New Tires

Grit dog wrote:
Toyo MTs are 3950lb for the 295-70-17 size. Not sure about other sizes but that's about the closest to 4k if we for a 17" tire.
I have them on my Ram and so far they are a great tire. Not great great life since I got them siped and hauled a 4klb camper but they are solid. Have beat them up pretty bad on rocky roads with the camper and no flats.

I ran the 295s on my '07 Ram 3500 SRW. You're right,the Toyo MTs are hell for stout.

That's a very shortsighted view. I were to remove a leaf spring or put on bling low profile wheels that are only rated for 2500 lbs, you feel that the vehicle is still rated for the sticker.

Conversely, if I increase capacity of the weakest components, why wouldn't capacities increase?

I just hope you realize legal is different than practical...

Bedlam wrote:
The ratings are based on how the vehicle was originally equipped. Are you arguing there is nothing you can do to a vehicle that will increase or decrease its functional rating outside of the sticker?

Until you retest the vehicle IAW the FMVSS testing standards and protocols and are able to affix a different GVWR sticker or are authorized to modify the sticker and affix a new one IAW with again very strict and detailed FMVSS procedures (generally done for some upfitters for chassis type vehicles, etc.) that is correct the sticker remains the governing certification and as an individual there is nothing you can do to legally change it.

Larry

The ratings are based on how the vehicle was originally equipped. Are you arguing there is nothing you can do to a vehicle that will increase or decrease its functional rating outside of the sticker?

BertP wrote:

Miles Away wrote:
Bert:
I understand. Be careful that you don't exceed your vehicle GVWR as that is an established (legal) limit and is not changed by different tires, springs, airbags or just about anything else. To keep it legal, stay with what you have, aired up to 80 psi (if that is the max psi for your tires)and you should not have any issues.

That's what I used to think as well, but if you check the laws, you will not find a single instance in the US or Canada where the manufacturer's GVWR is the legal limit for any vehicle. Most jurisdictions state that you can tow or load up your vehicle with anything you want as long as it is "safe". They neglect to define "safe", though. So, that's why I would like to have 4,000 lb tires. I will hit the limit of my truck long before I hit the limit of my tires thus reducing the likelihood that my vehicle will be labeled as being "unsafe".

It is strictly bureaucratic so there is little or no logic to it. But, it is the law.

There is some logic to my madness, though. We tend to look at our tires and think that as long as each tire's capacity is greater than half the load on the axle, then we are good to go. After all, half of the axle's load is on each tire, right? That's true if you are driving on level roads. I am considering using my TV in a more commercial setting that will take me off road. In that case, the load will not be split 50/50 across both tires a lot of the time. So, by having 4,000 lb tires in a setting that would usually call for 3,100 lb tires, you are safer when the load on a given tire jumps to around 4,000 lb due to undulating terrain.

That's my theory anyway :h

Bert

You can think or rationalize the legal meaning of GVWR anyway you want, but I contend that the GVWR on that FMVSS sticker on your door is a certification as to the "MIMIMUM SAFETY" standards for performance of your vehicles braking system and exceeding that number means you are "NOT OPERATING YOUR VEHICLE IN A SAFE MANNER".

Larry

Toyo MTs are 3950lb for the 295-70-17 size. Not sure about other sizes but that's about the closest to 4k if we for a 17" tire.
I have them on my Ram and so far they are a great tire. Not great great life since I got them siped and hauled a 4klb camper but they are solid. Have beat them up pretty bad on rocky roads with the camper and no flats.

rhagfo wrote:
So the stock tires if 265/75-16 are rated at 3,195# which is 12,780# got 6,390# on the rear axle. If you go to 18" rims you can get higher capacity.
Not that you would want to,
But the 17" rim were a loss of capacity! If I went to 17" from 16" I would loose 220# of capacity per tire!

It turns out that 17" rims are a bugger to find high capacity tires for. My stock rims are 20" but I wanted to replace them with steel rims for the off road stuff (cast aluminum and chains don't get along very well). But, it turns out that if I want to go steel, I have to get 18" or 20" rims. Toyo has some 18" and 20" tires that are rated for 4,080 lb.

Bert

So the stock tires if 265/75-16 are rated at 3,195# which is 12,780# got 6,390# on the rear axle. If you go to 18" rims you can get higher capacity.
Not that you would want to,
But the 17" rim were a loss of capacity! If I went to 17" from 16" I would loose 220# of capacity per tire!

Miles Away wrote:
Bert:
I understand. Be careful that you don't exceed your vehicle GVWR as that is an established (legal) limit and is not changed by different tires, springs, airbags or just about anything else. To keep it legal, stay with what you have, aired up to 80 psi (if that is the max psi for your tires)and you should not have any issues.

That's what I used to think as well, but if you check the laws, you will not find a single instance in the US or Canada where the manufacturer's GVWR is the legal limit for any vehicle. Most jurisdictions state that you can tow or load up your vehicle with anything you want as long as it is "safe". They neglect to define "safe", though. So, that's why I would like to have 4,000 lb tires. I will hit the limit of my truck long before I hit the limit of my tires thus reducing the likelihood that my vehicle will be labeled as being "unsafe".

It is strictly bureaucratic so there is little or no logic to it. But, it is the law.

There is some logic to my madness, though. We tend to look at our tires and think that as long as each tire's capacity is greater than half the load on the axle, then we are good to go. After all, half of the axle's load is on each tire, right? That's true if you are driving on level roads. I am considering using my TV in a more commercial setting that will take me off road. In that case, the load will not be split 50/50 across both tires a lot of the time. So, by having 4,000 lb tires in a setting that would usually call for 3,100 lb tires, you are safer when the load on a given tire jumps to around 4,000 lb due to undulating terrain.

That's my theory anyway :h

Bert

BertP wrote:
Miles Away - I have a Dodge 3500 SRW. I am looking for higher capacity tires to give me a margin of safety and keep me well within legal limits. Since the tire capacity is generally used today to determine if a vehicle is safe or not, having 8,000 lb worth of tire capacity helps ensure that I will never get close to that limit.

Bedlam - After I wrote the first post, I found out that 4,000 lb 17" tires are rare. You can, however, get 4,000 lb tires in 18" and 20". I don't know yet how many there are but Toyo has at least one model.

Bert

Bert:
I understand. Be careful that you don't exceed your vehicle GVWR as that is an established (legal) limit and is not changed by different tires, springs, airbags or just about anything else. To keep it legal, stay with what you have, aired up to 80 psi (if that is the max psi for your tires)and you should not have any issues.