Written by gary on November 24th, 2010

Toyota Tundra and Tacoma trucks are meeting new towing standard guidelines early.tundra towing trailer

The Society of Automotive Engineers decided a few years ago to form a task force to determine which procedures and regulations should be instituted to make sure each automaker gives the consumer the most accurate — and comparable — tow rating.

The idea is to make sure each manufacturer uses the same testing procedures so the consumer can get the best and most accurate information. To date, there is only a proposed standard, called J2807, that is still in formal deliberations; however, there is something of a “gentlemen’s agreement” among all manufacturures that the 2013 model year will be the target date to have these processes and procedures in place across the board.

Toyota is adopting these guidelines early. All of its 2011 models already comply with J2807. Of note, many of the new tow ratings on identically equipped vehicles from the previous year have gone down.tow chart

This is largely because the new SAE procedures are quite thorough and exhausting, and they include a rather challenging handling requirement that many automakers had not considered. The end result for truck buyers is that from one year to the next, they might see some changes in the maximum tow ratings of their favorite pickups (usually down, but possibly in some cases up). And it may not mean the vehicle has changed in any way, just that it is being tested more thoroughly than before.

Truck enthusiasts who keep a pulse on Truck Towing Capacities may be familiar with the wars over maximum towing capacity that have heated up over the past 10 years in the half-ton and heavy-duty arenas. Ford, GM and Ram have magically upped their rating numbers at different points with seemingly little or no changes to a specific frame or suspension. Also, they’ve all been guilty of using their maximum towing numbers — which typically relate to a very specific low-volume vehicle — to gain some type of advertising advantage when every knowledgeable truck enthusiast knew the numbers applied only to a specific model and not across the lineup.

That is partly why SAE finally stepped in to try to standardize the testing and rating procedures, making sure a truck-to-truck comparison can be done. Every cab and powertrain combination, including some of the more popular option packages, will need to be tested for ratings. The ultimate benefit is for the consumer, as automakers will be forced to play (or tow) on an equal basis, with more transparency.

In Toyota’s case, the tow rating of most of the vehicles tested went down a proportional amount across the lineup — for Tundra, about 400 pounds. In other cases, especially with midsize and large SUVs, the drop in towing capacity was closer to 100 or 200 pounds.

Here is a brief, but not thorough or exhaustive, description of some of the J2807 testing procedures:

1) A vehicle must be able to pull a trailer of a designated weight (and shape) up a Davis Dam simulation at a minimum speed of 40 mph in ambient temperatures of 101 degrees with the maximum air conditioning turned on at the full fan setting. The run must be done several times, and there must be and no overheating, no puking and no trouble codes.

2) All trailers must adhere to the same specifications as set forth by the J2807 procedures. They must be boxed with a flat face of a specified height and width.

3) On a level road, the vehicle and trailer combination must be able to accelerate from zero to 30 mph in less than 12 seconds, zero to 60 mph in 30 seconds, and run 40-60 mph in less than 18 seconds.

4) A vehicle and trailer must be able to launch a minimum distance of 16 feet from a stop up a 12-percent grade five times in five minutes, measured both in Drive and Reverse.

5) A vehicle and trailer combination must be able to stay in control and in its original lane when panic stopping from 80 mph. In those cases where the combination cannot attain that speed, the vehicle’s upper limit will suffice.

6) The vehicle and trailer combination must be able to perform the necessary low-speed turning circle test with the minimum of understeer or trailer push.

7) For trailers weighing less than 3,000 pounds, the vehicle must be able to stop the combination (without trailer brakes) in 35 feet or less. If the trailer is more than 3,000 pounds, the distance is 80 feet.

8) The parking brake on the towing vehicle must be able to hold the trailer (without trailer brakes) pointed up and down a 12-percent grade.

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