Re: To Tow or Not To Tow


"GingerJools" <newsreader@xxxxxxxxxxx> wrote in message
news:ne7n83d5tjns61p1jm3t0paf70bvh55vqm@xxxxxxxxxx
On Mon, 2 Jul 2007 20:58:18 -0700, "Alan Robinson" <alr@xxxxxxx>
wrote:
. In an automatic transmission, transmission fluid is
pumped under pressure by a pump driven by the -engine- side of the
transmission, so if the engine's not running, no pressurised transmisssion
fluid. Many parts of the transmission are lubricated by this pressurised
fluid - and are not really designed to be lubricated only by fluid
splashing
around inside the housing. If the parts that are turned by the wheels are
lubed adequately by fluid thrown around by the gears, then it's towable -
if
some/all require pressurized lube, then it's not towable.

So it's more the luck of the draw that determines whether there's
enough turbulence generated by the moving gears? Not something to due
to a different "style" of auto tranny?

It can be luck of the draw, or a specific design decision - depends on where
being towed four-down landed on the manufacturer's list of priorities. It's
not just whether the moving parts throw enough lube around - it also depends
on whether that lube can get to the bearings that need it, and whether the
bearing is a type that -can- be splash-lubed rather than pressure lubed.


I would guess, now, that this is why some cars require that you stop
every 200 miles and run the engine for a short while. This would pump
more fluid into and around inside the housing?

Correct.


Of course, you can add a small electric pump that runs when you're towing,
and tow almost anything.

Hey! I _like_ this idea. Are we talking a lot of $$? I assume this
would void any warrantee...

Ginger

www.remcotowing.com for details about the most popular implementation - it's
not cheap, but it certainly widens the pool of vehicles that you can tow. I
don't know how auto warranties in Canada work - in the U.S., generally
speaking the car manufacturer would have to show that your add-on device was
a direct cause of the failure to be able to deny a warranty claim (which is
not the same thing as saying that they wouldn't try to weasel out of it
anyway....). Remco might be the best ones to ask - I'd imagine that if any
such thing had been tried, they would have heard about it.

Alan


.

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