Hello,
I'm recently retired. My wife and I have decided to sell out and go RVing full time. I'm just getting starting to seriously assess a purchase to make this dream a reality. After much discussion we are leaning toward a fifth wheel. I first wanted to understand towing capacities to be able to determine what size truck/fifth wheel would be a match as I will have to purchase both. After several hours of visiting web sites and videos I'm beginning to think I should have gone with a motor home!!! Every calculation example I've found either uses confusing terminology or asks for data in a manner that I can't find or understand. I would much rather understand how to solve the problem than fill out an on-lin calculator but either this information is very confusing or I'm getting thick!
The question is if I buy a certain truck, will I be able to safely pull a particular fifth wheel based on mfg specs. So, I'm hoping someone out there more knowledgeable might validate the analysis. All data is in lbs. Here is the given information
Tow Vehicle (Chevy 3500 diesel specs)
Curb weight: 7,539 Truck dry vehicle weight - no load, no fuel
Max Payload: 11,420 Believe this is also known as the truck GVWR
Payload: 4,036 GVWR-Curb weight. The actual math says the payload should be 3881. I don't know why these wouldn't agree but the 4,036 is the MFR data
GCWR 25,300 Max weight rating of trailer, truck and loadings (people, water, cargo etc)
5th Trailering: 17,200 Max Trailer capacity
Fifth Wheel (from Keystone 35Ft Avalanche data)
Shipping Wt 11,420 Also known as dry weight
Carrying Cap 3,580
GVWR: 15,000 Not provided but by definition, it should be the shipping wt + carrying capacity. From my reading this is also known as the GAWR for the trailer
Hitch Wt 2,240 Weight of the Pin on the truck.
Given the above information, the question is can the fifth wheel be safely towed. From my reading there are three concerns:
1. Is the towing capacity of the truck adequate
2. The Gross vehicle weight of the truck must not exceed the GVWR of the truck and
3. The Gross Combined weight of the trailer and truck must not exceed the GCWR of the truck
1. Towing Capacity. This was the most straight forward. Towing capacity of the 3500 Chevy is listed at 17,200 lbs. The fifth wheel if maxed out with cargo weight is 15,000. The difference between the tow is 2,200 lbs. Plenty of margin to tow a heavier fifth wheel in the future.
2. GVW of the tow vehicle must not exceed its GVWR or max payload. GVW is the truck curb weight+ people + cargo + fuel (7/bs/gal)+Pin Weight or Hitch weight. Therefore:
Curb Wt: 7,539
People: 600 (estimating 3 people 200lbs each)
Cargo 50 (estimate)
Fuel 252 (36 gal of diesel@ 7lbs/gal)
Pin Wt 2,240
_____
Total 10,681 GVWR is 11420 (11420-10681=739)
It's OK but 739 is only 6% of the rating. The only way I understand to improve this is to purchase higher rated tires or some other truck modification. Am I wrong in being concerned that I could be close to exceeding the GVWR. It seems that if I were to buy a larger RV than the 35 ft example in the future I could be in trouble. Is the analysis valid?
3. Gross Combined Weight of truck and trailer cannot exceed the GCWR of the truck. Weight of trailer: This would be the dry weight of the trailer plus cargo and water.
Shipping weight 11,430 Dry Weight
Cargo 800 Safe estimate of cargo: clothing,equipment,stuff
Water 1,643 Worst case scenario, all water tanks full (66+49+83=198 gal@ 8.3;bs/gal)
______
Gross Trailer weight 13,873
Gross Truck weight 8,441 10,681 from item 1 above less the pin wt (2,240).
_______
Combined weight 22,314 Truck GCWR = 25,300 (25,300-22314=2,986)
2,986 is plenty of margin
What I would welcome would be some comments on whether I've analyzed this correctly and what flaws in the methodology exist, if any. Should I be concerned with Item 2. It would seem a larger 5th with heavier tongue weight would put me over the edge.
Thanks and look forward to any comments.
