Scaled my duramax last night.

[Ryan03]

On the way home from my parents last night I was driving past a truck stop with Cat certified scales. At the last minute I decided to pull in and scale my truck with me in it{230lbs} to get the axle weights. I had been wanting to do this for some time so that I could plug these weights into the tire manufacturer inflation tables to see what I should be inflating the tires to. The truck is a 2003 2500HD regular cab 4x4, DMax/Allison, 265 75 16 tires, a diamond plate bed tool box loaded with an assortment of chains, tow straps, ratchet straps, and four or five hitch receivers. It has a Meyer Ez Classic mount plow system, which means the head gear, pump and hitch stay on the truck. Finally I have 700lbs of plow counter weight in the bed and 3/4s of a tank of fuel.

The weights were as follows

Front axle 4,240lbs

Rear axle 3,780lbs

Total 8020 !!!!

I was very surprised to see how heavy I was, considering i weighed in without the plow blade installed which I am figuring will add another 650lbs [meyer ST 90]. This will put the total weight to a whopping 8,670lbs. This is only 530lbs away from my 9200lb GVWR, and the plow blade will put me about 100lbs over my 4800lbfront axle rating. Im guessing my truck weighs around 6300lbs minus the plow stuff, me, and all my junk. It is really something how much weight those little odds and ends most of us carry with us in our trucks add up to.

For the record, I could not find a Cooper inflation table online, but Michelin and Bridgestones called for right around 50psi front and 40psi rear. I put the tires pressure at 45psi rear and 55psi front just to be safe.

 

[General Lee]

You running "E" rated tires?

 

[Ryan03]

Yes, they are E rated.

 

[Diamondpilot]

That is about right. My 05 Dmax 3500 srw 4x4 crew cab long bed was right at 7,000# with me and 2/3 tank of fuel.

Nothing else other than about a 50# tool kit and a tow Strap. Its GVWR was 9900#

In comparison my 04 F250 4x4 short bed diesel 4x4 was 7,500#. It has a 10,000# GVWR.


My 06 F350 4x4 srw diesel is 7,600# It has a 11,500# GVWR.


My 08 Nissan Titan 4x4 extened cab weighs 5,680#. Its GVWR is 7,000#.


Chris

 

[mrmikey]

Due to the leverage won't the actual weight on the front end be more than the weight of the plow?.....Mike

 

[crashz]

Ryan, what does the door sticker say for tire pressures? 55 and 45 psi seem low. My recommended pressures are 60 front and 70 rear. With nearly 2500 lbs per tire in the front, I think you need a bit more pressure. But I bet traction is pretty good.

 

[Morning Wood]

I would never run my tires that low. With the plow on I would be running them 70-80. About max. And I would be carrying more ballast and running those rears almost max as well

 

[schmism]

THe E rated tires i run on my E350 list 80 rear 50 front

If i was plowing with a pickup and i new i had that much weight on the front i would up the PSI on the tires to carry the weight.

I had my trailer and van at the gravel yard about 4 weeks ago. was 11,000 n change empty with trailer. figure my trailer is like 3500lbs empty or that puts my van at 7500+. I ended up picking up 4200lbs of gravel. (i asked the loader guy for 2 ton)

 

[megaboz]

Air pressure and proper wear on tires when unloaded is going to vary on tire manufacturer. I run Michelin ms2 and run 65 front and 62 rear to get proper wear.

I get fairly even wear at these pressures unloaded. Depending on the truck, air pressures could vary.

Of course this is what I run unloaded. Do what you need to be safe.

 

[Ryan03]

Ryan, what does the door sticker say for tire pressures? 55 and 45 psi seem low. My recommended pressures are 60 front and 70 rear. With nearly 2500 lbs per tire in the front, I think you need a bit more pressure. But I bet traction is pretty good.

My door sticker states 60 psi front and 80 psi rear. This is for the stock size 245/75R16 tires. I have long since upgraded to a 265/75R16 tire, which can carry a little more weight. I currently have Cooper Discoverer AT3 tires in the 265 size, load range E. The max load stated on the side of the tire is 3,416lbs at 80psi. single. The GAWR on the rear is 6,084 according to the tag in the door jamb, and the front is 4,800. I never really thought about it before, but it is a little strange that the front and rear GAWR add up to 10,884, which is considerably more than the 9200lb GVWR. I am thinking that the factory states the tire pressures assuming each axle is loaded to 100% of the GAWR for liability purposes, when in fact in the real world most of the time the GAW is much lighter calling for a lower pressure to obtain maximum wear and traction. Here is a Bridgestone inflation table, http://www.trucktires.com/bridgestone/us_eng/load/load_pdf/loadTables.pdf scroll about 1/4 of the way down the page to the 265/75R16 to view the inflation table. Here is a link to a Michelin light truck inflation table, which reads in per axle weight rather than individual tire weight. http://www.google.com/url?sa=t&rct=...eEIKR18VOKjxY5Hg&bvm=bv.1355325884,bs.1,d.dmQ

 

[Diamondpilot]

I don't think in any of the 15 or so trucks I have owned from Ford, Toyota, GM, Nissan, and Dodge have had the sum of the axle ratings equal the GVWR.

