I used to have a 1994 Dodge Ram 3500 Cummins/5 speed.
ALL of the manufacturers weight ratings were figured with 4.10 axle gearing and Load Range D tires. I replaced the tires with one size larger, and Load Range E.(On a side note, the one size larger tires corrected the speedometer error!)
When I titled the truck in Montana, the DMV clerk asked me what GVW (no, not RATING, actual Gross Vehicle Weight!) I wanted on it. I said "Oh, 14,000 sounds like a nice number." She said "No problem!"
So, regardless of what the door post data tag or the Owners Manual said, that truck was now LEGAL to be loaded to 14,000 lbs. Gross Vehicle Weight!
After towing a 32 foot triple slide fifth wheel for a couple of years of full time living, I decided to weigh it. It was under GAWR for all axles, under GVWR for the truck and trailer, under the registered GVW for the truck, but OVER the truck GCWR for the combination by a little over 3,000 lbs.!
Of course, the GCWR for a 1994 Dodge was stupidly low! It went up every year after that, with little or no changes to the truck. Ford, Dodge, and GM were playing a numbers game back then.
But anyway, I could make the truck LEGAL to 14,000 lbs. GVW. There is no way I could make the truck LEGAL to go 60 MPH in a 55 MPH zone.
THAT is the difference!
Oh, wait, there MIGHT be ways to make it legal to go 60 in a 55:
1. Have "Amateur Radio" call sign license plates. In an authorized emergency, it MAY be legal to exceed the posted speed limit.
2. Have "National Guard" license plates. In an authorized emergency it MAY be legal to exceed the posted limit.
4. Have "Volunteer Fireman" placards on your vehicle. In an authorized emergency, it MAY be legal to exceed the posted limit.
Of course, it depends on the rules in YOUR state. There may even be other placards/license plates that will allow you to exceed the speed limit in certain situations.
But, back to the '94 Dodge. Even at 3000 lbs. + over GCWR, nothing bent, nothing broke, there were no accidents or incidents, and nobody died or was injured.
It is one of those "YOU have to make up your own mind what to do!" scenarios. I certainly won't tell you it is OK! I can only describe what I have done.
Good luck.
