Advantages getting tires that exceed GAWR (rear)?

[Oregonbound]

aahhhggg....I did finally check the sticker on THE DOOR (not the door chassis) and sure enough the GAWR (rear) is 6200#. I called Dodge Body Builder #....waste of time. Person sounded very confused even though I gave them exactly what I have including VIN #. Told me the GAWR (rear) is 7000#.

Relatedly, is anyone else having problems with the "Truck" and "Van" links at http://www.rambodybuilder.com/year.pdf ?

Thanks for everyone's help with a newbie. I really appreciate this forum and the friendly and helpful folks here. The Internet is amazing....what did we do before we had it? - hard to even imagine.

[SmokeyWren]

Originally Posted by Oregonbound

Not sure what "FMVSS" means(?).

Federal Motor Vehicle Safety Standards (FMVSS)

Big Brother is watching over you.

There are a bunch of different standards, including:

Originally Posted by FMVSS

Standard No. 120 - Tire Selection and Rims for Motor Vehicles Other Than Passenger Cars - Multipurpose Passenger Vehicles, Trucks, Buses, Trailers, and Motorcycles, to Rims for use on those vehicles, and to Non-Pneumatic Spare Tire Assemblies for use on those vehicles
(Effective 8-1-76)

This standard specifies tire and rim selection requirements and rim marking requirements. Its purpose is to provide safe operational performance by ensuring that vehicles to which it applies are equipped with tires of adequate size and load rating and with rims of appropriate size, type designation, and manufacturer identification.

For more detail, look up FMVSS Standard No. 120

[wingnut60]

Oregonbound,
The AXLE may have a higher rating by itself than what Dodge lists. But they won't rate it higher than what the tires themselves will carry. Lots of Dana axles will rate higher by Dana than what the vehicle mfg will rate them, at least that is what I understand.
Joe

[JIMNLIN]

Not sure what "FMVSS" means(?). I'm going to call Dodge directly and am getting it in for service on Thursday so will ask then as well. Thanks

Just to add to what Smoky says about 49 CFR 571.120, this from paragraph;

S5.1.2 Except in the case of a vehicle which has a speed attainable in 3.2 kilometers of 80 kilometers per hour or less, the sum of the maximum load ratings of the tires fitted to an axle shall be not less than the gross axle weight rating (GAWR) of the axle system as specified on the vehicle's certification label required by 49 CFR part 567. '

This insures the truck comes from Dodge with the correct tires and rim load capacity per the GAWR's.
Click on the FMVSS of your choice for years of reading government safety requirements.
For 571.110 below 10000 lb GVWR vehicles and 571.120 above 10000 lb GVWR eCFR — Code of Federal Regulations

[elkhornsun]

The Ram trucks use the same AAM axles as GM and the axles and wheel bearings are rated at 10,900 lbs. load capacity. As per Ford Motor Co. -

"Gross Axle Weight Rating is determined by the minimum component of the axle system (axles, computer-selected springs, wheels, tires) of a specific vehicle."

No big deal to change the springs, wheels, tires and alter the GAWR for a truck, for the better or the worse. I changed the factory applied tires on my truck that were rated at 3195@80 PSI with ones rated at 3750@80 PSI. The new tires increased the load capacity by 1100 lbs. and improved handling.

The aftermarket equipment market exists to provide improvements to stock vehicles. It has been doing so for decades but it seems a lot of people are unaware of this.

[RustyJC]

The manufacturer-certified GAWR, however, doesn't change. It's still the rating shown on the driver's door sticker.

Rusty

[azdryheat]

It's all the same axle. Add a spring and heavier tires and the axle rating increases from a 3/4 ton to a 1 ton. Not talking dually here. Nothing in the axle changed. Brakes, shocks, and frame haven't changed. Notice how the axle rating just happens match the load capacity of the tires in most cases.

[Mekanic]

there is a one advantage to higher load rated tires And usually it is its puncture resistance to foreign objects. This is because usually the higher the load rating the higher the tire pressure rating and the thicker or tougher they make the reinforcements in the tire tread and sidewalls.
They MIGHT run cooler at he higher tire air pressure for the same given load.

[Oregonbound]

Originally Posted by JIMNLIN

Dodge shows the 3500 SRW up to a '12 model has a 6200 RAWR. In '13 it goes on up to 7000 lbs RAWR.

looking at Dodge specs shows the rear spring pack at 6500 lbs but with a 6200 RAWR. I think Dodge has a typo on some of their website spec charts.

Indeed. I spoke with a RAM rep. and we determined that the spec for RAWR on the truck's placard is incorrect (as far as axle rating). The RAWR is 6500#, not 6200# as indicated on the placard. He thought that they put the lower # on the placard because the OEM tires were rated for 6380# and they did not want forks to exceed the tire ratings.

Here's the actual email I received:

I found out your situation. While the axle and suspension is capable of 6500 lbs, the tires are only capable of 6200 Lbs [actually 6380 - my addition]. Why we did not explain that on the weight charts I do not know. And unfortunately, you cannot simply buy larger tires and upgrade. While technically you can do it, Chrysler will not provide a new label on the door with new ratings.
I hope this at least clarifies the situation.

[Ray,IN]

It's rather hard to out-think the design engineers. Operating any vehicle at or exceeding it's design limits will greatly shorten its lifespan and increase operation costs. Aftermarket companies do not concern themselves with vehicle longevity, that doesn't make them money, nor is why they are in business.
My advice, dance with the girl you brung.