Community Forums

Fool · 10-09-2012, 03:51 PM

I'm a newbie...confusion and contradictions abound when trying to determine how big a 5th wheel I can pull..within the published ratings. I'm working on the RAM Job Rating worksheet to try and sort this out. There is no problem with the towing capability....the problem arises in the "payload" (if I am calculating it correctly). I'm finding that the max payload of 9600lbs is restricting me to a GVWR of 8600 for the 5th wheel. The worksheet uses 25% of GVWR to determine king pin weight.

Does this seem correct...or am I doing something wrong. I'm sure I've seen larger rigs being pulled by 2500's....

Any help would be appreciated...Is there an "expert" website I could go to...

Thanks

TXiceman · 10-09-2012, 08:12 PM

Typical 5er will run 18 to 22% of the trailer GVWR for a pin weight...some as high as 25%.

The only way to know for sure is to get an actual loaded weight of the truck, full passengers, full fuel, camping accessories, hitch in the bed.

GVWR - loaded truck = max loaded trailer pin weight.

A 3/4 ton will always be limited by the GVWR before it reaches GCWR.

Why not step up to a 1 ton SRW or a DRW for the capacity to tow a larger trailer.

My F350 DRW has a GVWR of 13,300# and weighs 8810# wet and loaded. So I have 4420# max for a pin load.

Ken

Fool · 10-10-2012, 07:20 AM

Thanks Ken,
The thought has crossed my mind....just trying to optimize costs and actual trailer needs...not a full timer, so wanted to keep around 30', but the payload issue for the truck is putting a crimp in my plan. Will keep investigating...
Fool
Fellow Cypress resident...now past resident

Brett B · 10-10-2012, 07:49 AM

Ken, just an additional data point for you. I own a 2005 Ram 2500 Quad Cab Diesel and I tow a 2010 Keystone Montana Mountaineer 347 THT with no trouble. I have it set up with top of the line tires and air bags. I believe my trailer weight is in the 11,000 # bracket dry. The rig is very stable. The Cummins diesel offers plenty of power and torque as well.

BTW ... I have raised my trailer height by two inches to accomodate the fact that the truck is a 4x4. This has allowed me to keep the loading equal across the tandem axle trailer.

Hope this helps.

RustyJC · 10-10-2012, 09:09 AM

That's all fine and well, but the original poster specifically stated that he wanted to tow "...within the published ratings". Is your rig exceeding Dodge's rated GVWR? Have you had it on the scales with the RV and truck loaded in the configuration you're heading down the road?

By the way, dry weights of an RV are meaningless. What is the RV's GVWR? That's the key number to use in sizing a tow vehicle.

Rusty

JIMNLIN · 10-10-2012, 07:48 PM

Quote:

I'm finding that the max payload of 9600lbs is restricting me to a GVWR of 8600 for the 5th wheel. The worksheet uses 25% of GVWR to determine king pin weight.

Does this seem correct...or am I doing something wrong. I'm sure I've seen larger rigs being pulled by 2500's....

Those folks, as most folks, may be using the trucks 6000 RAWR to figure rear axle loads instead of using GVWR to figure the rear axle load (payload). Front axle carries little to no pin weight from a 5th wheel trailer. Using axle/tire load limits to carry payload requires weighing the trucks front and rear axles seperatly.

My 2500 Dodge/Cummins pulls a 11200 lb 5er. My ready to travel rear axle load ranges from 5100-5400 lbs depending on how much "stuff" we load in the trailer (long trip vs short trip). My truck is 600-900 lbs under rear axle/tire load ratings and 100-400 lbs over the trucks GVWR. Do not exceed the trucks axle/tire load ratings as those are the big safety issue numbers.

As you see the worksheet use GVWR to figure pin weight loading on the trucks rear axle which is fine as its also a safe way to figure loads on the trucks axle/tires but sure limits using the trucks full potential your paying for.

TXiceman · 10-10-2012, 07:59 PM

Quote:

Originally Posted by JIMNLIN

Those folks, as most folks, may be using the trucks 6000 RAWR to figure rear axle loads instead of using GVWR to figure the rear axle load (payload). Front axle carries little to no pin weight from a 5th wheel trailer. Using axle/tire load limits to carry payload requires weighing the trucks front and rear axles seperatly.
.

