Jake-Brake/Engine fan engaging

The fan engages to add to the engine braking,next time your at the shop you can get them to disengage it through the ECM.

 

it helps down hill alot but can be disengaged and if need be u can use the fan switch to engage it while going down a hill

 

I understand the fan is load and annoying, but I don't understand why most drivers hate engine fan on with engine braking. The engine fan actually absorbs 30-50 horsepower, believe it or not! So you have that much extra for free to help slow you down and save wear and tear on your brakes.

 

yeah but imagine the wear and tear on the fan hub and fan belts every time u jake even when the extra braking power is not needed

 

Not much more than having it engage all the time when the A/C is on.

 

so true ,just drive

 

The primary reason the fan is configured to come on during prolonged compression braking is because jake braking builds up heat in the engine very rapidly. All that energy of a truck slowing down has to go somewhere, if its not the service brakes it's the engine brake. So with the jake set to maximum the engine will absorb the absolute maximum amount of energy from the truck it can, that turns into heat, which goes into the radiator.

Secondary to that is the fact the fan draws a fair bit of hp itself

Of course if the fan is kicking the moment you start braking something obviously isn't set up right, it should only really come on in a downhill situation or a really heavy load coming off the highway.

 

How do you figure engine braking produces excessive heat, there is no fuel being burnt. The engine is just acting like an air compressor sure it will produce some heat from compression but not nearly the amount produced pulling a load. It is strickly to aid in braking.