Possible CCC Upgrade

[Williebago]

Wondering what I am missing? It seems like it would be pretty simple and inexpensive. We recently moved up from a 2003 Dolphin on a W22 chassis with 22K GVWR and 26K GCWR to a 2019 Newmar on a F53 chassis with a 24K GVWR and 30K GCWR. Problem is with full water we dropped from 3,300 pounds of CCC to only 1,300 pounds of CCC. So that got me looking at the Ford specs for the F53 chassis and comparing everything between the 24K and the max 26K chassis that both have the same 30K GCWR.

And what I found was that the only apparent difference is the rear axle leaf springs. The 24K has 15,500 pound springs and the 26K has 17,500 pound rear springs. Same front axle and 9,000 pound springs. Same 17,500 pound Dana S17060S rear axle and differential. Same brakes and HydroMax specs and 15" rotors front and back. Same 50,000psi frame steel. Same everything except for rear leaf springs.

If I just change the leaf springs up to the 17,500 pound units I would be back up to the 3,300 pound CCC I have been used to. Since we occasionally travel to football games with "full occupancy" plus cargo we would be at the 3,000+ pound CCC.

So, what am I missing?

[MountainAir05]

You also might not be taking in on how much the two couch weight. A old one and the new one.

[Williebago]

"Might be smart to weigh your rig loaded the way you want to run it. If the front axle is over with that load, what do you gain dicking around with the back?"

My apologies JRscooby, I really need to learn how to do the "Quote function" on this board.

The reason for increasing the rear axle load is on an extended length gas coach, 37ft in my case, there is considerable rear overhang and I have a lot of behind the rear axle basement storage. If I load all of the tailgate stuff as far back as I can and put the 100 lb charcoal grill on the 2" receiver hitch it unloads the front axle due to the principle of lever and fulcrum. Does not change anything with regard to the maximum CCC I have to work with however. And based on the same physics it starts rapidly adding weight to the rear axle.

I am pretty conscious about weight, axle overloading, tire pressure and capacity, balance, etc. not only for safety, but handling as well. We use our coach a lot and in a wide variety of ways. Not really practical to weigh all the time so the goal is to know my best loading strategies and know I have plenty of left over capacity on each axle.

But, in doing some more research and analysis, I believe the best solution for me will be to add rear axle air bags and an on board compressor so I can adjust the pressure from the cockpit. I can use them to add the weight capacity if needed and also to jack up the rear end if I see a gas station or shopping mall driveway approach that looks iffy on dragging the tail. This would avoid the stiff spring when running unloaded and give me easy on demand flexibility. Since every other component is exactly the same I am pretty sure the chassis can handle the few times I need the other pounds of CCC.

[JRscooby]

Might be smart to weigh your rig loaded the way you want to run it. If the front axle is over with that load, what do you gain dicking around with the back?

[carringb]

Yes, just upgrade the springs. Or just add Sumos. No reason to over-think this. You've correctly identified the component driving the lower GVWR. The sticker only reflects the configuration as it left the factory, and is intended to inform YOU how it was configured. Nobody is going to weigh you, your insurance *probably* doesn't exclude changing springs (but check! Cheaper online policies exclude coverage if there are ANY suspension modifications), and the only thing illegal is if you tried to mis-represent the original GVWR at the time of resale.

[PastorCharlie]

674 divided by 8.3 equals 81.20481927710843 gallons.

Does that include full hot water tank plus water in lines?

My Newmar has a 75 gallon fresh water tank and 10 gallon hot water tank plus water in lines. That total 705.5 lbs. plus water in lines. I have the same chassis as you. Mine has 10 seat belts and sleeps 10. Only 2 use it.

[Alan_Hepburn]

So it looks like your new coach (the house part) is probably heavier than your old one. Things like the type of wood used in the cabinetry, the number of cabinets, the size of the slides, and a myriad of other things are eating up your carrying capacity. While there is nothing you can do about the ratings given by the chassis manufacturer you can certainly allow yourself some capacity by changing the springs, or adding a leaf or two. It won't change the rated capacity, however. You say the axles are the same rating, but make sure the wheels and tires are rated for the extra weight as well.

