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View Full Version : Exceeding TV towing capacity/rating


jwv
12-30-2011, 02:50 PM
Fact:
tens of thousands pull 15- 16k 5th wheels with 3/4 tons with no problems.

SteveC7010
12-30-2011, 03:14 PM
tens of thousands pull 15- 16k 5th wheels with 3/4 tons with no problems.

And where does this "fact" come from?

Even the poster who was originally firmly convinced that pulling a heavy trailer with a 3/4 ton truck was OK has now at least conceded that there are some good reasons that this may not be as safe as one might think.

Continuously exceeding the payload of a truck by 50 to 100% (or more) is not a recipe for "no problems"; it pretty much guarantees that the rig is unsafe. It may not fail today or tomorrow, but it will fail.

If you are going to claim that overloading a truck is safe and will not cause problems, perhaps you could at least give us some credible proof of same.

2011 keystone
12-30-2011, 03:23 PM
Can we all say BEATING A DEAD HORSE:yawn: Dont get me wrong steve I agree with you that there are a lot of very overloaded trucks on the road and that this is VERY unsafe at best. But you will never convince everyone. That because it can be done does not mean it should be done.

Paddler
12-30-2011, 04:42 PM
The disclaimer: I have no supporting facts for the following.

Last century almost everything was built with a 20% safety margin. An example: A device was rated to lift 100 lbs it would have been designed to lift 120 lbs. This insured the device would lift the rated load (quality control) and usually made for a robust product. Which was good for the manufacturer's reputation but it did cost more to build.

Times have changed, nowdays almost everything is built to a price point thus a device rated to lift 100 lbs might do it, but the device has very little reserve capacity. So from my perspective if your truck has a payload capacity of 2000 lbs...don't count on it to handle 2400 lbs repeatly. The bean counters have forced the engineers to meet the specification and no more.

Believe me, I know the pain of being under-trucked, spending 50K on my dream RV only to later discover I'd need to spend another 60K on the dually. :( That put my retirement dreams on hold for a year or so. But it is also part the reason why I'll usually take the time to review the numbers on a new poster's questions about TV & TT matchups. If I can help someone not make the costly mistakes I have made...

mhs4771
12-30-2011, 05:28 PM
Prime example of the above post: Just look at the problems with Tires and not just Keystone, but visit just about any forum and you'll find threads about tire problems because the Mfrs are putting the bare minimum rated tires on these rigs. Enough said

jwv
12-31-2011, 06:08 AM
any stories from those who have pulled 16k gvwr and heavier 5th wheels for several years and several thousand miles ? did you have to replace rear springs and shocks ? did your truck fall apart ?

smiller
12-31-2011, 08:10 AM
Not too likely the truck would fall apart or anything as the drivetrain of 3/4 vs. 1-ton trucks are often identical (the diesel versions at least), the real limiting factor for a 5th wheel is the rear axle load, specifically the tires. A 15-16k 5th wheel is probably going to have a pin weight that would generate a load higher than any two 'E'-range tires are rated for and that is not open to interpretation or opinion, it's simply a matter of what the scale says vs. the tire weight capacity. You can press a lot of things but tire load ratings are not one of them. Grossly overloading a tire is probably one of the single most dangerous things you can do.

Jim W
12-31-2011, 08:21 AM
any stories from those who have pulled 16k gvwr and heavier 5th wheels for several years and several thousand miles ? did you have to replace rear springs and shocks ? did your truck fall apart ?

I have own two 2500HD trucks one gas and the other a Cummins diesel. Both have been rated to tow a maximum #12,450 LBS trailer with a #20,000 GCWR. I have never towed nor would I ever tow over these ratings. Not only do you need to consider the following components; axles, tires, wheels, transmission, differential, drive shaft, bearings, springs and frames design life and loading you also need to consider stopping this mass in a controlled and safe manner.
When a vehicle is designed and tested all of these parameters are considered and tested to achieve a safe vehicle weight rating for towing. If a 2500HD truck could tow the same load as a 3500 DRW or a 4500/5500 C&C vehicle why build them. The manufacture could raise the asking price of a 2500HD and make more profit off of just one model of vehicle. The manufacture would not need to inventory all of the other components that are required for a 3500HD DRW or a 4500/5500 C&C vehicle. Thus saving money and making more profit on larger economical buying of one set of components.

BTW, I am a retired engineer from a large equippment manufacture in the mid-west that use to design and test tractors.
Jim W.

smiller
12-31-2011, 08:44 AM
Not only do you need to consider the following components; axles, tires, wheels, transmission, differential, drive shaft, bearings, springs and frames ...But that's how I think a lot of people get confused on this subject. For instance in the Dodge world (not sure about GM) all of the things you mentioned are absolutely identical on the 3/4 SRW and 1-ton DRW trucks, so people sometimes assume that their towing capacity is the same... forgetting the critical little matter of two extra rear tires! It doesn't matter if the truck can handle the load if the tires cannot.