Air Bags for Duramax??

[Sparksy27]

I have a 2004 Chevy Duramax 2500. I will be purchasing a Stealth ck3012 fifth wheel in the near future. Do i need to get air bags for my truck to help level it out? I have heard that i dont need them with a smaller fifth wheel but i have also heard that they make for a much smoother ride. Any input is greatly appreciated. Thanks

[Dave_Monica]

Any idea what the pin weight loaded will be?

Dave

[Sparksy27]

Here is some information I pulled from their website. Let me know if you need anything else in order to help me out.

Dry hitch weight- 2,118
GVWR- 12,278
Cargo Carrying capacity- 4,400
Unloaded vehicle weight- 7,819


I am brand new to fifth wheels so I hope this is the information you needed. Thanks a ton

[milzat]

Yes, air bags.

[Herk7769]

Originally Posted by Sparksy27

Here is some information I pulled from their website. Let me know if you need anything else in order to help me out.

Dry hitch weight- 2,118
GVWR- 12,278
Cargo Carrying capacity- 4,400
Unloaded vehicle weight- 7,819


I am brand new to fifth wheels so I hope this is the information you needed. Thanks a ton

Yikes, is that dry hitch weight right?

That is 1 ton of pin weight not counting the weight of the hitch that you are putting on the 3/4 ton pickup. That is also the UNLOADED pinweight. Once you put 4400 pounds of personal stuff on board you will be pushing a ton and a half of pin weight.

I think you need to rethink that camper.

My 2008 GMC Sierra with Duramax and Allison Tranny is maxed out at 9,200 pounds Gross Truck weight. With the diesel engine weight, my truck is 7700 pounds rigged for travel (full fuel, hitch, generator, and family - and no we are not fat!). That only leaves 1500 pounds MAX PIN LOAD. ( I am running about 1150 pounds). I do have a little trouble since with the camper on, my front axle load is pretty close to the 4500 pound maximum. (about 4250 pounds)

Air bags do nothing to increase GVW. That is all front and rear springs, axle, and brake drum/rotor size so that you can carry and stop that beast.

Just because the "book" says you can pull over 15,000 pounds does not mean that you can carry the front of the trailer in your truck bed.

The 1 ton (single AND dual) has the same 15,000 pound rating as the 3/4 ton pickup. Have you ever wondered why? The tow rating is based on drive train. The max load carrying capacity is based on suspension.

[Sparksy27]

First off, thanks a ton for your rapid responses.

I was under the impression that the Stealth CK3012 was a smaller fifth wheel in which my 2500 Duramax would have no issues pulling. I have been told by numerous sales people that it is all about the GVW when determining if i could pull it. I believe my Duramax is rated for 15,500. I had no idea i needed to factor in suspension, axles, and everything else.

So basically, you would find it unsafe to pull a load like this?

Thanks again for your help

[Dave_Monica]

Your truck probably has a GVWR of 9200 lbs and a rear axle weight rating (RAWR) of 6100 lbs (label should be on the driver's door). As herk7769 has said, your truck loaded ready to camp will probably exceed 7200 lbs depending on the # of passengers, leaving less than 2000 lbs available for the hitch and the trailer pin weight. That would be to not exceed the GVWR of the truck. A lot of people would say that you're okay exceeding the truck's GVWR as long as you don't exceed the truck's RAWR of 6100 lbs. Go weight the truck (front and rear axles) loaded, ready to camp. You'll probably find that the rear axle weight is around 3200 lbs leaving 2900 lbs available for the hitch and pin weight before you reach the RAWR.

What is the weight limit you can put in the garage? As it's mostly behind the camper's axles, it will also reduce the pin weight. I would guess that with a couple of quads, you’d have a loaded pin weight of less than 2500 lbs. Reading a thread called real weights on RV.net you’ll see lots of ¾ ton diesels towing 12,500 lb 5er’s with a 2500 lb pin.

Dave

[Herk7769]

Originally Posted by Sparksy27

I was under the impression that the Stealth CK3012 was a smaller fifth wheel in which my 2500 Duramax would have no issues pulling. I have been told by numerous sales people that it is all about the GVW when determining if i could pull it. I believe my Duramax is rated for 15,500. I had no idea i needed to factor in suspension, axles, and everything else.

