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Post Info TOPIC: What is J2807?


RV-Dreams Family Member

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What is J2807?


I was able to find the J2807 2012-05-17 revision that would apply to all vehicles 2013 through 2016 certification.  There is a new revision 2016-02-04 that I was not able to find a free copy of and was not willing to pay $74.00 from SAE for the standard.  I will limit this posting to HD Trucks & Fifth Wheel trailers.

As a basic premise, the manufacturer will configure a given tow vehicle and fifth wheel trailer within in truck and trailer weight limits at a GCVWR, in accordance to the setup and performance described in the J2807 to obtain certification.  It appears that this is a self certification by the manufacture unlike a UL, CE, or NIST certification that utilizes a third party for certification or oversight.   The standard does allow for some exceptions for shifting weights for a given test setup or calculations if certain conditions are not met (for example not able to test at Davis Dam) but these appear to be minor.

I was not able to find J2638 but in general this is an SAE standard that describes the performance of a fifth wheel or gooseneck hitch up to 30,000 lbs gross trailer weight rating.  Per the section below I would expect there is a multiplier of the max hitch weight rating applied to detect if there is any permanent deformation or damage of the trailer coupler, hitch, or vehicle for purpose of establishing a safety factor for the desired hitch rating.

Scope

The standard defines the procedures for determining the GCVW for cars, SUV’s, and trucks up to 13,000 lbs GVWR.  Interesting so this standard shouldn’t apply to Ford F350/F450 Pickup, Chevy 3500, RAM 3500, or MDT & HDT trucks.....This should be the end of the post!  The 2016-02-04 standard expands this to 14,000 lbs GVWR.  As a side note this would explain to me why Class 4 & 5 trucks do not have the same horsepower and torque numbers as Class 3 trucks.  If this standard was extended to Class 4 & 5 trucks I think we would see the higher horsepower and torque engines in these trucks.

Tow Vehicle Weight & Configuration > 8,500 lbs.

  • Base Vehicle Curb Weight
  • 1 Driver 150 lbs.
  • 1 Passenger 150 lbs. front seat
  • 100 lbs optional equipment split evenly between axles
  • Tow Package or any required trailering components factory or aftermarket
  • Fifth Wheel Hitch over axle centerline or up to 2 inches forward of centerline of axle or per factory location

Trailer Standards

  • Tandem or Triple Axle
  • Not to exceed trailer axle weight ratings
  • Not to exceed tire weight ratings with max air pressure
  • Cargo Box Style
  • Corner radii no more than 6 inches
  • Torsion or leaf spring suspension
  • Tire load capacities defined by Tire & Rim Association Yearbook
  • Tire minimum tread depth 5/32 in.
  • Tires in good condition
  • Trailer ballast/Trailer/Truck should equal GCVWR
  • Trailer ballast placed in ‘ballast boxes’
  • Ballast Boxes secured in such a manor that ballast doesn’t move
  • Ballast equally distributed left & right
  • Fifth Wheel Tongue Weight = 20% +/- 1%

Fifth Wheel Structural Performance – Tow Vehicle

  • Inline with test procedure J2638
  • Ability to withstand load for 5 s
  • No Loss of attachment
  • Manufactures responsibility to pick the most capable model

Propulsion Performance

  • Level Road Acceleration 0 to 60 mph - 35 s for DRW
  • Level Road Acceleration 0 to 30 mph - 14 s for DRW
  • Level Road Acceleration 40 to 60 mph - 21 s for DRW
  • Launch on Grade 12% forward & reverse - 5 launches to 16 ft in 5 min
  • Min Speed on grade (Davis Dam) – 35 mph DRW
  • Drivetrain System Performance - No component failures, diagnostic codes, or warnings
  • Cooling System Performance – No component failures, diagnostic codes, warnings, or loss of fluids

Driving Conditions

  • 100 degrees F
  • A/C Max cold
  • Outside air
  • Full Blower

Handling Requirements are a bit complicated - lets say the combination should be stable in understeer with an induced lateral acceleration  - i.e. controllable in emergency lane changes

Braking Performance GCVW (trailer brakes disabled)

  • Remain within 11.5 ft lane
  • Stopping distance 20 to 0 mph - <= 80 ft
  • Parking Brake to hold GCWR on 12% grade upward and downward
  • No pedal force requirement
  • Brakes may be burnished prior to test

Personal Opinion

This is a standard enacted in an attempt to keep the manufactures honest and to provide some baseline comparison but I would not consider this a torture test.  The Davis Dam grade is ~5% over a little under 12 miles at a starting elevation of 500 ft and an ending elevation of 3500 ft.  Results from certifications show near highway speeds for the Davis Dam run without coming close to the 35mph minimum.  For a comparison the Ike Gauntlet that the TFL truck guys use is 8 miles long with an average 7% grade starting elevation ~8,000 ft and ending elevation ~11,000 ft.  They make the run with GCVW over 30,000 lbs at higher elevation and maintain near highway speeds. Other braking and acceleration tests do not seem extreme.

