The HDPP misconception
09-26-2017, 07:43 PM
#21
This makes sense though. HDPP trucks were GCWR limited and that didnt change for 2018, the non HDPP trucks were GVWR limited and that also didnt change. So 5th wheel towing probably didnt change for either while conventional did.
Conversely, a non-HD payload 2017 2x4 crew cab has a 1600 lb lower 5th wheel tow capacity. I imagine this is because the non-HD truck didnt have enough payload to support the 15% pin weight, the 250 lb hitch, and the 300 lbs of passengers and not exceed GVWR or GAWR. Since the conventional hitch is only 10% and only has a 75 lb hitch it leaves more room for a heavier trailer without exceeding payload.
The HDPP trucks GCWR didnt change for 2018, so the towing didnt change. The 5th wheel capability of a non-HD truck probably didnt increase because they were payload limited before and still are now. GCWR increased because they were able to use a 10% tongue weight conventional trailer and still slide in without exceeding payload.
All in all, we are simply arguing over the nuances of J2807 which is there to tell the MFG's how to calculate the maximum trailer weight. Its a guide for them to publish a max trailer weight without being dishonest, but what it really does is get them to figure out the maximum GCWR under supervision. It is then Fords job to back calculate the max trailer weight using the assumptions from J2807, the GCWR they determined with testing, and the published payload capacity/curb weight of their trucks. In the end, when I hook up a trailer to my truck I am limited by the GCWR am I not? If I buy a 2018 XL 2x4 crew cab then I could theoretically tow 13,200 lbs but if I buy the same truck in a Platinum super duper luxo-yacht 4x4 edition then I can only tow 12000 lbs even though GCWR is the same. The chart wont tell you that though.
Alternately, if I found a carbon fiber 5th wheel hitch that only weighs 20 lbs can I not tow MORE than what ford calculates as the maximum trailer weight? I still stay under GCWR and GVWR because my hitch is 230 lbs lighter than what J2807 assumes. What if I dont want my wife to come with me? Can i not use that assumed 150 lbs towards payload and increased trailer weight? What if ford started drilling holes in the beds to reduce the curb weight of their trucks, would that not count towards higher trailer and payload weights?
Last edited by mass-hole; 09-26-2017 at 08:20 PM.
09-26-2017, 07:45 PM
#22
I never said they were not knowledgable. I said they have no specific training related to what they are selling. Some may in fact be highly knowledgable.
I said never listen to a salesman as they are just that, a salesmen. You as the purchaser are responsible for knowing your needs and how that relate to the vehicle you are purchasing. To many vehicle salespeople have made statement during a sale that were erroneous to say the least. We have see that over and over again from people on this site alone.
I still stand by my statement that HDPP stands alone from towing is an error.
I said never listen to a salesman as they are just that, a salesmen. You as the purchaser are responsible for knowing your needs and how that relate to the vehicle you are purchasing. To many vehicle salespeople have made statement during a sale that were erroneous to say the least. We have see that over and over again from people on this site alone.
I still stand by my statement that HDPP stands alone from towing is an error.
09-26-2017, 08:01 PM
#23
I havent seen a towing selector for the 2018, is there one? Thats the only place I have seen where they separate conventional and 5th wheel tow ratings.
This makes sense though. HDPP trucks were GCWR limited and that didnt change for 2018, the non HDPP trucks were GVWR limited and that also didnt change. So 5th wheel towing probably didnt change for either while conventional did.
The 15% pin weight thing doesnt prove anything though. The 2017 HDPP trucks were GCWR limited, not payload limited, when calculating at 15% pin weight so they had basically the same conventional and 5th wheel tow capacity(100 lb difference). I assume that difference was related to the required equipment to tow the 5th wheel(hitch, etc). Looks like J2807 assumes a 75lb for a conventional hitch and 250 lbs for a 5th, that extra weight subtracts from the GCWR.
Conversely, a non-HD payload 2017 2x4 crew cab has a 1600 lb lower 5th wheel tow capacity. I imagine this is because the non-HD truck didnt have enough payload to support the 15% pin weight, the 250 lb hitch, and the 300 lbs of passengers and not exceed GVWR or GAWR. Since the conventional hitch is only 10% and only has a 75 lb hitch it leaves more room for a heavier trailer without exceeding payload.
