Trailer Weight calculation

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.

starfish

Active member
Joined
Jul 27, 2006
Posts
34
Location
Point Mugu
I've been looking through this forum and I've seen a ton of threads like the one I'm putting out.

I just bought a 2006 Dodge Ram 1500 4x4 SB w/Hemi, 5 speed auto w/lock converter, 3.92 ratio.  Everything I've seen says that I can tow 8500 lbs, until today.  I was looking at a towing guide link from one of the threads that said my max towing weight was 7400 lbs, because of the 20" rims.  My wife and I have found the perfect TT:  Its a 2007 Wildwood 250RSL.  It has rear queen slide and quad bunks in the front.  The dry weight is 5360 lbs, while the GVWR is 7500 lbs. 

Is this too much trailer for my truck?  I have plenty of HP and torque, but what do you guys think?  How do other factors fit, like stuff in the bed of the truck?  Does the 15-20% rule apply with this truck? ???
 

Lowell

Well-known member
Joined
Aug 15, 2005
Posts
2,221
Location
Tempe, AZ
Starfish,
See my post from today on getting my actual trailer weights under trailers and fifthwheels.  I have the same truck you do except mine is a 2005.  I have 20 inch tires and the 3.92 rear end which is standard when they go to the 20 inch tires.  My truck is rated for pulling up to an 8500lb trailer and a gross combined vehicle weight of 14,000 lbs.  I have a Cherokee Light 28 ft Tt that weighs 5300 lbs empty and 6120 lbs loaded.  I recently pulled the trailer through western Colorado and had no problems at all.  The truck was very capable of climbing the 6 & 7% grades at a reasonable pace. On that trip there was only the wife and I, no gradchildren, and my fresh water tank was empty. Hope this give yousome encouragement.
Jake
 

starfish

Active member
Joined
Jul 27, 2006
Posts
34
Location
Point Mugu
Thanks Jake.  That makes me feel a little better.  My wife has her heart set on the Wildwood, and the price is right.
 

Lowell

Well-known member
Joined
Aug 15, 2005
Posts
2,221
Location
Tempe, AZ
I live in Tempe, AZ.  On the trip to Ridgeway Colorado, I averaged 11.2 mpg overall which included 1080 miles of towing and 600 miles of of driving the truck on back forest roads and highways.  Towing on the Interstates, I usually drive about 60 mph in the tow-haul mode. When driving the truck alone I usually drive the speed limit or just over.  ;) Generally, I get about 14-15 mpg in town which is a combination of 45mph streets and 65mph freeways.  On trips with just the truck, I get a solid 17 mpg. I think I am somewhere in the range of 9 -9.5 mpg towing only. When my truck was new and I pulled the trailer and didn't want to exceed 55 mph for the first 500 miles of towing, I got about 12 mpg towing. Speed make a difference.
Jake
 

Carl L

Moderator Emeritus
Joined
Mar 14, 2005
Posts
7,239
Location
west Los Angeles
starfish said:
I've been looking through this forum and I've seen a ton of threads like the one I'm putting out.

I just bought a 2006 Dodge Ram 1500 4x4 SB w/Hemi, 5 speed auto w/lock converter, 3.92 ratio.? Everything I've seen says that I can tow 8500 lbs, until today.? I was looking at a towing guide link from one of the threads that said my max towing weight was 7400 lbs, because of the 20" rims.? My wife and I have found the perfect TT:? Its a 2007 Wildwood 250RSL.? It has rear queen slide and quad bunks in the front.? The dry weight is 5360 lbs, while the GVWR is 7500 lbs.?

Is this too much trailer for my truck?? I have plenty of HP and torque, but what do you guys think?? How do other factors fit, like stuff in the bed of the truck?? Does the 15-20% rule apply with this truck? ???

Assuming the correctness of your 7400 figure, which seems reasonable for a 1550/150 unit that trailer is too heavy.  Other factors in tow rating?  Well there is transmission, drive train, rear end, suspension, and brakes -- especially brakes.  Does the 15-20% safety factor apply?  Yup, if you tow in the mountain or pacfiic west.    Why?  Well  your engine loses 3% of HP per 1000 feet of elevation.  At 8000 foot, the altitude of a lot of passes, you lose 24% of your rated HP unless you have a supercharged engine.  However, if you tow around the east, then 10% is your safety factor.

Face it, a 1500 is a light duty truck be it Dodge, GMC, or a 150 Ford.  It is a compromise between a sedan and a load hauler.
 

starfish

Active member
Joined
Jul 27, 2006
Posts
34
Location
Point Mugu
Carl,

Thanks for the input.  Is the 15-20% safety factor just for HP?  What I mean is, if you have the horse power, is 10% safety factor good?
 

Lowell

Well-known member
Joined
Aug 15, 2005
Posts
2,221
Location
Tempe, AZ
Carl,
I have the same truck as he does and I had absolutely no problems pulling my trailer through the passes in Colorado including one at 10,600 ft. Today's newer trucks with their computers do a pretty good job adjusting for the altitude.  The trailer he is talking about weighs only 5300 lbs dry, about the same as mine. Even when loaded, won't he still have a pretty good margin left? 
Jake
 

starfish

Active member
Joined
Jul 27, 2006
Posts
34
Location
Point Mugu
We found a Trail-Cruiser 23SB with a GVWR of 5800 lbs, well within the capability of my Dodge.  The price is higher and the floor plan is a little different, but I think it will be fine.

Does $850 sound okay for Equalizer/stabilizer bar and brake control?
 

Gary RV_Wizard

Site Team
Joined
Feb 2, 2005
Posts
74,979
Location
At my Silver Springs FL home
Does $850 sound okay for Equalizer/stabilizer bar and brake control?

That sounds like the typical dealer "package" price.  You might do a little better if you shop around local hitch shops, but if the dealer will take care of everything for that price its OK.  I strongly recommend that you get the Tekonsha Prodigy brake controller, though, and they may balk at including that one in the package price .  It's a bit more expensive than the ones typically included, but very much a superior product to the Drawtite Activator they usually foist on newbies. The Drawtite version of the Prodigy is OK, though, and so is the Intelli-stop.
 

Carl L

Moderator Emeritus
Joined
Mar 14, 2005
Posts
7,239
Location
west Los Angeles
starfish said:
Carl,

Thanks for the input.? Is the 15-20% safety factor just for HP?? What I mean is, if you have the horse power, is 10% safety factor good?

No.  Even been on a miles long downgrade of 6-8%?  Like Lookout Pass, The Grapevine, Siskyou Pass, Towne Pass or Tioga Pass?    Your transmission and brakes are what holds your speed down below runaway speeds. 

 

starfish

Active member
Joined
Jul 27, 2006
Posts
34
Location
Point Mugu
Roger.  I just bought a Trail-Cruiser 23SB.  The GVWR is under 5300 lbs.  This is Well within the capabilities and safety marigin for my truck.  The price was a little higher than the Wildwood we were looking at, but what the hell.
 

starfish

Active member
Joined
Jul 27, 2006
Posts
34
Location
Point Mugu
RV Roamer said:
? I strongly recommend that you get the Tekonsha Prodigy brake controller, though, and they may balk at including that one in the package price .?

I did get the Tekonsha Prodigy, hitch, and wiring thrown in...at no charge.  I may have been able to get them down a little more on the price of the trailer, but I think I did well.  My wife is happy, and I can afford what I got.
 

Latest posts

Forum statistics

Threads
121,176
Posts
1,220,434
Members
126,184
Latest member
Mgelmi
Top Bottom