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JJaxon
09-17-2020, 03:29 PM
2020 Ram 3500 DRW Laramie 4x4 LB weighs 8660 with me and a tank of fuel, no hitch, no passengers, no tools, just the truck as it was delivered to me. I will post the weigh tickets showing the stats. The hitched up ticket has the 5th wheel loaded but no liquids except 15 gallon of GAS for the generator, no perishable food, no motorcycle, but pretty much everything else that I camp with is in there, including clothes.
Truck:
GVWR is 14000 lbs.
GAWR Rear is 9750 lbs.
GAWR Front is 6000 lbs.

As shown in another thread my Payload sticker says NTE 5621lbs cargo and passengers.

Here is where I need the help of others, experts of the forum. Seeing these numbers, what is my pin weight?

This truck was built in August 2020.
Placard on door shows front tires at 80psi and rear at 65psi, am I wrong in thinking that is reversed? My last 2 Rams had the fronts at 65 and the rear at 80 (Single rear wheel axle) I ran 80 PSI most all the time all 4 tires w/o any issues.

Thanks in advance for the help!

wiredgeorge
09-17-2020, 03:33 PM
Would think the dually double rear tires might be taking up weight more than a single so 65 PSI sounds like about right; LRE on the front at 80 PSI. That is just conjecture and I will leave the numbers to those who don't use their fingers and toes to cypher numbers.

gearhead
09-17-2020, 05:07 PM
80 front and 65 back per my door sticker. That is what I run when loaded. If I'm not loaded up I drop the rears down to 44, maybe 42.
FYI...I tried all kinds of alternatives to the OEM plastic valve extenders for the inside duals. Nothing worked. I went back to the plastics. Got a couple from the dealer to keep in the console. What does work is a tire inflation air "gun" with a straight tip, not angled.

rjrelander
09-17-2020, 05:36 PM
Experts please correct these calculations.

pin = (steer2 + drive2) - total1 = (5020 + 7200) - 8660 = 3560

trailer = trailer2 + pin = 12360 + 3560 = 15920

[EDIT]

You can also do it this way …

trailer = total2 - total1 = 24580 - 8660 = 15920

pin = trailer - trailer2 = 15920 - 12360 = 3560

Same math depending on how you look at it. By the way, your mostly unloaded pin weight is the same as my trailer's dry weight. I could load my entire trailer on the back of your truck and it wouldn't even breathe hard. :-)

JJaxon
09-17-2020, 05:56 PM
Thank you Randi. I knew there was a formula but could convince myself what I remembered was right. I used a slightly different method but got the same result.
Thanks you.

JJaxon
09-17-2020, 05:58 PM
By the way, your mostly unloaded pin weight is the same as my trailer's dry weight. I could load my entire trailer on the back of your truck and it wouldn't even breathe hard. :-)[/QUOTE]

:cool:

rhagfo
09-18-2020, 06:53 AM
80 front and 65 back per my door sticker. That is what I run when loaded. If I'm not loaded up I drop the rears down to 44, maybe 42.
FYI...I tried all kinds of alternatives to the OEM plastic valve extenders for the inside duals. Nothing worked. I went back to the plastics. Got a couple from the dealer to keep in the console. What does work is a tire inflation air "gun" with a straight tip, not angled.

X2 to the inflation
You only need 65 psi in the rears as you have 4 tires, with a 9,750# rating if you took them to 80 psi then they would support nearly 12,000#, and ride like rocks. Just because a tire say 80 psi max on the sidewall you don't need to inflate to that for them to work for the load.

Javi
09-18-2020, 07:40 AM
My F350 with LT245/75R17E tires calls for 65 psi all the way around.. and that's what I run..

wiredgeorge
09-18-2020, 08:36 AM
My F350 with LT245/75R17E tires calls for 65 psi all the way around.. and that's what I run..


OK, You have teeny-tiny 17" tires on your F350... (have 18" 275 width on my old beater and they came stock from Ford).... anyway you have LRE tires. What does it say on the sidewalls? Thought all LRE tires said xxx lbs @ 80 PSI. I run my tires at 80 PSI all the time, even when not towing and they do ride like a rock... the way a truck is supposed to ride. On a serious note, I have seen that taller tires with the same load rating give a higher payload. Noticed this when looking at a truck magazine while waiting for an appointment. They talked about how companies achieved higher payloads and taller tires were one of the many things... Not sure how they got that but that is my recollection (I am getting old so memory isn't a strong point).

Javi
09-18-2020, 09:02 AM
OK, You have teeny-tiny 17" tires on your F350... (have 18" 275 width on my old beater and they came stock from Ford).... anyway you have LRE tires. What does it say on the sidewalls? Thought all LRE tires said xxx lbs @ 80 PSI. I run my tires at 80 PSI all the time, even when not towing and they do ride like a rock... the way a truck is supposed to ride. On a serious note, I have seen that taller tires with the same load rating give a higher payload. Noticed this when looking at a truck magazine while waiting for an appointment. They talked about how companies achieved higher payloads and taller tires were one of the many things... Not sure how they got that but that is my recollection (I am getting old so memory isn't a strong point).

OEM standard tire/wheel for a 2015 F350 DRW is 17"
https://media.ford.com/content/dam/fordmedia/North%20America/US/2015_Specs/2015_SuperDuty_Specs.pdf

As to the max inflation embossed on the tire... it is 80 PSI... and on my F250 which came with the same tire the sticker PSI was 65 front and 80 rear.. which is what I ran loaded.. un loaded I ran 65 in the rear also..

rhagfo
09-18-2020, 10:03 AM
My F350 with LT245/75R17E tires calls for 65 psi all the way around.. and that's what I run..

Likely because yours is only a 4x2 so you don’t have the weight of the front drive axle.

wiredgeorge
09-18-2020, 01:27 PM
Likely because yours is only a 4x2 so you don’t have the weight of the front drive axle.


The mysteries of life unfold when you have wise folks around you to point out things that ought to be obvious but are not obvious to the somewhat slower such as myself!

LewisB
09-18-2020, 04:22 PM
Likely because yours is only a 4x2 so you don’t have the weight of the front drive axle.

I think that's right. My 2017 F350 DRW is nearly identical to Javi's except it is a 4X4 (or would that be 4x6):lol: Same size tires as spec'd by Javi, but the pressures for my 4x4 are 70 Front and 65 Rear. So it seems like the heavier front axle does call for higher pressure.

29868

TYHLR
09-24-2020, 09:18 AM
I have used the chalk method for many years to determine proper inflation while loaded and unloaded with a great deal of success.


I inflated the tires as recommended by the tire manufacturer.


I then drew one chalk line across the complete tread all tires and drove the truck approx 100 feet. The wear marks on the chalk will tell you if the tires are either over or under inflated based on the wear of the chalk. You continue to do the chalk test when adding or removing air until the chalk line wears evenly across the entire tire tread. I did the same thing with the camper hooked up.


At the end of the day I run 70 in the front 65 in the rears unloaded. 90 PSI on all four corners with the camper hitched up.


P.S. I run 19.5 tires and wheels.


Hope this helps.