 lbs maximum has tires that have a maximum load is 3042 lbs each stamped on the sidewall. The logic is simple, if each tire can only carry 3042 lbs each, combine them and that’s 6084, and tires are made of rubber so they are the most flexible and vulnerable part of the suspension system. Nearly all trucks have axles that can carry more than the stock tire ratings, but that information is very hard to find. What you will find however is that many truck campers will weigh more than 3400 lbs loaded and that the total weight on the rear axel will be more than 6084 lbs. Now you’re wondering how those overloaded campers get away with this. Simple, they’ve weighed their rig, determined that it’s overweight, and have done something about it Namely they buy tires and rims that are rated to carry the load they know they have. If in my example, if you have a 4000 lb loaded camper on a truck and the rear axel unloaded weighed 2600 lbs, then you’ve discovered that the rear axel weighs 6600 lbs with the camper on and loaded. What you need are tires and rims that are at least rated to carry that load. The next most common tire rating is 3415 lbs, which would make them capable of supporting 6,830 lbs, which is not much of a margin of error, but it’s better than being overweight. Tires are probably the weakest link in the suspension system. They are susceptible to load, changing air pressure, heat build up and they contact the road where hazards abound. It’s very important to have your truck and camper weighed to make sure your tires are rated to carry the load you are putting on them.
If you decide on changing your stock tire type, there are more things to consider than just the tire's load rating. ¾ and 1 ton trucks usually come with E rated tires, but not all E rated tires have the same load rating. This has to do with much more than tire size. The number of sidewall ply’s, the way the tires are made, tread type and other factors effect what load range can be stamped on the tire. The sizes can be confusing too; I know they are to me. Recently, most trucks have come with 16” diameter rims (Dodges have started coming with 17” rims on some models). But beyond the rim diameter, you must know the width of the rims on your truck. For example, stock Chevrolet 2500HD’s come with a 16”x6.5” rim. Most if not all tires rated for 3415 lbs on a 16” rim requires a 7” wide rim. When I discovered that my camper was too much weight for my stock tires, I immediately went to a larger tire size and ran it on the stock rims for a few thousand miles, but I never relaxed until I upgraded the rims to a wider rim that had the proper load rating stamped on them. For more information on tire sizes and choices on 16” rims use the search feature and type tires into the topic.
I have followed many inquiries for a 16” G rated tire and haven’t seen a true one yet. What is a popular alternative is to upgrade you tires and rims to 19.5” diameter rims. There are many more heavy load tire options in the 19.5” tire size. One big reason is that with the larger rim diameter, the sidewall is smaller and therefore flexes less. But, even though the sidewall is smaller, the overall diameter of the tire will be an inch or two more than your stock tires. This will affect your truck’s speedometer, odometer, ABS possibly, and rear end gear ratio to a small extent. Going to a larger load rated tire on your 16” rims will also probably change the overall diameter too, but not as much as the change in rim size. What you gain with 19.5” rims is a much larger load capacity and if you have an extremely heavy camper, this may be your only safe alternative short of buying a dually truck.
Dually truck owners must also know their tire ratings compared to their actual load. Even these trucks get overloaded and require upgrading stock tire sizes, but they have the added wrinkle of needing to watch for things like being sure the larger tires do not rub together under load.
As you can see, there are a lot of specific questions and considerations when upgrading your tires. Narrow down your choice between staying with your stock rim size, or if your pocketbook allows, upgrading to a larger rim size and then do searches on discussion threads here. There are people with far more tire knowledge than me posting here and they are the ones you need to read. Hopefully the info I’ve provided helps you narrow your focus some.
One new thing to consider when upgrading tires is to think about the valve stem. I know I never have, but an interesting point has been brought up in a topic about The Other Weakest Link.
You seem to be be very knowledgble about tires. My I ask you a question. I have an 04 2500hd diesel that I pull a 5200 lb travel trailer with. I have been looking for a 10 ply, load range E tire with more than a two ply side wall to no avail. I have been to Sams, Discount Tire and Firestone. I can find a D range tire but no Es with 3 ply sidewalls or more. Is a D range safe?
Here's another question, can you recommend some good resources for researching 16" rims that use 5 lugs? My Dodge uses 5 lug 15" rims and in order to get over a Load C tire, I need to go to 16".
Follow me as I full-time the Redneck Way at The Journey of the Redneck Express CBChannel 17Redneck Express '1992Dodge W-250 "Dually" Power Wagon - Club Cab Long Bed 4x4 V8 5.9L gashog w/4.10 Geared axles '1974KIT Kamper 1106 - 11' Slide-in
www.arrowcraft.com I believe is their home site, but their adapters are for going to dual rear wheels. My other concern would be the adapters changing the load carrying on the bearings. We're already working with a 1/2 ton truck, don't want to change the load on the bearings abnormally.
ramblingly brings up a good question. Why would his truck come with the 3415 load capable tires and still be rated for 6084 on the rear axle. I would guess, and it is only a guess, that Ford does put the 3042 tires on some trucks at some times and it is easier to not keep track and/or that the springs may be rated at 6084. Chevy lists the suspension and the axle separately in new brochures. Suspension on a Chevy 2500HD is 6084, and the axle is listed at 6900 lbs.
Nearly everyone putting a camper on a single wheel vehicle has to add air and/or helper springs which augments the stock springs and in theory increases their load capabilities. So even if the springs themselves were only rated truly for 6084 lbs, the additional equipment does help. That help would still be useless if the tires remain rated for only 6084 lbs combined. For ramblingly, tire upgrades were not necessary, very convenient. Wish mine had come that way, I still had good life on the old tires which are sitting in a shed right now.