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Old 08-24-2009, 01:08 AM   #66 (permalink)
2000mc
herp derp Apprentice
 
Join Date: Oct 2008
Location: Lawrence, KS
Posts: 1,049

Saturn-sold - '99 saturn sc1
Team Saturn
90 day: 28.28 mpg (US)

Yukon - '03 GMC Yukon Denali
90 day: 13.74 mpg (US)
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Quote:
Originally Posted by Christ View Post
Imagine you're driving a large diesel - you're engine braking at or near redline. :P
i believe gm got rid of the redline on the tach for the duramax after a couple years because of customer complaints of engine overspeed when decelerating or braking, because it was being used for engine braking far beyond where the engine makes useful power.

from bulletin #02-07-30-004C

For the LB7 diesel engine, maximum engine speed immediately following a preselect or grade braking downshift can be as high as 4,000 RPM. After a grade braking downshift, if vehicle speed continues to increase, an upshift will occur at 4,800 RPM engine speed.
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