weight

[janpaul]

I would like to get a ballpark figure on a safe max trailer weight for my setup if possible. I am in the process of setting my truck up with the following. 2005 2500HD  Duramax/Allison  373 Rear. B&W turnover ball and companion hitch, 51 gallon auxilliary fuel tank/toolbox, and possibility of 4 passengers plus driver. What would be a safe weight for towing out west to stay under when looking for a camper? I guess it would be GVWR of the camper, fully loaded. Thanks, Paul

 

[Gary RV_Wizard]

You need to start with the max tow rating for your truck and then subtract all the extra weight you are carrying. That will lead you to the available towing capacity, which you can match against the GVWR of the trailers you are considering.

Find the Chevy/GMC  towing specs HERE . Click on Trailering ta and scan down for the engine (etc) configuration of your truck. Note that there are separate ratings for ball hitch (conventional trailers) and fifth wheels. This info is for 2006 vehicles, but 2005 is identical for all practical purposes.

You are starting from somewhere between 14,200 and 15,400 lbs, depending on the details of your truck. You will need to figure out the weight of that fuel tank and fuel. Diesel weight per gallon varies with the season, but using 7 lbs/gallon will give you a fair estimate. Good luck on finding out your wife's weigh! 

We generally recommend staying well under the max load when towing in the Western mountains, but a turbo diesel can handle the steep grades pretty well. Downhill is another story...

 

[janpaul]

If I use 15,400 and allow 600 for the tank and 600 for four extra passengers(told wife her allowance is 105lbs. ha ha) that comes to 14200. I have seen you guys talk about percentage allowances and subtracting 20% would leave 11360. If I stay under 12000, would that be a good reference when looking? That seems reasonable because if we have extra passengers, they most likely will be smaller children, but normally my wife and one small child besides me.

 

[Gary RV_Wizard]

Subtract another 175 lbs for the hitch and related stuff, but Yes, I think 12,000 would be a very reasonable target for that tow vehicle.  Carl may disagree with me, but I think a 20% safety margin is ultra-conservative for your particular tow vehicle and I have no qualms about going to 12,000 in your case.  For the benefit of other readers, I will explain: if the truck was  powered with a small block gas engine and/or had a 4 speed automatic, I would not agree to stretch the 20% safety margin for western towing, but in my experience a diesel with a 5 or 6 speed is capable of handling severe terrain without eing overstressed.

 

[Carl L]

Subtract another 175 lbs for the hitch and related stuff, but Yes, I think 12,000 would be a very reasonable target for that tow vehicle.? Carl may disagree with me, but I think a 20% safety margin is ultra-conservative for your particular tow vehicle and I have no qualms about going to 12,000 in your case.? ?For the benefit of other readers, I will explain: if the truck was? powered with a small block gas engine and/or had a 4 speed automatic, I would not agree to stretch the 20% safety margin for western towing, but in my experience a diesel with a 5 or 6 speed is capable of handling severe terrain without eing overstressed.

I agree about the diesels, if for no other reason than you has wore me down at last.? ?;D? ? My reasoning was that 3% HP loss per 1000 feet elevation gain that a normally aspirated engine takes.? However, a turbo diesel is not normally aspirated, it has a supercharger and does not have to take the full  altitude hit.? ?Without that turbo it would take the hit in full.

But what the turbodiesel takes on the up hill run, it gives away on the downhill run because of its lack of engine braking.? ?If unit doesn't have some sort of add-on engine brake like a Jake Brake, it probably shouldn't be out west at all.? ?I would sure as hell hate to do the Grapevine, Lookout Pass, or Siskyou Pass with no engine brake -- and those are all Interstate highways.

In any case, there is no such thing as too much tow capacity, but there is, sure as shooting,  too little -- especially downhill.  If I am to err, I would err on the safe side.

 

[2006F350]

Carl,

Not all Turbo Diesels (from the factory) lack engine braking. On my 2006 F350 with the Powerstroke, when the Tow/Haul mode is activated, the engine will be used as a brake when you descelerate - towing or empty. I don't know the leading particulars of what exactly is happening, but last June, when crossing the Cumberland between Nashville and Knoxville (6%) on I40, the engine had no problem holding back my 10+ tons of rolling stock (TV and 5W) with very little brakeing on my part. I remember reading somewhere that since Ford (Powerstroke is by International) doesn't have a wastegate, and instead uses the EGR valve as a wastegate, when in tow/haul and foot off the accelerator, the EGR is electrically kept closed or such which makes the engine think it's an air compressor. If it didn't already to that, I would be the first person in line to add a jake brake to the truck - I wouldn't want to tackle grades greater than 5% without some assistance in the braking department.

Larry