The HDPP trucks GCWR didnt change for 2018, so the towing didnt change. The 5th wheel capability of a non-HD truck probably didnt increase because they were payload limited before and still are now. GCWR increased because they were able to use a 10% tongue weight conventional trailer and still slide in without exceeding payload.
All in all, we are simply arguing over the nuances of J2807 which is there to tell the MFG's how to calculate the maximum trailer weight. Its a guide for them to publish a max trailer weight without being dishonest, but what it really does is get them to figure out the maximum GCWR under supervision. It is then Fords job to back calculate the max trailer weight using the assumptions from J2807, the GCWR they determined with testing, and the published payload capacity of their trucks. In the end, when I hook up a trailer to my truck I am limited by the GCWR am I not? If I buy a 2018 XL 2x4 crew cab then I could theoretically tow 13,200 lbs but if I buy the same truck in a Platinum super duper luxo-yacht 4x4 edition then I can only tow 12000 lbs even though GCWR is the same.
Alternately, if I found a carbon fiber 5th wheel hitch that only weighs 20 lbs can I not tow MORE than what ford calculates as the maximum trailer weight? I still stay under GCWR and GVWR because my hitch is 230 lbs lighter than what J2807 assumes. What if I dont want my wife to come with me? Can i not use that assumed 150 lbs towards payload and increased trailer weight?
This makes sense though. HDPP trucks were GCWR limited and that didnt change for 2018, the non HDPP trucks were GVWR limited and that also didnt change. So 5th wheel towing probably didnt change for either while conventional did.
The 15% pin weight thing doesnt prove anything though. The 2017 HDPP trucks were GCWR limited, not payload limited, when calculating at 15% pin weight so they had basically the same conventional and 5th wheel tow capacity(100 lb difference). I assume that difference was related to the required equipment to tow the 5th wheel(hitch, etc). Looks like J2807 assumes a 75lb for a conventional hitch and 250 lbs for a 5th, that extra weight subtracts from the GCWR.
Conversely, a non-HD payload 2017 2x4 crew cab has a 1600 lb lower 5th wheel tow capacity. I imagine this is because the non-HD truck didnt have enough payload to support the 15% pin weight, the 250 lb hitch, and the 300 lbs of passengers and not exceed GVWR or GAWR. Since the conventional hitch is only 10% and only has a 75 lb hitch it leaves more room for a heavier trailer without exceeding payload.
The HDPP trucks GCWR didnt change for 2018, so the towing didnt change. The 5th wheel capability of a non-HD truck probably didnt increase because they were payload limited before and still are now. GCWR increased because they were able to use a 10% tongue weight conventional trailer and still slide in without exceeding payload.
All in all, we are simply arguing over the nuances of J2807 which is there to tell the MFG's how to calculate the maximum trailer weight. Its a guide for them to publish a max trailer weight without being dishonest, but what it really does is get them to figure out the maximum GCWR under supervision. It is then Fords job to back calculate the max trailer weight using the assumptions from J2807, the GCWR they determined with testing, and the published payload capacity of their trucks. In the end, when I hook up a trailer to my truck I am limited by the GCWR am I not? If I buy a 2018 XL 2x4 crew cab then I could theoretically tow 13,200 lbs but if I buy the same truck in a Platinum super duper luxo-yacht 4x4 edition then I can only tow 12000 lbs even though GCWR is the same.
Alternately, if I found a carbon fiber 5th wheel hitch that only weighs 20 lbs can I not tow MORE than what ford calculates as the maximum trailer weight? I still stay under GCWR and GVWR because my hitch is 230 lbs lighter than what J2807 assumes. What if I dont want my wife to come with me? Can i not use that assumed 150 lbs towards payload and increased trailer weight?
09-26-2017, 08:36 PM
#24
Out of curiosity I checked RAM, Chevy, Toyota, and Nissan for a rated pin weight. All but Nissan just quotes the SAE j2807 15%, Nissan gives a max rated pin weight for each trim level Titan. So it’s not just Ford playing the numbers game most are doing the same thing. This is the nonsense the SAE tests was supposed to stop but it continues.
09-27-2017, 01:15 AM
#25
Out of curiosity I checked RAM, Chevy, Toyota, and Nissan for a rated pin weight. All but Nissan just quotes the SAE j2807 15%, Nissan gives a max rated pin weight for each trim level Titan. So it’s not just Ford playing the numbers game most are doing the same thing. This is the nonsense the SAE tests was supposed to stop but it continues.
