The dreaded GVWR question

[railbuff]

We weighed our truck this last weekend, with the following results.


Conditions: Driver + Passenger + full fuel tank + hitch

Truck Weights (from label on truck)


(1) GAWR (Front) = 4670 lb
(2) GAWR (Rear) = 6084 lb
(3) GVWR = 9200 lb


Actual Weights of Truck (CAT Scale at 10 acre. 2003/07/27
(4) Front axle = 4320 lb
(5) Rear axle = 3120 lb
(6) Gross weight = 7440 lb

Maximum Truck Capacities (

[wheeler]

Yes I think you've got the math right; the salient point being GVWR is extremely limiting (versus the rear axle weight rating) in terms of your permissable hitch pin weight.

Not sure about Titanium, but I believe the manufacturers' posted pin weight numbers are with the units ready to roll but not loaded (your stuff, holding tanks, etc., etc.) Roughly, I've heard 5er pin weights should be about 25% of the whole trailer weight. One suggestion: "weight creeps up:" I don't think I've ever heard of someone whose low pin weight pleasantly surprised them. I think factory estimates are low-- mine was.

That much said, I tow a trailer heavier than yours with an '03 2500HD D/A. About six months ago I decided to change the tires from stock 245's to 265's to gain another several hundred pounds of load capacity (in my case tire change required wheel change as well, from 6.5" to 8" wheels, not cheap). Interestingly, it sounds like GM is offering a SRW "1 ton" truck in '04-- and, unless there are other mod's I don't know about, it is exactly what I have. There is the black and white of numbers and then there is common sense-- but one thing's certain, the GVWR your truck was "born with" on that label from GM is the GVWR that it stays with, despite any additions or improvements you might make.

Many people tow at and beyond the weights you are proposing-- but what is your comfort level? Good luck. --wheeler
(RV Webpage: http://homepage.mac.com/gadgetnut/PhotoAlbum3.html

[roegs]

You've just described why many who tow a 5th wheel go with a 3500. With many pin weights, you run out of GVWR too soon. You may also need to watch the front axle weight...there is not much to work with.

Wheeler has a good point about watching the max weights. You're doing the right thing checking with a scale. If worse came to worse, and you were involved in a serious accident while towing, your insurance may not need to pay if you have exceeded the mfg ratings.

[AbqGeorge]

Yep railbuff, you've got it right!

My how those weights creep up!
Here's mine (all CAT scales):

Truck same as yours (? Ext Cab) with:

Reese 16k slider, Rhino liner, Westin Running Boards (tubes), full tank of diesel and NO driver or passengers:

(1) Front 3920
(2) Rear 2840
(3) Total 6760

With my 27' Aluminum superstructure/aluminum siding Sunnybrook with full fresh water, wife, dog, Honda EU3000 Generator sitting in the bed:

(4) Front 4160
(5) Rear 5000
(6) Trailer Axle 6720
(7) GCW, a measley 15,880

So, (4)+(5) = 9160, but wait (or should I say "weight" smile.gif ) my 225# butt wasn't in the truck :(

So, (5)-(2)-165# for the Honda and the pin weight on my little 8000# FW = 1995# !! (yeh, I know, some of the dog and wife are in here, but they ain't that big!)

So, if I leave the generator at home (dog and/or wife is probably out of the question smile.gif ) and don't fill the fresh water tanks I can keep 'er totally legit so to speak.

I think when you decide to upgrade to that 32' Titanium a dually may need to be in your planning? This is exactly the reason GM is bumping a rebadged (from 2500HD to 3500 SRW) to 9900#. My understanding is the only change will be 265 tires and a different spring pack?

Go over to RV.NET and I'll bet you can find some pretty accurate weights for the Titanium.

See ya down the road,
Geo.

Oooops, and on edit.... this was BEFORE I added the 45 gallon Transfer Flow. Oh, oh!

[DMAX Daddy]

I would think you could put some of the "movable" weight behind the trailer axle to lighten the hitch a little? I guess that depends on the type of trailer and what your load is.

[DmaxMaverick]

You configure your weight with either GVWR or GCWR. Not both.

If you only have the truck loaded (cargo, camper, etc.), with no trailer, then the GVWR applies.