This gives flexibility in loading.

How does your 2500 do with a plow? Any major tire wear? Around here none of the dealers will sell a plow for them without a front end upgraded kit like Meyer offers. The 4,400# limit has been a factor. This has been a reason you see many more plows on stait front axle trucks with higher axle ratings.

Chris

 

[Ryan03]

I don't think in any of the 15 or so trucks I have owned from Ford, Toyota, GM, Nissan, and Dodge have had the sum of the axle ratings equal the GVWR.

This gives flexibility in loading.

How does your 2500 do with a plow? Any major tire wear? Around here none of the dealers will sell a plow for them without a front end upgraded kit like Meyer offers. The 4,400# limit has been a factor. This has been a reason you see many more plows on stait front axle trucks with higher axle ratings.

Chris

That makes sense about the GAW ratings. I have yet to actualy plow any snow yet with my DMax. I installed the plow this fall, but it has not snowed enough to accumulate here yet. Im not complaining though !!!! I have hooked the plow up and driven down the road, and it did fine, The front sagged 1/2 to 3/4 of an inch when i raised the plow, but the back came up 2 inches. 700 lbs in the bed seems to stop all of the back end rise when lifting the plow. We have a few reg cab 2500HD trucks at work with plows, a 2005 and 2 2006s Two have western straight blade ultra mounts, and the other has a Meyer EZ classic 8ft poly professional straight blade. My truck as well as the DOT units all have the GL torsion bars from the factory which yields a 4800 lb front GAWR. All trucks have had the T bars turned up to level, and the work trucks sag a little over an inch with the bigger plows on them. We have had really good luck with our 2500HD s mechanicaly We normaly get well over 100k before the first front end over haul, tire wear has not been an issue, and they plow great. These trucks are used by supervisors during winter road snow removal operations, so they are not getting crashed into snow piles in parking lots constantly, they are plowing freeway turn arounds, Our outpost and head quarters, cleaning up intersections, freeway ramp tails and burms etc. They will drop the plow and go for 12 hrs, literaly. The biggest issue We have had with the 2500 s is rust in the rocker panels, cab corners, hood, and brake and fuel lines. The Magnesium transfer cases also corrode away badly around all the case bolts till all the oil leaks out. All 3 work trucks have had t cases replaced due to corrosion, min is still nice, but I give it special attention since I know it to be a problem area.

 

[Peacock]

Trucks never have GAWR close to the true capacity of the axle. The AAM axle in that DMax truck has a true rear axle capacity of 10k or so.

 

[mikehaugen]

Trucks never have GAWR close to the true capacity of the axle. The AAM axle in that DMax truck has a true rear axle capacity of 10k or so.

are they still using the "14 bolt" rearend? I once had a '76 gmc with 8600 gvwr that had a 14 bolt rear end and a dana 44 up front- seemed like an odd combination :confused3:

 

[Peacock]

Yes. It's made by AAM now. Same basic rear axle. His truck has the 11.5" rear axle. The 14 bolt semi floater is 9.5" and the full floater is 10.5".

 

[crashz]

The old 14 bolt FF is in the gas HD trucks and has been since the re-design in 2000.

Thanks for links Ryan. Typically I've run my tires to the max pressure in order to get the best gas mileage and for load carrying. But its not the best for tire life.

 

[Peacock]

The old 14 bolt FF is in the gas HD trucks and has been since the re-design in 2000.

Thanks for links Ryan. Typically I've run my tires to the max pressure in order to get the best gas mileage and for load carrying. But its not the best for tire life.

It's been revised a bit. I believe the carrier is a different design. AAM produces it now for GM.

 

[Ryan03]

The old 14 bolt FF is in the gas HD trucks and has been since the re-design in 2000.

Thanks for links Ryan. Typically I've run my tires to the max pressure in order to get the best gas mileage and for load carrying. But its not the best for tire life.

I have seen lots of 2500HD's with a AAM full floaters and gas engines. Usualy the gassers dont have a harmonic balancer on the pinion where the AAM in the diesels always seem to.