Furthermore I am surprised that Ford & Ram get away with their J2807 claims as it doesn't appear possible for them to meet the standard.  Helium in the tires and 19% tongue weight.

Ford F450 Class 3 Pickup

  • Gooseneck/fifth wheel rating 31,200 lbs.
  • 20% tongue weight = 6,240 lbs
  • Empty rear axle = 4,400 lbs
  • Total = 10,640 lbs. way over GRAW and GVW (lots of fudging to get these numbers to work)

RAM 3500

  • Gooseneck/fifth wheel rating 31,210 lbs.
  • 20% tongue weight = 6,242 lbs
  • 19% tongue weight allowed = 5930 lbs.
  • Empty rear axle = 3,600 lbs
  • Total 20% = 9,842 lbs. over GRAW and GVW
  • Total 19% = 9,530 lbs. under the GRAW rating

Andy



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RV-Dreams Family Member

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I can see Ford is over their rear axle ratings of only 9,100# but I don't see a problem with RAM's ratings at 19%. I may be wrong but I thought 15% was the minimum tongue weight for the gooseneck trailer? RAM's rear axle rating is 9,750#.

VERY interesting the 3500 RAM's numbers are better than the F450's.

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2015 RAM/Cummins/Aisin/4.10's/3500Dually

2016 Mobile Suites 39TKSB3 "Highly Elited"

32,950# combined



RV-Dreams Family Member

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Cummins12V98 wrote:

I can see Ford is over their rear axle ratings of only 9,100# but I don't see a problem with RAM's ratings at 19%. I may be wrong but I thought 15% was the minimum tongue weight for the gooseneck trailer? RAM's rear axle rating is 9,750#.

VERY interesting the 3500 RAM's numbers are better than the F450's.


The J2807 certification is just a new marketing number as you have pointed out.....the standard calls for 20% tongue weight +/- 1% as a buffer for 5th wheel and gooseneck trailers .... they just chose to use the buffer.  As for RAM using the 19% tongue weight they can easily up their towing number to 32,300 lbs. and they will if they need to.  9,750 lbs. - 3,600 lbs. = 6,150 / 0.19 = 32,368 lbs.

So I unofficially re-certify the RAM 3500 per J2807 to haul a trailer of 32,368 lbs.  

Andy 



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RV-Dreams Family Member

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I have been involved with helping define SAE & other standards and I have also developed and tested product that requires adherence to standards.  Most of the times experts in the industry sit on these steering committees to help develop the standard to better serve the industry.  My guess is that Ford, Chevy, Ram, Toyota, etc. have members sitting on these committee and I don't believe that they would recommend standards that would lower their towing numbers.  

This standard is supposed to help the consumer buy with confidence a truck that can meet the towing number claims.  I have been in the driver seat going up a grade at 35 mph foot to the floor white knuckling it......that truck was over matched for the task yet it would have passed the J2807 standard.  Stopping on a grade is another concern that this standard doesn't address except that when you do get stopped the emergency brake should hold the load.

What I would change to the standard to help the consumer!

Changes/Additions

  • Fifth Wheel/Gooseneck Tongue Weight increase from 20% to 22% +/-1%
  • Maximum suspension squat <= 3 inches at GCVW 
  • Min Speed on grade (Davis Dam) increase from 35 to 45 mph DRW
  • 5% Grade Acceleration (Davis Dam) 0-40 mph = 80 s
  • 5% Grade Acceleration (Davis Dam) 20-40 mph = 45 s
  • 5% Grade stopping distance 20-0 mph <= 200 ft (trailer brakes disabled)

Andy



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RV-Dreams Family Member

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While I  won't dispute your numbers, I'm wondering why or your methodology for picking a Ford F-450 as a comparison to a Ram 3500. Why wouldn't you have picked a F-350?

In evaluating Ford's published data the 450 has a GWAR of 9100 lbs vs the 350 at 9650 lbs. Their own data also shows that the front axle GWAR is 5940 lbs for both the 350 and the 450. However the GCWR for a similar equipped 350 is 35000 lbs, where the 450 is at 40400 lbs both when towing a gooseneck/5th wheel.

