[A/S] Why no Duramax/Allison in the Suburban

["Oliver Filippi" <ofilippi@xxxxxxxxxxxx>]

Dick,

There is no question that the Duramax/Allison is a terrific tow vehicle
powertrain.

Shortly after this product came out, I had the opportunity to talk to a
Chevrolet engineer and ask her (yes, it was a lady engineer) when this
powertrain was going to be available in a Suburban.

She told me that it wasn't a simple fix (but not that complicated, either).
The Duramax produced so much torque that it would destroy a lesser
transmission than the Allison, so both the engine and the transmission would
have to be installed in the Burb.

The Allison transmission is significantly larger in diameter than the
transmissions used in the Suburban and would not fit.  To make it fit would
require a deeper cross brace under the transmission and a revised floor pan
in the passenger compartment.  Also, the Duramax was taller, so a higher
hood would also be needed.

This is why the Duramax/Allison is only available on the HD version of the
pickup.  It has a heavier frame (and cross member, and higher hood in the
front). At the time, Duramax production was limited, and GM could only meet
the anticipated pickup sales forecast.  Thus there was not a lot of pressure
to increase Duramax sales.

Obviously, things have changed. The question now is, Has the redesigned,
current Suburban anticipated fitting the Duramax/Allison into it?  I don't
know the answer to that question.

I would be a little leery of a "beefed up" Hydramatic connected to a
downsized Duramax. This sort of thing sounds to me like a one way ticket to
trouble.

Oliver Filippi