GMC 2004 Sierra - Manual (Page 123)

Tow/Haul Mode
(Automatic Transmission)
Your vehicle may be equipped with a Tow/Haul mode.
The selector button is located on the end of the
column shift lever. You can use this feature to assist
when towing or hauling a heavy load. Turn Tow/Haul on
and off by pressing the button until the Tow/Haul
indicator light illuminates on the instrument panel. See
“Tow/Haul Mode
″
under Towing a Trailer on page 4-70
for more information.
Overdrive Disable
(Allison Transmission
® )
If your vehicle has an Allison Transmission ® you may
have the overdrive disable feature. The overdrive disable
feature prevents the transmission from shifting into
fifth (5) gear. The selector button is located on the end of
the column shift lever. You can turn overdrive disable on
and off by pressing and holding the button at the end of
the column shift lever until the indicator light, on the
instrument panel, illuminates.
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