Again when comparing apples to apples (as opposed to apples to oranges) the stats I have provided are for 4x4 Supercrew trucks with a 4.30 rear axle ratio.

So from what I can surmise by Fords own data, to me something is amiss. The front axle rating are the same, the 350 has a higher rear axle rating by 550 lbs then the 450, but yet the 450 has a higher GCWR by 5400 lbs. This leads me to believe that the two vehicles were rated under different standards.



-- Edited by Rickl on Friday 18th of March 2016 09:09:32 AM



-- Edited by Rickl on Friday 18th of March 2016 09:11:29 AM

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2015 Ram 3500 6.7L DRW



RV-Dreams Family Member

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The Class 3 F450 Pickup was certified to J2807 and the F350 was not.....my opinion is that the J2807 2015-2016 F350 rear axle rating would also be 9,100 lbs using the J2807 standard.  The Class 3 F450 pickup does compete with the Ram 3500.  The F450 Cab & Chassis is a class 4 commercial truck and is a different truck.

Here is some additional information on why the numbers are different that was posted in the F350 vs. F450.

Found this on a Ford Media release that describes some of the changes with the towing capacity reaffirming what I thought/said above.  It is not that the axle rating was lowered but the truck got heavier applying the J2807 ... result is adding an extra 400 lbs in base curb weight & people and the lowering of payload 150 lbs. from 5,450 lbs. to 5,300 lbs .... 9,650 - 550 = 9,100 lbs....this would indicate the DRW F350's J2807 rear axle rating would also be 9,100 lbs.

Full link here https://media.ford.com/content/fordmedia/fna/us/en/news/2014/09/02/ultimate-towing-machine-2015-ford-f-450-rated-best-in-class.pdf

 

Ford previously determined F-450 pickup towing capacity using

rigorous internal testing standards exclusively. Now it has added

SAE J2807 test procedures, reaffirming the F-450 pickup rating.

F-450 passed the additional tests with 31,200 pounds in tow, just

as it passed Ford internal tests.

SAE J2807 requires the vehicle to be loaded with about 400

pounds more weight than Ford’s internal test (two passengers

instead of one, and base curb weight instead of minimum curb

weight), but the weight addition has no effect on F-450 towing

capacity. Using either standard, F-450 has best-in-class towing

capacity of 31,200 pounds.

As a result of the J2807 test results, Ford is also increasing the

F-450 pickup’s already best-in-class gross combined weight rating

from 40,000 pounds to 40,400 pounds – topping the nearest

competitor by 2,500 pounds

Payload rating changes

Ford is migrating to the J2807 standard when it introduces allnew

vehicles and will use base curb weight, rather than minimum

curb weight, to determine payload ratings for all of its pickup

trucks. The change will align Ford’s payload rating practices with

other manufacturers to make it easier for customers to compare

vehicles.

Using base curb weight, maximum payload for the 2015 F-450

pickup goes from 5,450 pounds to 5,300 pounds.



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RV-Dreams Family Member

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Rickl wrote:

While I  won't dispute your numbers, I'm wondering why or your methodology for picking a Ford F-450 as a comparison to a Ram 3500. Why wouldn't you have picked a F-350?

In evaluating Ford's published data the 450 has a GWAR of 9100 lbs vs the 350 at 9650 lbs. Their own data also shows that the front axle GWAR is 5940 lbs for both the 350 and the 450. However the GCWR for a similar equipped 350 is 35000 lbs, where the 450 is at 40400 lbs both when towing a gooseneck/5th wheel.

Again when comparing apples to apples (as opposed to apples to oranges) the stats I have provided are for 4x4 Supercrew trucks with a 4.30 rear axle ratio.

So from what I can surmise by Fords own data, to me something is amiss. The front axle rating are the same, the 350 has a higher rear axle rating by 550 lbs then the 450, but yet the 450 has a higher GCWR by 5400 lbs. This leads me to believe that the two vehicles were rated under different standards.



-- Edited by Rickl on Friday 18th of March 2016 09:09:32 AM



-- Edited by Rickl on Friday 18th of March 2016 09:11:29 AM


 It's called smoke and mirrors.  Ford uses any numbers they want for the F250/350 but the numbers they use for the F450 are SAE rated.  2017 Ford will have to actually back up what they claim.  RAM has been using SAE for a while now.



__________________

2015 RAM/Cummins/Aisin/4.10's/3500Dually

2016 Mobile Suites 39TKSB3 "Highly Elited"

32,950# combined

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