Downshift or exhaust brake?
I was just thinking after reading a post about gas vs diesel trucks where somebody mentioned they liked diesel because of the exhaust brake. I've never had a diesel, always gas. If I come up to a long...
Forum Discussion
Turtle n Peeps wrote:ShinerBock wrote:Turtle n Peeps wrote:
All an exhaust brake does on a diesel is plug up the engine on the exhaust side. On a gas engine you have the same thing it's just on the intake side and is known as a throttle valve or a throttle body. A diesel does not have this because the intake tract is wide open.
This was true up until 2007 with the addition of DPF's and more aggressive EGR's. Many diesels now have an intake throttle valve right before the EGR valve to create a vacuum to pull exhaust gases through the the EGR system.
True. But my point was is doesn't matter if you dead head the engine on the intake or the exhaust; you're still dead heading the engine.
Sure it does. On the exhaust stroke you are blocking a much larger volume of heated expanded air. On the intake you are just trying to create a vacuum.
