downtheroad
Pacific Northwest
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Joined: 02/18/2003
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Often hotly debated topic...Like skip said, it's also about your own comfort level and you won't know that until you get on the road and see how it feels.
On a previous trailer, I was within the numbers (using the trailers GVWR)...forget dry weight - it's meaningless, but after a couple of trips I just wasn't liking how it towed so that resulted in a new tow vehicle with more of a cushion within the numbers.
My advice: forget dry weight numbers and second, don't jam yourself too close to the GVWR'ings.
"If we couldn't laugh we would all go insane"
GMC Duramax/Allison (LBZ)
Komfort .... Our Rig Picture>>Click.
Reese Dual Cam HP
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cephas02
missouri
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Joined: 07/24/2010
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Replacing the tow vehicle is what I'd to avoid- I like my truck for everyday purposes, so I need the TT to be within it's limitations. It's a chicken/egg thing- I need to have some kind of target dry weight to know what to look for in a camper. Once I find one I like, I'll definitely weigh it to make sure I'm under the GCWR and trailer capacity numbers. I just want to make sure I'm not setting myself up for problems down the road if my choices take me up near my maximum rated capacities.
I'm think going to run down the highway to a truck stop and get my GVW.
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mowermech
Billings, MT
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Joined: 06/28/2003
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I can only relate personal experience.
When full-timing in a fifth wheel, I bought a 1 ton dually, and never looked back.
I finally (after reading many "weight police" posts on these forums) decided I really should weigh the rig, so on the last trip I went across the Flying J scales.
I discovered I was UNDER GAWR (Front), UNDER GAWR (Rear), UNDER GVWR, WAY Under registered GVW...
BUT, the GCWR listed in the Owner's Manual is 18,000 lbs. The actual GCW was 21,180!
I had no accidents, nothing broke, nobody died, and there was no trail of death destruction and mayhem behind me. The truck handled mountain passes with no trouble.
All you can do is hook up, load up, and try it. If you don't like it, get a bigger tow vehicle.
Good luck.
CM1, USN (RET)
'94 Dodge 3500 4X2 CTD, 5 speed, 4.10 LS diff., Jacobs Rambrake, 275,000 Miles
'95 Tioga 29H Ford-based Class C
Daily driver: 2005 Jeep Grand Cherokee Hemi
Toad: 2006 Jeep Rubicon LJ
"When seconds count, help is only minutes away!"
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rgrimm
Florida
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Joined: 06/25/2010
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cephas02 - Yes - Get YOUR Truck weighed at a local CAT Scale with you in it and a Full tank of fuel. Now subtract that number (real weight of your Truck) from the GVWR that is posted on the drivers door of your Truck. Now you have what 'PAYLOAD' you have left. Payload is additional passengers, cargo you add to the Cab or bed of the Truck AND what's left is for the Tongue weight of any trailer you are considering.
Here's an example - My 09 F150 numbers. My Trucks GVWR (on drivers door jam) is 7200#. While I have seen 'curb weights listed for my Truck betweek 5400 - 5600#'s the REAL weight of my truck with me (190) in it and a full tank of fuel (36 gal) is 6320#. So 7200 - 6320 = 880 .... Now this is a truck Rated at Pulling a Trailer of 11,200# and has a GCWR (Truck and Trailer) of 17,100#, but once my wife and some stuff gets added to the Cab of the Truck, I might have 700#'s left for a Trailer Tongue weight. So using a 10% Tongue weight average, a loaded Trailer around 7000# would put me right at my Trucks GVWR. So that 7000 Trailer is 37% less than my Tracks Trailer Rating and My Combined weight (GCVR) for the Truck and trailer would be around 13,000 - way under the 17,100 Truck Rating.
So my point is that a TV's GVWR (the one posted on the Door Sticker) is usually the First weight rating that gets violated and this is because our TV's usually weigh (basically empty) way more than we think.
So my suggestion to any 'can I tow' question is to FIRST weight YOUR TV loaded to Travel (all cargo and passengers - you, wife, kids, dog, cooler with snacks, etc) and then subtract that number from your TV's GVWR that is posted on the Drivers Door now you know the Tongue Weight you can handle without violating your TV's rating. That will dictate the Trailer weight.
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cephas02
missouri
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Joined: 07/24/2010
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First, I want to thank this forum and those who have posted replies. I've been trying for two weeks to get the kind of good info I've gotten here just this morning...
On Cat scales, my vehicle scaled 2960, 2300, 5260 (frnt, rear, total).
Mowermech, I think the bigger trucks probably build in more "fudge factor". I work for a utility company, drive larger trucks and have pulled small pieces of equipment and some heavy trailers, so I know the GVWR can be exceeded at times on some of the bigger TV's w/o catstrophic effects. I'm just unsure about about how my light little 1/2 ton will stand the strain.
Rgrimm, you make an excellent point, and I probably would have missed that if you hadn't pointed it out. With my GCWR at 12,000 lbs, I don't think I'll ever be able to reach my MTWR of 6700 lbs.
If I add 740 lbs of miscellaneous payload to the truck (for a total of 6000 lbs GVW), then my GCWR would limit me to a 6,000 lb GVW loaded trailer. If I assume 600 lbs of trailer weight is carried on the tongue, I'll be within 200 lbs of my GVWR (6800 lbs) on the TV, correct?
So I think my bottom line is this- I need to buy a camper that weighs less than 6,000 lbs fully loaded- propane tanks, battery, water in the tank, etc. etc. etc. If anyone sees something else I may be missing here, PLEASE comment further.
Thanks!
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BenK
SF BayArea
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Joined: 04/18/2002
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Boils down to personal philosophy on ratings and risk management (aka...gambling).
If you know enough to re-engineer your components, systems and setup, then the
ratings only matter if there are legal positions (laws) dictating.
