Are the axles on a 5er limiting issue of the posted manufacter max weight? Can you raise the limits by changing axles? (eg. 7000lbs to 8000lbs) The brakes could also be a problem.
Scott
Workinrvers said
03:37 PM Jun 4, 2012
not just axles but also suspension, tires and wheels need to be considered but you can raise the GVWR by replacing/upgrading these components.
Phil
blijil said
06:22 PM Jun 4, 2012
We upgraded 5200# axles to 6000# axles on our cedar creek after the were bent on a rough road in the states after a perfectly good trip to Alaska in 2009. It only required new wheels from 6 lugs to 8 lugs but the same tires were adequate as was the suspension etc. That being said we do not overload the rig above the GVW rating because support beams etc are designed to that figure with appropriate margins of safety. Also you have to consider your GCVW on your tow vehicle as well as rear axle limit on the tow vehicle. This is not an all you got to do type of thing.
That being said the axle upgrade adds a significant safety factor in your axle strength for less than optimum road conditions which do stress the axle.
Larry
Howard said
12:34 AM Jun 6, 2012
The axles are a limiting factor on the RV's maximum weight - the Gross Vehicle Weight Rating (GVWR). However, there are other engineering factors in the construction as well.
You cannot change the GVWR number provided on the sticker by the manufacturer no matter what you do. Only the manufacturer can change the number, and that's not something they are prone to do.
However, you can increase your practical load capacity by upgrading all your running gear - axles, wheels, tires, suspension, brakes, etc.
If you increase axles from 7,000 to 8,000 lbs without upgrading your wheels and tires and brakes, you accomplish increased axle strength but the axle weight ratings are limited by the weakest component on the axle. In other words, an 8,000 lb axle that has 3,750 lb max rating tires is in effect only a 7,500 lb axle.
So, if you are talking about changing the GVWR on the sticker, you can't do that. But if you are talking about increasing actual load carrying capacity, yes you can do that by upgrading axles IF you also upgrade all the components that make up the complete axle assembly. However, you may then be limited by the capacity of your suspension, so it may also need to be upgraded.
We've upgraded everything on our fifth wheel - suspension, axles, tires, rims, brakes, etc. It wasn't cheap, but it was a lot better than buying a new rig. And now we have additional safety cushion and less stress on the frame (due to better suspension), so the investment should make our home last years longer.
Hope I answered your question in there somewhere.
FastEagle said
04:20 AM Jun 8, 2012
The following is a quote from the NHTSA Q&A RV trailer section. It has some information that may be of interest here.
“The FMVSS have requirements for the manufacturer to use proper tires and rims for the gross axle weight rating (GAWR) and the gross vehicle weight rating (GVWR). The manufacturer may determine the GVWR by adding cargo capacity (if any) to the curb weight of the vehicle as manufactured. The wise consumer, before purchase, will determine if the vehicle has sufficient cargo capacity to carry the weight of water, additional equipment (such as televisions, and microwave ovens), and luggage. The manufacturer’s certification label must show the GVWR. The GVWR must not be exceeded by overloading the vehicle. There is little the government can do to assist a consumer who has purchased a vehicle that has insufficient cargo capacity for its intended use.”
A serious item that should be thoroughly discussed by the seller and buyer before signing the sales agreement.
FastEagle
canuck said
02:48 AM Jun 10, 2012
Thanks all for the replies. Much to learn before we start FT next year!
Hi,
Are the axles on a 5er limiting issue of the posted manufacter max weight? Can you raise the limits by changing axles? (eg. 7000lbs to 8000lbs) The brakes could also be a problem.
Scott
Phil
We upgraded 5200# axles to 6000# axles on our cedar creek after the were bent on a rough road in the states after a perfectly good trip to Alaska in 2009. It only required new wheels from 6 lugs to 8 lugs but the same tires were adequate as was the suspension etc. That being said we do not overload the rig above the GVW rating because support beams etc are designed to that figure with appropriate margins of safety. Also you have to consider your GCVW on your tow vehicle as well as rear axle limit on the tow vehicle. This is not an all you got to do type of thing.
That being said the axle upgrade adds a significant safety factor in your axle strength for less than optimum road conditions which do stress the axle.
Larry
The axles are a limiting factor on the RV's maximum weight - the Gross Vehicle Weight Rating (GVWR). However, there are other engineering factors in the construction as well.
You cannot change the GVWR number provided on the sticker by the manufacturer no matter what you do. Only the manufacturer can change the number, and that's not something they are prone to do.
However, you can increase your practical load capacity by upgrading all your running gear - axles, wheels, tires, suspension, brakes, etc.
If you increase axles from 7,000 to 8,000 lbs without upgrading your wheels and tires and brakes, you accomplish increased axle strength but the axle weight ratings are limited by the weakest component on the axle. In other words, an 8,000 lb axle that has 3,750 lb max rating tires is in effect only a 7,500 lb axle.
So, if you are talking about changing the GVWR on the sticker, you can't do that. But if you are talking about increasing actual load carrying capacity, yes you can do that by upgrading axles IF you also upgrade all the components that make up the complete axle assembly. However, you may then be limited by the capacity of your suspension, so it may also need to be upgraded.
We've upgraded everything on our fifth wheel - suspension, axles, tires, rims, brakes, etc. It wasn't cheap, but it was a lot better than buying a new rig. And now we have additional safety cushion and less stress on the frame (due to better suspension), so the investment should make our home last years longer.
Hope I answered your question in there somewhere.
The following is a quote from the NHTSA Q&A RV trailer section. It has some information that may be of interest here.
“The FMVSS have requirements for the manufacturer to use proper tires and rims for the gross axle weight rating (GAWR) and the gross vehicle weight rating (GVWR). The manufacturer may determine the GVWR by adding cargo capacity (if any) to the curb weight of the vehicle as manufactured. The wise consumer, before purchase, will determine if the vehicle has sufficient cargo capacity to carry the weight of water, additional equipment (such as televisions, and microwave ovens), and luggage. The manufacturer’s certification label must show the GVWR. The GVWR must not be exceeded by overloading the vehicle. There is little the government can do to assist a consumer who has purchased a vehicle that has insufficient cargo capacity for its intended use.”
A serious item that should be thoroughly discussed by the seller and buyer before signing the sales agreement.
FastEagle