thaimonkee

When i have the truck iding with the jake brake/engine brake swith on the engine makes a louder knocking noise. It immediately quiets down when i turn the swtich off. Im wonderng if this is normal since i just got the truck from a private owner.

Brian08Q35004x4

Yep

thaimonkee

Really? Thats good then. I was paranoid something was wrong. Whats the noise anyways?

Brian08Q35004x4

Variable Gate turbo motor changing the vane position when you turn it on. Why I do not know, but think that it is spring loaded and when it turned on it move it out slightly maybe for response time(less distance to move when actuated)Maybe someone else has a better explanation. Maybe with the thing off it locked so that it does not move and when you turn it on it unlocks and moves it out slightly so the locking mechanism is unlocked and is ready for the motor to move it when really turned on by the ECM. Have not had to replace one yet in 140k so I have not had the chance to take one apart to see why

Lil Dog

The EB can be used as a warm up feature for the engine. It will engage the EB at idle and even at high idle.. I use it all the time to get the engine up to temp faster.

The Variable Geometry Turbo doesn't use a spring IIRC. Its all positional servo controlled, ie the servo moves to precise positions based on voltage. The larger versions of the turbo use air actuated cylinders to do the same function.

thaimonkee

Cool. Thanks. Just making sure its normal.