If you don't know enough to re-engineer, then of course stick to the ratings.
Why I started this thread: clicky to: Ratings, terms and opinions of what they mean...
Because a buddies 88 year father retired (farming) and followed advice on this
forum. Got into a accident, won't tell me because they are embarrassed, bought
a bigger TV and are happy now.
There is more to what is visible on the various charts where folks will say the
limiting factor is the diff ratio, tranny, engine, etc, etc. Sure that is what
is clear, but there are hidden attributes. Like the frame sizing, or whether
there is a frame or a monocoque (unibody).
There are dialed in safety margins with the OEM ratings that has the lowest
level driver as the demographics.
Anyone who has to ask this type of question does not have the knowledge (yet) of
the metrics to re-engineer their setup. I'll not give the 'sure you can' type
of advice, but to provide the metrics and let them do the simple math and risk
management decision.
Best advice it to go out and weigh your setup axle by axle, both empty and fully
loaded ready to go camping.
The find the ratings and do the simple math and this is the visual representation
The the silly but meaningful or significant fine print where the OEMs
outline the basis for their ratings.
Like it is the 'curb' vehicle, which is the base with no options or
aka...stripper model....and....only one 150 lb driver. Most who actually
weigh their vehicles are surprised that they weigh more than the
published 'curb', therefore their MTWR isn't possible and still keep
to the GCWR.
No options, no cargo, no people, no pets, etc.
Just noodle that image and how any additional weight affects the
simple formula
Bottom line is that this isn't a CAN NOT do it,
but that the safety margins are lesser and the MTBF is now lower
and therefore warranty issues will become a greater issue down the road
Meaning the wheels won't instantly fall off...just sooner than if
within the OEM ratings.
-Ben Picture of my rig
1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...
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Ron Gratz
full time RVer
Senior Member
Joined: 12/27/2003
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The equation, B-A = How much I can tow, in the above post is flat wrong and can be very misleading.
By the given definitions:
B = Actual combined weight of Trailer and Tow Vehicle
A = Actual weight of Tow Vehicle
then
B-A = Actual weight of Trailer = "How much I can tow"
IOW, according to the equation, you "can tow" whatever the trailer happens to weigh.
You should ignore the equation and heed:
1) Actual Tow Vehicle Weight Must not exceed the TV's GVWR, and
2) Actual Combined Weight of Trailer and Tow Vehicle Must not exceed the GCWR.
Also, each axle load must not exceed its GAWR.
Ron
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blt2ski
Kirkland, Wa
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Joined: 03/15/2001
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I prefer to figure max tailer out by, wieghing loaded rig, take away from GVWR< this number divided by HW% needed equal max trailer wt.
By this, AY rig with say 1000 lbs remaining to the GVWR, divide by .10(10%) max trailer is 10K. If this is more than Bens number, use the smaller of. If it is 25% HW needed, still you have 1000 lbs of payload, max trailer is 4000 lbs!
If you have no payload after loading, you max trailer capacity is ZIPPO, zilch, nada, nothing.......
I also take the max trailer I want to pull with any given rig to be 2x the GRAWR. So for the OP with atwhat appears to be a typical half ton style truck, these range from a 3000-4000 GRAWR, max trailer would be 6000-8000 lbs behind the rig, Assuming as mentioned, I can keep the axel wts in check. along with power, gears in trans and axel to meet my performance spec. Hence why I personally do not like to follow manufactures GVWR, as they seem to follow the soon to be new SAE specs, with a max grade % of 12-15%, I go up low 20% grade frequently enough to NOT trust manufactures GCWR;s.
marty
05 Chev CC D/A LS Dooley
92 Navistar dump truck, 7.3L 7 sp, 4.33 gears with a Detroit no spin
00 Chev C2500, V5700, 4L80E, 4.10, base truck, no options!
92 Red-e-haul 12K equipment trailer
3 Single axle utility trailers
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Ron Gratz
full time RVer
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Joined: 12/27/2003
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blt2ski wrote:I also take the max trailer I want to pull with any given rig to be 2x the GRAWR. So for the OP with atwhat appears to be a typical half ton style truck, these range from a 3000-4000 GRAWR, max trailer would be 6000-8000 lbs behind the rig, Assuming as mentioned, I can keep the axel wts in check.---
Marty, the OP's truck probably as a rear GAWR around 3750#. So, would you advise that he can prudently tow a 7500# trailer.
GMC's "Maximum Trailer Weight" for his truck is 6700#; which realistically means his maximum TT weight would be limited to about 6000#. Your formula would put him about 25% over the manufacturer's specification.
Perhaps you formula is okay for a Navistar dump truck -- but do you really think it is okay for the OP?
Ron
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LarryJM
NoVa
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Joined: 11/09/2007
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Sailbad wrote:You are looking at the correct rating. BUT you need to be looking at the GVW when shopping for a trailer. That's probably going to put you in a smaller trailer.
I agree, while you might have the power things like GVWR and especially the RAWR will most likely limit the actual trailer you can tow. As a WAG take the GVWR of the trailer and then calculate the max tongue wt. as 15% of that and then subtract 300 or 400 lbs of that that will go to the TT axles and the TV FA and add the rest to you fully loaded and fueled TV (i.e. all passengers and cargo in the TV) scaled TV wt. and if the rear axle is between 80 and 90% you should be in the ball park. If the trailer is a front kitchen I would want to keep that % closer to 80 than 90 just for a little more margin in this WAG estimate.
Larry
2001 standard box 7.3L E-350 PSD Van with 4.10 rear and 2007 Holiday Rambler Aluma-Lite 8306S Been RV'ing since 1974.
ALL TRAILER MODS>>ETERNABOND INSTALL>>RAINKAP INSTALL
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