So basically, you would find it unsafe to pull a load like this?

Thanks again for your help

Dave has a valid point about the toys moving that weight aft.

How FAR it moves will depend on how much stuff you pack in the basement storage area. The camper is like a giant teeter totter. Light kid on one side at the end of the board, can balance a heavy kid close to the pivot.

Aircrews work with this all the time. Center of gravity too far aft, the nose pitches up and you crash. Too far forward; nose too heavy; not enough elevator authority to fly; you die. Too close to the center of lift; aircraft unstable and you need a computer to work the flight controls. Computer fails; you die. Center of Gravity just forward of the center of lift and the elevator works just fine and life is good.

Another tidbit. You NEED between 15% and 25% of the camper weight ON THE PIN to keep the camper stable on the road. At your max trailer weight of 12,500 pounds, the absolute MINIMUM pin weight you must have is 1875 pounds not counting hitch in the bed of your truck. At 20% (Optimum) that pin weight rises to 2500 pounds. At 25%, the maximum pin weight you get 3125 pounds (WAY over your TV's rating).

Below the minimum pin weight the camper wants to wag your truck and you will find yourself sawing the crap out of the steering wheel to steer a straight course. Since I run about 18% myself to keep the gross Vehicle weight below 9200 pounds, my front tires wear A LOT faster than my rears. I accept that because I have no choice. I am running my TV close to 9100 pounds now. Yes, I technically still have slightly over a 1000 pounds left on my rear axle, that would put my TV over 10,000 GVW.

Remember that the salesman's job is to sell you the biggest rig possible for the most money possible. (They lie.)

http://changingears.com/rv-sec-calc-...eight-fw.shtml

I found it! Use this calculator to determine the maximum safe camper for your tow vehicle. Good luck Sparksy

This is also cool for adjusting the calculated weight above.
http://changingears.com/rv-sec-calc-adjust-gvw.shtml

[Sparksy27]

Thank you so much for all of your help. I am going to use the calculator Herk provided me with to get a better idea of what my truck can handle. I was completely sold on my Stealth CK3012 and now have no idea what to do.

I guess I still have a lot to figure out before I can make an educated decision. Thanks everyone for your help and I'm sure there will be more questions in the near future! I am brand new so bear with me, a lot of your advice (terms) are rather unfamiliar but i am doing my best to learn as much as possible from all of you.

Thanks again!

[Herk7769]

Originally Posted by Sparksy27

Thank you so much for all of your help. I am going to use the calculator Herk provided me with to get a better idea of what my truck can handle. I was completely sold on my Stealth CK3012 and now have no idea what to do.

I guess I still have a lot to figure out before I can make an educated decision. Thanks everyone for your help and I'm sure there will be more questions in the near future! I am brand new so bear with me, a lot of your advice (terms) are rather unfamiliar but i am doing my best to learn as much as possible from all of you.

Thanks again!

Sparksy believe me when I say "There but for the grace of god!"

I was looking at a Montana! 14,500 pounds and the dealer ASSURED me it would all be fine on my 2500HD with the Duramax. (Butt Munch).

When I spotted the floor plan of the MUCH smaller 8526 Flagstaff I loved it.
I figured towing the 9,100 pound trailer would be a BREEZE with my "monster truck."

Wow was I ever wrong. I STILL had to watch tranny temps pulling in the Rocky Mountains.

Loading has to be carefully planned and I weigh at our local CAT scale before EVERY trip. My 2500HD is pretty much maxed out GVW wise almost every time we go (especially when we for to the Keys).

Without getting a 1 ton or better, leave the big campers to the duallies. You will be MUCH happier.

I am just SO happy I got the lighter camper. Yea, there are things about the Ultralite I hate (crappy lightweight frame and bumper for one) but after special ordering and modifying my TV I would have hated to sell it and buy a bigger one much more.

[Sparksy27]

This is probably a dumb question but....

How do you weigh the front and rear axles of a truck????

[MtnGuy]

A CAT scale should be able to do that in 1 pass.

