Attempting To Calculate "Real World" max total loaded weight for my Georgetown

[CA Fisherman]

I am confused (not that rare a condition for me) trying to figure out the maximum load my motorhome 2014 Georgetown XL 334QS can handle. Ratings are as follows
GVWR 24,000 lbs.
GCWR 30,000 lbs.
GAWR Front 9,000 lbs.
GAWR Rear 15,500 lbs.

Tires are Michelin XRV 255/80R22.5 LR=G, currently inflated to 100 psi
Appears to me the maximum weight for single tire (@110 psi) is 2,360 lbs., and the maximum weight for tire (@110 psi) in dual configuration is 2,180 lbs.

If the above weight ratings are correct it would seem:
Maximum usable load for the front axle is 4,720 lbs., not the rated 9,000
Maximum usable load for rear axle is 8,720 lbs., not the rated 15,500
This then equates to usable GVWR of 13,440 lbs., not the rated 24,000

Hopefully I am somehow calculating incorrectly. Any comments, input, clarification, suggestions, will be most welcome.

[MR.M]

Originally Posted by CA Fisherman

I am confused (not that rare a condition for me) trying to figure out the maximum load my motorhome 2014 Georgetown XL 334QS can handle. Ratings are as follows
GVWR 24,000 lbs.
GCWR 30,000 lbs.
GAWR Front 9,000 lbs.
GAWR Rear 15,500 lbs.

Tires are Michelin XRV 255/80R22.5 LR=G, currently inflated to 100 psi
Appears to me the maximum weight for single tire (@110 psi) is 2,360 lbs., and the maximum weight for tire (@110 psi) in dual configuration is 2,180 lbs.

If the above weight ratings are correct it would seem:
Maximum usable load for the front axle is 4,720 lbs., not the rated 9,000
Maximum usable load for rear axle is 8,720 lbs., not the rated 15,500
This then equates to usable GVWR of 13,440 lbs., not the rated 24,000

Hopefully I am somehow calculating incorrectly. Any comments, input, clarification, suggestions, will be most welcome.

If you have G load rated tires it should be closer to 4400 lbs at 110psi


2360 is closer to an e rated tire

[CA Fisherman]

Mr. M. You sir are correct. Your response prompted me to take a second look at the tire sidewalls. It is embarrassing to admit that I had recorded the kg not lb weight rating. The ratings I should have used are 5,206 lbs. for single tire and 4806 lbs. for tires in a dual configuration. This equates to revised tire based front axle load of 10,412 lbs. and real axle load of 19,220 lbs. Now I will play a bit with load ratings at a lower psi (100) to see if I can help soften the ride. Again, thank you for taking the time to respond and for your eagle eyes!

[MR.M]

No problem , glad i got one right lol

[TitanMike]

Tire ratings are always the controlling factor regardless of the axle weigh rating. Ideally you'd always have a higher rated axle than the rating of the tires.

This would keep axles from bending when going over bumps. Better to sacrifice a tire than bend an axle.

Then just keep load beneath tire rating.


Remember the saying: "Why is it that people take up RV'ing to get away from it all then try to take it all with them"?

[dahagen]

In a couple of places on your RV you should find a yellow label listing weight info, including CCCC.

[CA Fisherman]

So far I have found GCWR, GVWR and GAWR for each axle. My weight distribution is not too bad, however I am going to try and move about 1,000 lbs. of load from the rear axle towards the front of the motorhome, for improved weight distribution and possibly lower tire pressures to improve ride.
I have individual scale weights for each tire position so have data to work with.

[weatherguru1]

For CAFisherman, I read your post on Weight distributions. I have a 2015 Georgetown 352XL with 4 slides also. Two questions come to mind. Are you having trouble with driving as to your weight distribution? Did you try the CHF on your unit. Mine drove me nuts driving before doing the CHF. (Cheap Handling Fix). I truly never felt any difference driving with regard to different tire pressures. (95 thru 105).

[CA Fisherman]

Originally Posted by weatherguru1

For CAFisherman, I read your post on Weight distributions. I have a 2015 Georgetown 352XL with 4 slides also. Two questions come to mind. Are you having trouble with driving as to your weight distribution? Did you try the CHF on your unit. Mine drove me nuts driving before doing the CHF. (Cheap Handling Fix). I truly never felt any difference driving with regard to different tire pressures. (95 thru 105).

Yes, I performed the CHF early on, then added a steering stabilizer. Recently I added SUMO's on the front axle resulting in a noticeable improvement. Knowing our MH is heavier in the rear and lighter in the front than I would like I added SUMO's to the rear axle. Now over all handling is much improved including wind sway from passing semi's and lane position stability. The negative of the SUMO's was a harder ride in the vicinity of the rear axle. I slightly dropped the air pressure on the rear axle dual tires and the ride improved. Now I am working to determine the most appropriate pressure for tires at all four positions.

