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On Tue, 31 Oct 2006 18:43:02 -0600, "Ray O"
<rokigawaATtristarassociatesDOTcom> wrote:[color=blue]
>"Mark" <makolber@yahoo.com> wrote in message
>news:1162338578.378899.38460@e64g2000cwd.googlegroups.com...[/color]
[color=blue][color=green]
>>I just replaced the radiator on my 95 Camry 4 cyl. I used new hoses
>> for the upper and lower radiator feeds and 2 new hoses for the
>> transmission cooler. I had a little trouble with the new transmission
>> cooler hoses engaging them as far onto the fitting as I would like.
>> The clamp is defnintly on over the bump in the fitting. I believe
>> these hoses are not under high pressure.
>> Is this correct? How much pressure is on the trany fluid that passes
>> through the tranny cooler hoses?[/color]
>
>The ATF is not under high pressure when it is traveling to the transmission
>cooler. High pressure lines will not be held in place with a spring clamp
>and are usually threaded.
>
>The pressure going to the transmission cooler is probably under 20 PSI.[/color]

But remember that doesn't apply as a blanket rule to all cars, and
it's good that you thought to check.

As an example, on some old GM Powerglide transmissions the cooler
line pressure is low in Neutral and Drive - but it spikes to around
150-200 PSI when you shift into Reverse, and can blow cooler hoses
that aren't made to handle that much pressure.

Even at 150 PSI with 1/4" hose the hose fittings don't have to be
too special, besides having a positive retaning bump or 'arrowhead'
groove as a retainer, and the hose has to be clamped past the bump
with wide worm-drive clamps to make sure it can't come off.

(No 'wire spring' clamps, not enough clamping force.)

But when you get much higher in pressure than that, or larger hoses
that will see the effects sooner, you have to go to a mechanically
clamped hose fitting system of some sort. Notably the ones using the
Aeroquip design (or equivalent) if you want to field assemble the hose
and fittings.

They have a threaded mandrel 'nut' that clamps the outer sheath of
the hose into the fitting, so it can't pull out short of severe abuse
- things like a motor mount shearing and the hose tries to hold the
engine in the car...

--<< Bruce >>--