Engine Brake

Has anyone heard of engine brakes? Yesterday was the first time I had heard of it. I have not ever towed before and I will start to soon since I bought a travel trailer. So now I am going to learn. I have a 2007 Tundra SR5 Double cab and a 5.7 engine. And was wondering if my Tundra had that type system. thx Novice.

 

An engine brake is more of a Jake Brake on semi-trucks. It's an additional valve that releases the compression within the cylinders...that loud sound trucks make sometimes. But what pickup trucks sometimes have is the tow/haul feature which uses both your transmission and engine to brake on hills instead of using your regular brakes.

 

Is this different than when you have the cruise control on and the p/u picks up speed the engine slows down to the set speed on the c.c.? If I had that there would be a switch or something? thx

 

No CC is simply adjusting your throttle. If going down hill with CC the vehicle will speed up due to gravity and the vehicle will back off from the throttle automatically. However at some point there is no more throtle to back off so applying the brakes will be necessary. All these systems do similar things but are for totally different purposes.

 

I thought that would have been to easy. Thanks.

 

Engine brakes are for diesel engines. Gasoline engines naturally brake themselves due to the throttle butterfly.

 

Thx
I spent a few years living on 35th Ave and Tonto, close to Buckeye Rd. Miss the valley.

 

There are transmission retarders too. They restrict fluid flow in the transmission to cause a braking action.

I've noticed that in my truck, if I'm descending the pass with the Cruise Control off, the truck will pretty much run away like you describe. But, descending the same grade with the Cruise Control on, the transmission will automatically downshift when I reach approximately ten MPH over what the cruise is set. This raises the RPMs and accentuates the engine braking effect slowing the truck. This is without using the Tow/Haul button which seems to be somewhat more aggressive, particularly when you tap the brake.

Don't the folks over in the UK rate engines in Brake Horse Power (bhp)? I thought that I read this is the braking effect of the engine when the throttle is closed after revving it to red line. This may have been applied to motorcycles. I don't know if the two measures, theirs and ours, give similar numbers.