If you have a trailer attached, then the GCWR applies and only GAWR applies, as long as you are under GCWR. The truck can be over GVWR as long as axles aren't exceeded. The trailer also has to be in compliance (weight distribution, brakes, etc.) for it's GVWR. Trailer GVWR is static and there is no GCWR for trailers.

This is why the numbers don't add up.

Also (uh-oh....more fuzzy logic), adding weight behind the trailer axle is a bad idea for the purpose of reducing pin weight. The formula for this is about 2:1 for most trailer configurations. Pin to axle and axle to bumper distances change the ratio, but not much. 50#'s off the pin will require about 100#'s of weight at the trailer bumper. Adding 100#'s to the trailer bumber would increase the trailer axle weight by about 200#'s. These numbers are not exact and vary with each setup, but it is close to the reality. It wouldn't take much to overload the trailer axle. The closer to the trailer axle you are adding weight, the greater the ratio. You can test this theory with a couple two-by-fours and some rocks.

Hope this doesn't confuse you even further. Cheers

[sonofagun]

railbuff,

Most trailers brochures do not include added factory options in their pin weight. The trailer is, usually, weighed before it is shipped and you can do some extrapolating from the advertised weight versus kin pin (%) and what your king pin might actually weigh. watch out for heavy upfront options like A/c and front slides, generators,etc. All that weight goes on the pin. You can get beyond the truck rating much faster than you realize. I listened for months to those on the forum who pull a heavy load with the 2500HD, like I was doing. I finally decided in the interests of 1. family safety, 2. insurance issues 3. wanting to carry a lot of stuff I couldn't 4. wanting to keep my bed mounted fuel tank filled since the generous 26 gal. factory goes so far, etc. to go to a 3500 now on order.

Good luck in your quest,
Bob

[DMAX Daddy]

Maverick,

Thanks for the explanation!

[chevmeister]

Originally posted by DmaxMaverick:
You configure your weight with either GVWR or GCWR. Not both.


If you have a trailer attached, then the GCWR applies and only GAWR applies, as long as you are under GCWR. The truck can be over GVWR as long as axles aren't exceeded. The trailer also has to be in compliance (weight distribution, brakes, etc.) for it's GVWR.

Thats true if you have a combination tag. but not unless it says 22,000 on the reg card. you can be 19000 total with 4500 on the front, 6000 on the rear and 8500 on a 10000 gvw trailer but your truck gvw is 900 over. ive been there before with a 71000# rig.

[ 07-29-2003, 05:57 PM: Message edited by: chevmeister ]

[roegs]

If you only have the truck loaded (cargo, camper, etc.), with no trailer, then the GVWR applies.

If you have a trailer attached, then the GCWR applies and only GAWR applies, as long as you are under GCWR. The truck can be over GVWR as long as axles aren't exceeded. The trailer also has to be in compliance (weight distribution, brakes, etc.) for it's GVWR. Trailer GVWR is static and there is no GCWR for trailers.
Maverick...I'd be interested in knowing where you obtained the info that GVWR can be exceeded when towing. My '03 manual specifically (page 4-79) states that GWV is to not be exceeded including weight of trailer tongue. There are a number of factors for GVWR...its not just based on axle capacity. The way I understand GVWR is its the max load for the truck, towing or not.

[AbqGeorge]

Before folks get led too far astray I suggest they read this carefully:

Chevy Trailering Spec (http://www.chevrolet.com/silverado/library/fs/index_trailering.htm)

Scroll to the bottom and you'll find this:

"RGAWR and GVWR: Addition of trailer hitch weight cannot cause vehicle weights to exceed Rear Gross Axle Weight Rating (RGAWR) or Gross Vehicle Weight Rating (GVWR). These ratings can be found on the certification label located on the driver door or door frame."

[moondoggie]

Good Day!

Take a look at Trailer Life mag. Boring mag, but this type of issue is their bread & butter. My mom & dad are snow birds in TX each winter, he gives me his old issues.

Blessings!

Brian Johnson, #5044

'82 6.2 1500 4X4 1/2T pickup, 4spd man w/ OD, bone stock, 335K+, "In Rust We Trust"
'89 6.2 4X4 1/2T pickup, bone stock, 145K+
'95 6.5TD 2500 4X4 heavy 3/4T pickup, Gear Vendors Aux. OD, 180K +
'95 6.5TD 1500 4X4 3/4T Suburban, Kennedy exhaust, 200K +