[cariboo camper]

Originally Posted by CA Fisherman

I am confused (not that rare a condition for me) trying to figure out the maximum load my motorhome 2014 Georgetown XL 334QS can handle. Ratings are as follows
GVWR 24,000 lbs.
GCWR 30,000 lbs.
GAWR Front 9,000 lbs.
GAWR Rear 15,500 lbs.

Tires are Michelin XRV 255/80R22.5 LR=G, currently inflated to 100 psi
Appears to me the maximum weight for single tire (@110 psi) is 2,360 lbs., and the maximum weight for tire (@110 psi) in dual configuration is 2,180 lbs.

If the above weight ratings are correct it would seem:
Maximum usable load for the front axle is 4,720 lbs., not the rated 9,000
Maximum usable load for rear axle is 8,720 lbs., not the rated 15,500
This then equates to usable GVWR of 13,440 lbs., not the rated 24,000

Hopefully I am somehow calculating incorrectly. Any comments, input, clarification, suggestions, will be most welcome.

110lbs seems fairly high. Have you got a sticker somewhere in the unit that tells you what to inflate tires to? 110 lbs is probably the tire rating for max load for the tire. You may not even be near max for the tire rating as you are restricted to the GAWR. I would suggest 110 PSI would be for a much larger vehicle ie: higher axle ratings, larger spring packs such as in small semi trailer, large delivery truck. My motorhome states 82 PSI for 19.5 tires but the tire rating is much higher. See you got the KGs and LBs figured out.

[cariboo camper]

Originally Posted by TitanMike

Tire ratings are always the controlling factor regardless of the axle weigh rating. Ideally you'd always have a higher rated axle than the rating of the tires.

This would keep axles from bending when going over bumps. Better to sacrifice a tire than bend an axle.

Then just keep load beneath tire rating.


Remember the saying: "Why is it that people take up RV'ing to get away from it all then try to take it all with them"?

Not agreeing with that logic
Keep the load on or below the GAWR. If you had a higher rated axle than the tires and loaded the axle to max rating your tires would be jeopardized. Tires are always rated higher than GAWR. But your right, regardless, always keep load beneath tire rating. Load higher than GAWR or GVWR and you could be in trouble if scaled by police or DOT.

[CA Fisherman]

I am nearing the culmination of my project to set up the proper tire air pressure for my motorhome. I have attached two pdf files. One listing the single and dual tire load ratings at various psi’s along with the published motorhome capacity ratings as per the stickers on my MH. The other page lists the actual weights obtained at a certified scale. This page also includes a diagram showing various capacities along with actual weights and the individual tire air pressures I plan to adopt, factoring in a slightly higher psi then indicated by the Michelin chart. I continue to work to reduce the total weight on the rear axle along with shifting weight to the front axle. This is difficult to do since the residential refrigerator, water heater and washer/dryer are on the passenger side near the rear axle and the propane tank takes up the entire first storage locker on the left front. The motorhome weights are pretty close to when we go camping. The motorhome serves as our earthquake refuge, The fuel take is kept full along with the propane and 1/2 tank of fresh water which I drain and refill with soft water once a month. The refrigerator is always on and pretty well stocked, along with dry goods and clothes. I would welcome any comments/suggestions. Thank you!

[cariboo camper]

Originally Posted by CA Fisherman

I am nearing the culmination of my project to set up the proper tire air pressure for my motorhome. I have attached two pdf files. One listing the single and dual tire load ratings at various psi’s along with the published motorhome capacity ratings as per the stickers on my MH. The other page lists the actual weights obtained at a certified scale. This page also includes a diagram showing various capacities along with actual weights and the individual tire air pressures I plan to adopt, factoring in a slightly higher psi then indicated by the Michelin chart. I continue to work to reduce the total weight on the rear axle along with shifting weight to the front axle. This is difficult to do since the residential refrigerator, water heater and washer/dryer are on the passenger side near the rear axle and the propane tank takes up the entire first storage locker on the left front. The motorhome weights are pretty close to when we go camping. The motorhome serves as our earthquake refuge, The fuel take is kept full along with the propane and 1/2 tank of fresh water which I drain and refill with soft water once a month. The refrigerator is always on and pretty well stocked, along with dry goods and clothes. I would welcome any comments/suggestions. Thank you!

Good research. I to looked up charts for tire pressures etc.. Weighed motorhome loaded with what we normally carry and was below GVAW so I will adjust tire pressure as per calculations. Actually a little below the PSI on motorhome sticker.

Interesting that I recently purchased a winter tread for our snowbird trip down through Wash, Oregon, Idaho, Nevada, Arizona. When I picked up rig the tires were at 100 PSI, tire shop says they are a truck tire, the sidewall max pressure says 110 max so they filled them right up. Not good!

Everyone should be very diligent regarding tire pressure. Thanks for you post.