For the local quarry scale, weigh the truck front axle, total, and rear axle without the trailer hooked up.

Go back to the scales with your trailer hooked up without changing anything in your truck. Now weigh the front axle of the truck by its self (front axle only on the scales) , the total truck with both axles on the scales without the trailer, with everything on the scales, and then just the trailer tires on the scales. The total of everything minus the initial truck weigh-in is the weight of the trailer alone. Subtract the truck alone weigh-in from the 2nd weigh-in from the truck only on the scales, and that will give you the hitch weight.......or take the total trailer calculated weight (total of all 2nd weigh in axles minus the truck) minus the trailer only axle weight.....that should also equal the hitch weight. The front axle weight with the trailer hooked up is easy....you already have that when the front axle only was on the scales. But you need to calculate to get the rear truck weight with the trailer hooked up. Take the total 2nd weights of the truck and subtract the 2nd weigh-in of the truck front axle.....that should be the rear axle weight. You can also take the total of everything 2nd weigh-in, minus the trailer axles and front axle of the truck, and come up with the same figure.

Are you confused yet ?? I think I am.

[Herk7769]

Originally Posted by Sparksy27

This is probably a dumb question but....

How do you weigh the front and rear axles of a truck????

Load the truck with everything you plan on camping with FULL gas; kids; wife; dog; and anything going in the bed including the hitch if you have one. Otherwise add 250 pounds to the rear axle number.

Go to the closest CAT Scale CAT Scale

Pay the 9 dollars.

Drive onto the scale with the front axle on the forward most plate and the rear axle on the second plate.

The operator will give you a print out showing your front axle weight; your rear axle weight and your GVW loaded.

Then you can use the calculator to see where you are. Subtract the GVW that you get from 9200 pounds and that is your maximum safe pin weight.

[Herk7769]

Sample work up from my last trip:

FIRST WEIGHT CHECK:

2008 GMC Sierra 2500HD Duramax crew cab SB Full tank with Pull-rite slider; Yamaha 3000SEiB Generator, 10 gallons diesel in cans; 2.5 gallons gasoline; 20 lb propane tank; wife; dog; milk crate wood levelers. ONLY

Steer Axle 4240 pounds ---> max 4500
Drive Axle 3620 pounds ---> max 6084 (based on springs)
GVW 7860 pounds ---> max 9200 pounds

SECOND WEIGHT CHECK with camper

Steer Axle 4360 pounds ---> max 4500
Drive Axle 4960 pounds ---> max 6084
(NOTE: OVERLOADED TRUCK 120 pounds) GVW 9320
Camper Axles 7680 ---> max allowed 8000 based on axles and tires

Calculated pin weight: 9320 - 7860 = 1460 pounds
Calculated Combined weight: 17,000 pounds ---> max 25,000 pounds
Calculated Camper weight: 7680 + pin weight 1460 = 9140 pounds
MAX camper weight 9120 pounds.

Where the pin weight falls:

(1460 pin weight / 9140 camper) * 100 = 15.94%
Safe Range 15% (1371 pounds) to 25% (2285 pounds)
Optimum pin to camper 20% = 1828 pounds
Adding another 400 pounds to my rear axle to get it to 20% would put me over my max gross weight for the truck by 620 pounds.

I could accomplish this by moving stuff currently stored in the dinette (my wine, beer, and soda supplies mostly) and putting them in the bathroom or bedroom. But WTH.

So why are Lou's front tires wearing out faster than the rears.
There ya go.

Easy as pie.

PS if you re-weigh within 24 hours it only costs a buck. So go weight the truck for 9 bucks; go home and hook up; go right back and reweigh for a dollar.

[MtnGuy]

Lou, shouldn't your hitch weight be the additional weight on the rear and front truck tires.....1460 lbs.??? That should give you a 16% hitch weight.

[Herk7769]

Originally Posted by mtnguy

Lou, shouldn't your hitch weight be the additional weight on the rear and front truck tires.....1460 lbs. ??? That should give you a 16% hitch weight.

Whoops you are correct. I missed that when typing it up.
It is the Delta of both axles.
Lou