And fully read the manufacturers tow ratings, footnotes and all. It says you are not to exceed ANY OF THE RATINGS, GVWR, GCWR or GAWR. They do not give the option of selecting which of the ratings you want to follow. The OP did say he wanted to be within manufacturers ratings.....

Ken

CD · 10-10-2012, 10:28 PM

Quote:

Originally Posted by Brett B

Ken, just an additional data point for you. I own a 2005 Ram 2500 Quad Cab Diesel and I tow a 2010 Keystone Montana Mountaineer 347 THT with no trouble. I have it set up with top of the line tires and air bags. I believe my trailer weight is in the 11,000 # bracket dry. The rig is very stable. The Cummins diesel offers plenty of power and torque as well.

BTW ... I have raised my trailer height by two inches to accomodate the fact that the truck is a 4x4. This has allowed me to keep the loading equal across the tandem axle trailer.

Hope this helps.

If your trailer is in fact 11K dry, I am betting that you are 13/14K loaded if not more. IMO from a safty point of view, it is more important to be able to handle/stop the trailer than how fast you can pull it.
Here is what CAN happen with an undersize TV.

Cat320 · 10-11-2012, 06:36 PM

Your truck will have a Tire and Loading Information sticker on the driver's side frame, you should see it when you open the door. It will spell out the cargo capacity for THAT truck to the nearest one pound.

Gary - K7GLD · 10-11-2012, 07:00 PM

YUP - always lotsa folks with oversize bulgemobiles popping in stating how well they can PULL an oversized rig - but they shy away from what the manufacturer CLEARLY states is the load rating - safe RVing involves LOTS more than simply whether the tow vehicle can PULL the load - it also involves steering, stopping - and unexpected emergency maneuvers.

You know - all the stuff the overloaded RVers tend to ignore ...

We tow a '88 KIT 5er - 24 foot version - and the pin weight is 1200 lbs. With the added in-bed fuel/tool tank, 5th wheel hitch, and other down-the-road RV junk in the bed, we're right at the rated load for our '02 Dodge/Cummins 2500 2WD...

JIMNLIN · 10-11-2012, 08:02 PM

Quote:

Originally Posted by TXiceman

And fully read the manufacturers tow ratings, footnotes and all. It says you are not to exceed ANY OF THE RATINGS, GVWR, GCWR or GAWR. They do not give the option of selecting which of the ratings you want to follow. The OP did say he wanted to be within manufacturers ratings.....

Ken

Looks like you want to argue the same old point ad nauseum .... so here we go.
Using the trucks RAWR to figure loads on the rear axle is within the manufactures ratings and is safe/legal. The truck owners may choose any of the many wight numbers to use for figuring axle loads.

Using the truck manufacturers GVWR/GCWR is safe also but has no legal status in how much load the trucks axle/tires can legally carry.

If the OP chooses to use all the many numbers to figure how much pin weight his truck may carry or a GVWR worksheet that fine. He simply is short changing himself of his trucks actual ability to safely carry axle loads from the pin weight.

And yes its his decission.

elkhornsun · 10-12-2012, 06:54 PM

The GCWR figure is the one that derives from the capabilities of the engine, drive train, suspension, frame, axles, and rims and tires, in calculating the maximum tow weight. With the current 2500HD trucks with the diesel engine it permits towing up to 17,500 lb. 5th wheel. King pin weight with that trailer load would be around 4300 lbs. plus the weight of the king pin itself. Maximum payload with the 2500HD in stock configuration is 4192 so allowing for a 200 lb. max king pin weight it can handle a 5th-wheel weighing in at 15,968 "wet" or fully loaded. With a 3500HD Dooley with the diesel engine the 5th-wheel could weigh up to 21,500 lbs.

There are trailering guides published by Ford and GM and Dodge which provide these numbers. Does anyone really think that they would incur the liability and goodwill problems if people pulled these loads and experienced safety or reliability problems?

Brett B · 10-13-2012, 06:27 AM

Very well summarized. Thank you.

RustyJC · 10-13-2012, 06:36 AM

Please be careful in using the manufacturer's towing guides. The trailer towing capacity and payload capacity quoted in these guides is based on a base truck's curb weight with only a 150 lb driver. Every pound you add to the truck's base curb weight (a heavier driver, passengers, pets, cargo, options, accessories, the 5th wheel hitch, etc.) must be deducted from the trailer towing capacity and payload capacity. Actual curb weights can be as much as 1,000 lbs or more greater than the base curb weight used in the manufacturer's calculations.

Rusty