I have a weight question

[Stableduck]

I have an old (1984 Alpenlite) 5th wheel.
I was thinking I don’t have enough pin weight, I don’t have a cat scale near me but I did run it across a scale at a gravel pit. I calculated 610 pin weight. I have been putting my tool box and Honda gen over the pin to add weight
I have only made a few trips with it so far but it tows great! I’m towing with a 1500 ram so I’m trying to be careful about weights.
I found the original brochure for it and it’s saying gross axle weight 3860. And hitch weight 660. I’m guessing what they are calling gross axle weight is dry weight.
Then 660 would be about 17%
I’m attaching a pic of the brochure and tag on the trailer to help

[Old-Biscuit]

Per the trailer data plate
GVWR 6392#
FAWR 3196#........with 'P' tires which are passenger tires/32 psi

RAWR 3196#........with 'P' tires



Unlike todays trailers you have MORE axle capacity then trailers GVWR
The Gross axle weight 3860# is DRY weight and the 'hitch' weight 660# IS based on that dry weight
That does come out to 17% dry pin weight


You stated you figure you have 610# pin weight???
How do you have less pin weight then DRY??


Gravel pit scales are OK just have to do more figuring.
Total weight truck/trailer (GCVWR)

Then drop trailer and do truck alone (GVWR)



Won't give you individual axle weights but you can come up with what weight has been added to trucks weight (WET Pin) and what trailer weighs (Total truck/trailer MINUS truck)
Also subtract the added weight to truck from number you get from GCVWR-GVWR ---that would be trailer axle weights


Even if trailer is fully loaded to its GVWR your 1500 will do fine.

[Stableduck]

Originally Posted by Old-Biscuit

Per the trailer data plate
GVWR 6392#
FAWR 3196#........with 'P' tires which are passenger tires/32 psi

RAWR 3196#........with 'P' tires



Unlike todays trailers you have MORE axle capacity then trailers GVWR
The Gross axle weight 3860# is DRY weight and the 'hitch' weight 660# IS based on that dry weight
That does come out to 17% dry pin weight


You stated you figure you have 610# pin weight???
How do you have less pin weight then DRY??


Gravel pit scales are OK just have to do more figuring.
Total weight truck/trailer (GCVWR)

Then drop trailer and do truck alone (GVWR)



Won't give you individual axle weights but you can come up with what weight has been added to trucks weight (WET Pin) and what trailer weighs (Total truck/trailer MINUS truck)
Also subtract the added weight to truck from number you get from GCVWR-GVWR ---that would be trailer axle weights


Even if trailer is fully loaded to its GVWR your 1500 will do fine.

I don’t have the weights with me I’m at work.
I weighed the truck, then came back with the trailer. Weighed front axle as I drove on then whole truck with the wheels of trailer off the scale, then combined.
If I remember right the truck was 610 heavier connected with the trailer off the scale.
I think I had about a 1/2 tank of water which is behind the axle so it might have taken weight off the pin

[Stableduck]

I did upgrade to 8 ply tires

[Theunz]

I'm sure that the designers took the pin weight into consideration, so if it tows fine I wouldn't be concerned. Be careful not to load too much weight in the rear and you should be ok.

[ScoobyDoo]

Need some slight corrections,

Originally Posted by Old-Biscuit

Gravel pit scales are OK just have to do more figuring.
Total weight truck/trailer (GCVWR) GCVW

Then drop trailer and do truck alone (GVWR) GVW

The scale does not give you ratings, but actual weight, that must be compared to the rating

Originally Posted by Stableduck

I don’t have the weights with me I’m at work.
I weighed the truck, then came back with the trailer. Weighed front axle as I drove on then whole truck with the wheels of trailer off the scale, then combined.
If I remember right the truck was 610 heavier connected with the trailer off the scale.
I think I had about a 1/2 tank of water which is behind the axle so it might have taken weight off the pin

I have weighed many times on quarry scales, and have faith in them when they are doing what they are designed to do. They are to compare gross weight MT and loaded. Most quarries don't do it but if they are buying or selling more valuable stuff they will make the truck stop at the same point on the scale all the time. (Quarry I worked out of a lot, when buying the rock I would stop at one end of scale. Paid to haul, stop at other.)
Once we where having trouble with the arithmetic trying to get the axles right with a heavy machine. After about 4 tries, I read the scale with only steer, pulled all 8 on to get the gross, then dropped steering off. The 8-7 was 1800lbs less than what 1 was when read by itself. The Cat is a pain when long and wide, but at least I was sure of the numbers. BTW, when we got it all adjusted, the steering axle was a pinch over 16,000 lbs.
I think I understand how the loaded trailer pin weight could be less than advertised MT...