Does down-shifting use more fuel?

My understanding is that, no you dont use more fuel, and no it will not damage the engine due to cooling to fast. the fuel is cutoff to injectors when the engine brakes are applied ( exhaust valves are held shut by small soliniod pistons that indirectly push down on the exhaust valves) as for cooling the engine too quickly it is more so that the coolant cools a little bit quicker than if you were to turn the radiator fan onto manual, the oil and engine block and head would not cool down as quick as the coolant does, so damage to the engine would not be possible.

 

Robert --

Do you mean using Jakes? That slows engine speed and will slow the vehicle (unlessyou'regoin'downhill
andyou'reloadedheavy
andthejakeswon'tholdit
thenyoukissyourkeistergoodbye)

In full-stage Jake use, fuel is cut off and returned to the fuel tanks.

No.

Hey! Where are those potato chip pics?

 

When the guy yells "Look out below!" he's not fooling around. Okay, the ramps rely on 1) steepness (=pull of gravity) to slow the rig and 2) deep, loose gravel to arrest it. This can be hard on the truck. But the ramps get the truck off the highway. Running along the median wouldn't, and you'd have pieces of the truck flying off, not good for others on the road. Possibility of fire, too, if you shred the left-hand fuel tank on the barrier.

I'm thinking of the ramp just west of the Eisenhower tunnel. That is one steep sucker. I remember a JB Hunt driver who went into it. I was headed east and I could hear him all the way from Frisco on the CB--sounded like he was in a mild case of shock. He'd gone almost to the top of the ramp (I saw this when I passed the ramp) and he was saying he wanted to back all the way down, but couldn't get his air pressure up to release the brakes. I think he tore out an air line or two in the gravel -- he'd sunk to the axles; he wasn't going anywhere. An officer was climbing--slowly--up the ramp. When I drove by, he still had a long way to go.

I do believe it's big bucks in most states when you use one of those ramps. There's a re-grooming fee (they regrade the gravel), wrecker fee, maybe a fine. And then there's the new seat. IIRC, Oregon didn't use to fine drivers. California probably does. And they always say, "Lemme see your log book."

Post pics of the destruction when the bag blows! Or film it and put it on YouTube.

 

Ok, first off i downshift when slowing down, coming to red light etc. i don't know why i do this, i just do.

But thank you for asking this question because now i'm questioning why i do this.

i think the only reason to downshift is to help maintain control of the vehicle if you're going down a steep hill and let's say your brakes fade away. Then you've got some engine compression to help slow you down. OR to help maintain a speed so that your brakes don't fade.

Other than that i think using the engine to help slow you down doesn't make sense----this is what the brakes are for and brakes are relatively cheap and easy to change. Especially when compared to an engine/clutch.

 

i sure hope these are joke answers--they are right?--like you guys arnt serious are you?--you are starting to scare me

 

If you've ever ran out of brakes before you save your brakes for when you need them! The engine brake is part of the braking system

 

I believe,THEY BELIEVE it is the way you do it
Scary bunch running loose these days,I tell ya