Sorry about the format. When copied over from word it was a mess and inadvertently submitted. Tried to clean up as much as I could
I'm recently retired. My wife and I have decided to sell out and go RVing full time. I'm just getting starting to seriously assess a purchase to make this dream a reality. After much discussion we are leaning toward a fifth wheel. I first wanted to understand towing capacities to be able to determine what size truck/fifth wheel would be a match as I will have to purchase both. After several hours of visiting web sites and videos I'm beginning to think I should have gone with a motor home!!! Every calculation example I've found either uses confusing terminology or asks for data in a manner that I can't find or understand. I would much rather understand how to solve the problem than fill out an on-lin calculator but either this information is very confusing or I'm getting thick!
The question is if I buy a certain truck, will I be able to safely pull a particular fifth wheel based on mfg specs. So, I'm hoping someone out there more knowledgeable might validate the analysis. All data is in lbs. Here is the given information
Tow Vehicle (Chevy 3500 diesel specs)
Curb weight: 7,539 Truck dry vehicle weight - no load, no fuel
Max Payload: 11,420 Believe this is also known as the truck GVWR
Payload: 4,036 GVWR-Curb weight. The actual math says the payload should be 3881. I don't know why these wouldn't agree but the 4,036 is the MFR data
GCWR 25,300 Max weight rating of trailer, truck and loadings (people, water, cargo etc)
5th Trailering: 17,200 Max Trailer capacity
Fifth Wheel (from Keystone 35Ft Avalanche data)
Shipping Wt 11,420 Also known as dry weight
Carrying Cap 3,580
GVWR: 15,000 Not provided but by definition, it should be the shipping wt + carrying capacity. From my reading this is also known as the GAWR for the trailer
Hitch Wt 2,240 Weight of the Pin on the truck.
Given the above information, the question is can the fifth wheel be safely towed. From my reading there are three concerns:
1. Is the towing capacity of the truck adequate
2. The Gross vehicle weight of the truck must not exceed the GVWR of the truck and
3. The Gross Combined weight of the trailer and truck must not exceed the GCWR of the truck
1. Towing Capacity. This was the most straight forward. Towing capacity of the 3500 Chevy is listed at 17,200 lbs. The fifth wheel if maxed out with cargo weight is 15,000. The difference between the tow is 2,200 lbs. Plenty of margin to tow a heavier fifth wheel in the future.
2. GVW of the tow vehicle must not exceed its GVWR or max payload. GVW is the truck curb weight+ people + cargo + fuel (7/bs/gal)+Pin Weight or Hitch weight. Therefore:
Curb Wt: 7,539
People: 600 (estimating 3 people 200lbs each)
Cargo 50 (estimate)
Fuel 252 (36 gal of diesel@ 7lbs/gal)
Pin Wt 2,240
_____
Total 10,681 GVWR is 11420 (11420-10681=739)
It's OK but 739 is only 6% of the rating. The only way I understand to improve this is to purchase higher rated tires or some other truck modification. Am I wrong in being concerned that I could be close to exceeding the GVWR. It seems that if I were to buy a larger RV than the 35 ft example in the future I could be in trouble. Is the analysis valid?
3. Gross Combined Weight of truck and trailer cannot exceed the GCWR of the truck. Weight of trailer: This would be the dry weight of the trailer plus cargo and water.
Shipping weight 11,430 Dry Weight
Cargo 800 Safe estimate of cargo: clothing,equipment,stuff
Water 1,643 Worst case scenario, all water tanks full (66+49+83=198 gal@ 8.3;bs/gal)
______
Gross Trailer weight 13,873
Gross Truck weight 8,441 10,681 from item 1 above less the pin wt (2,240).
_______
Combined weight 22,314 Truck GCWR = 25,300 (25,300-22314=2,986)
2,986 is plenty of margin
What I would welcome would be some comments on whether I've analyzed this correctly and what flaws in the methodology exist, if any. Should I be concerned with Item 2. It would seem a larger 5th with heavier tongue weight would put me over the edge.
Thanks and look forward to any comments.
Sorry about the format. When copied over from word it was a mess and inadvertently submitted. Tried to clean up as much as I could