Re: [A/S] Transmission operating Temperature

["Harvey Barlow" <harveybarlow@xxxxxxxxxxxxxxxx>]

Jim,

I have read published tests in Trailer Life magazine and other publications
but don't remember the details.  I think I have read that automatic
transmission fluid life is shortened quickly as temperatures exceed 200
degrees but duration of that temperature is also a factor.  ATF that has
been heated changes from red to brown color and takes on a burned odor that
is easily distinguishable on the dipstick.

Amsoil's claims, while they may be accurate, are expressed in the interest
of selling you their products.  Back issues of Trailer Life or Truck Trends
magazine might be more objective sources of information.  Another source
might be the makers of aftermarket add-on transmission coolers.  Hayden is a
name that comes to mind.  A review of Camping World or other RV parts
retailer's websites or catalogs might produce a name or names of other
manufacturers.  You might be able to find them on the web.  Although their
interest would be in selling you their coolers, I think the manufacturers
have done extensive testing and can probably provide safe operating temps as
well as extremes at which fluid, and transmissions, can fail.

Other automatic transmission fluid manufacturers may also be able to answer
your questions.

Towing against a strong headwind, in hills or mountainous terrain, with the
automatic transmission making frequent forced downshifts under full torque
will rapidly increase transmission fluid temps.  So will long periods spent
maneuvering to park on soft ground requiring heavy throttle application.

Changing your transmission fluid and filter frequently when towing is cheap
insurance against failure.

Harvey