[Williebago]

Williebago,
Can you post a picture of the CCC sticker Newmar put in the unit? It would help us all understand better.

Bruce,
Have not gone thru the process to post a picture here, but here is what the label in the cabinet says:

"Cargo Carrying Capacity (CCC) Computation"
GVWR = 24,000 pounds
Minus UVW = 21,922 pounds
Minus Propane (25 gal.) = 105 pounds
CCC for this motorhome = 1,973 pounds
Combined weight of occupants and cargo should never exceed CCC.
A full load of water equals 674 pounds of cargo. (8.3 lb/gal)
Dealer installed equipment and towed vehicle tongue weight will reduce CCC

This is pretty much verbatim what the label says along with definitions of GVWR, GCWR, UVW, and CCC and the necessary liability warnings, etc.

[Walaby]

I don't think anything you do will change the stickers.

So, if the mods you propose doing make it more capable in your mind, then I say just do it.

Mike

[Bruce_Brown]

Williebago,
Can you post a picture of the CCC sticker Newmar put in the unit? It would help us all understand better.

Thank you.

[Dale_Traveling]

What are you missing? That Ford often makes mistakes, and posts a disclaimer for such, in the consumer literature and listed part numbers in addition to not publishing every technical detail and differences between chassis models so proceed at your own risk.

Newmar lists the approximate CCC for a 2019 Baystar 3626 at approximately 3426 lbs. Where did the 1974 number come from? 3426 gives you 489 lbs for each seat belt. Newmar also makes mistakes in thier literature but I would expect the CCC of a Baystar 3626 to be fairly close to 3400 lbs +/- a few percent of the weight.

[dougrainer]

I would send the request for modification to Newmar. They built the RV and they would be the best resource for a safe correct answer. Make sure you include the chassis VIN and the Newmar 6 digit unit number. Doug

[Williebago]

What is really going down here is that our old coach, the 35ft Dolphin, legitimately had about a full 2,000 lb. more CCC than our new 37ft Baystar. I weighed the Dolphin fully loaded several times and was really never close to its full CCC capacity whether we were loaded for a 10 week trip to Alaska or loaded with all the tailgating gear and planning on taking 7 full size adults to a football game.

With the new coach, I do have to be very careful on how it is loaded for each trip. As I said, the sticker says the 80 gallon water capacity is 664 lbs. and is to be subtracted from the CCC leaving only 1,300 pounds for occupants and other cargo.

Also, the frame section and steel strength is exactly the same. Everything is exactly the same on the spec sheets except for the capacity of the rear leaf springs. The raw curb weight of the stripped chassis is 7,381 lbs for the 24K frame and 7,394 lbs for the 26K frame with the same 252" wheelbase.

I know manufacturers constantly struggle with cost creep on every design they put forward to build and sell to the public and chassis manufacturers, in this case Ford, offers a pretty wide varied of chassis capacities and wheel base lengths to accommodate desires of their manufacturing customers, but if the difference in cost is for 13 more pounds of steel in the springs to get another ton of CCC, why not. But my original post is not to be critical of manufacturers about this CCC topic or to disregard the need for any one to not fully understand the loading of front and rear axles for any type of trip one is packing for. Those are both topics for another post.

I just want to know what am I missing in considering replacing the rear leaf springs?

[dodge_guy]

Do you really need 75 gallons of water for a football game?

I agree your math and numbers aren't making sense! I'm seeing a 3400lb CCC. Minus 673lbs, leaves you with 2700lbs for people and cargo. That's less, it not enough to worry about and certainly not enough to start changing springs.

[valhalla360]

Your numbers aren't making sense. Is the CCC 3300lb or 1974? (I looked up online and it shows 3400lb CCC)
Are you really taking 7 200lb people?

A couple thoughts:
- you mention the steel strength that they use in the frame but is the frame the exact same dimensions?
- It might just be the springs that are different and functionally, you can carry more weight but the sticker doesn't change. I can all but guarantee the manufacturer won't sign off on it no matter what the real situation is.