Switch pitch thought (was: Transmissions)

[mark grady]

I'll offer what little I know.

Supposedly, these were designed by Hydramatic to lessen the effects of
'creep' at a stop light in these top-of-the line cars.

Take that FWIW.

Mark Grady

'77 Kingsley
home from storage, in the driveway, gassed up and ready to leave on a trip
Yippee!

> -----Original Message-----
> From: Bruce Herrin
> To: GMC Digest
> Date: Thursday, May 20, 1999 9:59 PM
> Subject: GMC: Transmissions
>
>
> >Just been lurking for awhile, now its time to maybe start a controversy.
> >
> >Anybody have any experience with a switch pitch transmission. I know
> >that they generate a lot of heat,(in low range) but maybe with extra
> >cooling.....
> >
> >I have a 3.21(think that's the right number) final drive and I don't
> >know if I want to turn the extra RPM's all the time for an occasional
> >hill.
> >
> >Anyway its a fresh rebuild with a heavy duty torque converter and I
> >wouldn't have to use the switch.
> >
> >Bruce
> >77 Palm Beach
>

 

[bartz paul]

Bruce:

I know one individual who has a switch pitch transmission in his coach and
likes it. He activates it with a switch.

I'm told that you can leave it engaged for up to two minutes before worrying
about overheating the transmission, due to the increased torque converter
slippage.

Paul Bartz

From: Mark Grady [mailto:mgrady]
Sent: Thursday, May 20, 1999 11:29 PM
Subject: GMC: Switch pitch thought (was: Transmissions)

I'll offer what little I know.
Supposedly, these were designed by Hydramatic to lessen the effects of
'creep' at a stop light in these top-of-the line cars.
Take that FWIW.
From: Bruce Herrin
Date: Thursday, May 20, 1999 9:59 PM
Subject: GMC: Transmissions
Anybody have any experience with a switch pitch transmission. I know that
they generate a lot of heat, (in low range) but maybe with extra
cooling.....
I have a 3.21 (think that's the right number) final drive and I don't know
if I want to turn the extra RPM's all the time for an occasional hill.
Anyway its a fresh rebuild with a heavy duty torque converter and I wouldn't
have to use the switch.