Does racing the engine burn more gas?

I often try to gear down when slowing down so I don't have to apply so much brake. I have wondered this for years and now only decide to ask...but does gearing down and racing the engine burn more gas? I would think not as I am not giving the engine gas.

 

our engines use engine braking so when u downshift it actually will shut down injectors... some say you will cause more wear on the engine. Not sure what u mean by racing the engine but whenever i floor it on the highway or something like that i will notice lower mpgs on that tank

 

I think what he means by "racing" the engine is that when you downshift, the engine "races" to higher RPM's. Correct?

 

I think you answered your own question.

Does it save on gas to 'gear down' instead of braking? Not enough to notice it in your wallet.

 

i will say one more thing about engine braking... when driving through the mountains of West VA i got better gas mileage than during normal driving, which doesnt include much traffic, i would down shift my truck into 3rd and 4th, AUto, and coast down the mountains... saved my brakes and saved gas too

 

Yes, that is correct. I should have said..."gearing down thereby racing the engine". I guess the proper term is engine breaking.

Thanks for the comments.

 

I use engine braking all the time. i love it.

 

I have tried to answer this question myself since I put my ultra gauge in. Its tough to tell since there is a slight delay in the gauge. if there is an increase in MPG, its not noticeable on the gauge.

 

Makes kinda miss my manual trans.

 

brake pads cost less than a clutch/transmission...

 

I always try and coast up to stop signs and red lights whenever I can. With the scanguage it will read 9999 when coasting, meaning you are getting infinite mpg since it shuts down the injectors. I gained about 2-3 mpg per tank just doing this and trying to keep the rpms below or as close to 2k as possible.

 

Oh Hell..here comes the ....I made that comment in the 4cyl thread about the manual transmission and it got everyone bent out of shape.

 

i agree with this 100%. now on the race track, all bets are off. i am a doubleclutching/heel&toeing fool!! (not so good for mpg)

 

yes, you burn more gas. you're at a higher rpm when you do that.

 

Glad I have one, no SUA danger FTW.

My thoughts exactly.


Your ujoints won't love you long time doing engine braking like they might if you use the brakes to brake. Yeah, I know, there is a time and place for engine braking but it isn't all the time and isn't anything to do to save gas, you can do better controlling driving habits other ways. I personally would be babying an auto more than a manual, not abusing more. Engine braking not for much more than controlling descents offroad or on steep paved descents IMO. Go for it tho, they're your trucks, have fun.

 

incorrect, b/c our trucks turn off injectors when no gas is being applied, so slowing down the truck with the engine actually uses less gas

 

how? how does great manual driving skills make the forces inside your tranny go away? the clutch still sees added friction..all the gears will have shear, u-joints.. i dont get it.

so your brake pads wear out fast..

 

How do you turn off injectors and the motor stays running with no gas being sprayed into the cylinders? Does it also shut off coils to save wear on the spark plugs?

 

Maybe, but so long as you aren't throwing it into the red each time you're fine. The truck won't let you put it in a position to damage it.

I engine brake all the time via down shifting my auto.

It pretty much always tosses the tach into the 3000-3500 range.

Hard acceleration puts more stress on the u-joints and tranny than my mild engine braking does.

Besides, my auto has the V8 A750F tranny in it so it's already upgraded.

 

Engine turning is one thing but the motor cannot run if it isn't getting gas/air/and spark. It will not "run" on less than all 3 of those.