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Is engine braking harmful?

376 Views 1 Reply 2 Participants Last post by  23Molavi
This is a question for the more mechanically inclined/experienced here. It could apply to any of the newer technology engines we are seeing these days, including the Cross 2.0L....

Is it harmful to the motor or drive-train to use the engine for braking while descending long steep hills?

Of course it saves wear and tear on the brakes, and you don't want to overheat them. I was told by a mechanic many years ago when I asked him this same question, that it actually could be helpful. His reasoning was, it creates a vacuum in the upper cylinders, and that pulls a little oil up past to the compression rings, which could always use a bit of extra lubrication.

Now that was likely the case for motors in the 1980's, but I wonder about todays "loose" engines.?. I do lots of mountain driving, and it's really a must to keep from trashing the brakes in 20k miles. But is it OK on the motor?

Over reving the motor is never a good idea, but I'm talking about downshifts that take it up to a sustained 2-3k RPM.

Dave O.
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I think if your RPMs are up, then oil is circulating, the ECU will know that the throttle is closed and shut down the fuel injectors. That is my understanding.
If it was harmful, they would not make it available. Also, engine braking is a safety issue. Friend's son crashed their huge SUV due to riding the brakes and overheating them. It was an older car and I don't think they had changed the brake fluid either. They were lucky nobody was seriously injured, but the car was totalled,
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