09-27-2017, 08:20 AM
#27
Senior Member
Exactly. There is no factual basis to support the claim that the 15% tongue weight of the stated tow rating is the limit for the pin weight on that truck.
This is especially true when referring to the 5.0 HDPP. The same truck with the 3.5EB has a higher 5th wheel tow rating, but the truck is the same other than the engine...same GVWR, same payload (other than the difference in weight of the engines), same axle weight ratings. What changes is the GCWR.
The most logical conclusion is that GCWR, not pin weight, is truly the limiter. Ford doesn't list a max pin weight, so what's the next limit you will hit? Either GVWR or RAWR.
A quote from page 2 the 2014 F-150 towing guide:
And from page 3 of the 2017 F150 towing guide
Slightly different wording, but both of these quotes indicate that the RAWR and GVWR are the limiters for the pin weight.
This is especially true when referring to the 5.0 HDPP. The same truck with the 3.5EB has a higher 5th wheel tow rating, but the truck is the same other than the engine...same GVWR, same payload (other than the difference in weight of the engines), same axle weight ratings. What changes is the GCWR.
The most logical conclusion is that GCWR, not pin weight, is truly the limiter. Ford doesn't list a max pin weight, so what's the next limit you will hit? Either GVWR or RAWR.
A quote from page 2 the 2014 F-150 towing guide:
• Trailer tongue (trailer king pin for 5th-wheel towing) load weight should be 10-15% (15-25% for 5th-wheel towing) of total loaded trailer weight. Make sure vehicle payload (reduce by
option weight) will accommodate trailer tongue (trailer king pin for 5th-wheel towing) load weight and weight of passengers and cargo added to towing vehicle. Addition of trailer tongue
(trailer king pin for 5th-wheel towing) load weight and weight of passengers and cargo cannot cause vehicle weights to exceed rear GAWR or GVWR. These ratings can be found on the
vehicle Safety Compliance Certification Label.
option weight) will accommodate trailer tongue (trailer king pin for 5th-wheel towing) load weight and weight of passengers and cargo added to towing vehicle. Addition of trailer tongue
(trailer king pin for 5th-wheel towing) load weight and weight of passengers and cargo cannot cause vehicle weights to exceed rear GAWR or GVWR. These ratings can be found on the
vehicle Safety Compliance Certification Label.
And from page 3 of the 2017 F150 towing guide
Trailer king pin load weight should be 15% of total loaded trailer weight. Make sure vehicle payload (reduce by option weight) will accommodate trailer king pin load weight and weight of
passengers and cargo added to towing vehicle. Addition of trailer tongue load weight and weight of passengers and cargo cannot cause vehicle weights to exceed rear GAWR or GVWR. These
ratings can be found on the vehicle Safety Compliance Certification Label.
passengers and cargo added to towing vehicle. Addition of trailer tongue load weight and weight of passengers and cargo cannot cause vehicle weights to exceed rear GAWR or GVWR. These
ratings can be found on the vehicle Safety Compliance Certification Label.
09-27-2017, 08:45 AM
#28
The factual basis is the SAE test which specifically sets pin at 15%. Fords rating is calculated from the max GCWR achieved with 15%. Single vehicle dynamics differs greatly from one that’s towing and with hdpp the CG of the truck needs to be considered and derated based on CG position. Bottom line Ford set the max towing with 15% pin weight not higher.
09-27-2017, 09:36 AM
#29
Senior Member
The factual basis is the SAE test which specifically sets pin at 15%. Fords rating is calculated from the max GCWR achieved with 15%. Single vehicle dynamics differs greatly from one that’s towing and with hdpp the CG of the truck needs to be considered and derated based on CG position. Bottom line Ford set the max towing with 15% pin weight not higher.
By your logic, one might conclude that if a vehicle is advertised going from 0-60mph in x seconds, then that vehicle isn't capable of physically/legally going faster than 60mph. In reality, it can (under some, not necessarily all circumstances) go faster, but 60mph was the parameter for the test.
09-27-2017, 09:57 AM
#30
Ford simply uses 15%, because that is the minimum required by the SAE testing guidelines. The general rule is 15% to help prevent sway. The 1575 number you listed makes no sense because other 5.0s can go up to 10800, or 1620 even using 15%, its common to see a lighter trailer with more pin weight too. While a Gooseneck horse trailer may have less than 15% and let non HDPP trucks hit their GCWR no problem. Its all about GVWR and GAWR.