Calculating tongue weight

[Spindrift]

I finally had a chance to weigh my rig prior to our last trip out. I was surprised to learn that my tongue weight was approx. 9% of trailer weight, even after I had front loaded what I thought to be more than enough cargo. Is there anything I can do, other than placing lead bars in my front storage compartment, that will increase my tongue weight?

The dealer where I purchased my Reese Dual Cam HP said that tongue weight could be as low as 7% of the trailer weight. I'm finding that my current 9% isn't adequate and I would like to be more towards the top end of the 10 - 13% range. I would like the trailer to track a little better than what I currently experience, which isn't bad at all considering I know that technically, a 34' trailer is a little long for my Burb's wheelbase.

I believe what's contributing most to the challenge of increasing tongue weight is the style of the TT. The Cougar has a rear bedroom slide-out which, more than likely, is placing a disproportionate amount of weight on the rear of the TT. In Keystone's infinite wisdom, all three tanks are located between the TT axles and the end of the TT so loading up with fresh water is out of the question.

I weighed my rig on a 3 platform CAT scale. These are the numbers:

TV and TT
Steer Axle 3,860 lb.
Drive Axle 5,340 lb.
Trailer Axle 8,660 lb.
GROSS WEIGHT 17,860 lb.

TV
Steer Axle 3,920 lb.
Drive Axle 4,420 lb.
Trailer Axle 00 lb.
GROSS WEIGHT 8,340 lb.

17,860 (TV and TT) minus 8,340 (TV) equals 9,520 lb.
5,340 (TV/TT Drive axle) minus 4,420(TV Drive Axle) equals 920 lb.
920 lb. divided by 9,520 lb. equals 9.7%

I like to round down.

Based upon these numbers, is 920 lb. the "true" tongue weight?

[ 08-25-2004, 05:41 PM: Message edited by: Spindrift ]

[David Utz]

TV and TT
Steer Axle 3,860 lb.
Drive Axle 5,340 lb.
Trailer Axle 8,660 lb.
GROSS WEIGHT 17,860 lb.

TV
Steer Axle 3,920 lb.
Drive Axle 4,420 lb.
Trailer Axle 00 lb.
GROSS WEIGHT 8,340 lb.

GCVW = 17860 lbs.
TV GVW = 8340 lbs.
GCVW - TV GVW = TT GVW
17860 - 8340 = 9520 lbs.
TT GVW - TT Axle = TT Tongue weight.
9520 - 8660 = 860 lbs. tongue weight.
tongue weight / TT GVW = %tongue weight.
860 / 9520 = 0.090 = 9%

[Turbine Doc]

Got room for a propane bottle rack/water tank up there, or maybe a tool box & spare tire mount, usualy not to much "extra room" up there just brainstorming

[Spindrift]

I'm thinking about an extra tank for the WMI. Would love to re-work the forward storage compartment. Right now, designed more for the bulky items (folding chairs and tables) that are light in weight. I'll keep scratchin' the pumpkin.

[sturgeon-phish]

What about one of those wedge shaped cargo boxes that are designed for the front of trailers? More storage and forward weight.

[Diesel Freak]

As pointed out earlier, your tongue weight is actually 60 lbs less than you thought. You need to account for the weight that transfered from your front axle to your rear axle with the trailer hitched up. That being said, a few items I have seen after 100's of thousands of miles towing: Make certain you have your rear wheels of the tow rig aired up to the maximum amount stamped on the tire, don't go by GM spec's. Also make sure the tires on the trailer are at their max as well. If you have already done this you can try changing the tires on the trailer to a tire with a higher load carrying capacity. The reason is sidewall flex which translates into trailer sway. If you haven't already installed one, mount a sway control on the trailer, that will definitely help. I'm assuming you are towing the trailer at or very near level, if not that will make a sizeable difference. At 9% tongue weight you are pretty dang close to the optimal 10% rating. I have found that to be a "guideline number" There are many other factors involving how the trailer tows: axle placement on the trailer, trailer tires, overall profile of the trailer, length of the trailer, etc. I've pulled some bumper pulls with the tongue weight down around 5% that pulled great, other trailers I've had 15-20% tongue weight that pulled like crap.

One thing you can think about if you want to move weight is the trailer batteries. They are very heavy, often installed towards the rear, and pretty easy to move to the tongue area. Or you can consider adding a couple of batteries to the tongue. Seems you can never have enough batteries when you're dry camping ;) I have 10 batteries in my motorhome :rolleyes:

Sorry for the long post, hope it helps.
Jerry