A long time ago, in a book whose title I don’t remember, a character said, “but engine parts are more expensive than brake parts”. That has always stuck with me, even as I glide to a stop with almost no braking.
As an avid engine braker who lives in a hilly area and drives in the foothills/mountains often, I figure that at the relatively inconsequential loads and speeds my passenger vehicles operate under, I'm simply leveraging the engine's already constant state of wear while preserving my brakes for a moment when I may need their optimal stopping performance.
Very true - but I drive cars until they die - and have never had a car issue because of engine braking - it is usually another part of the car that goes before whatever damage I am adding to the engine, becomes an issue. So engine brake away!
True, however that statement sort of makes the assumption that engine braking is the same ablative system as friction braking. with the same wear characteristics.
I have to admit I don't know the exact wear characteristics of an IC engine in breaking operation but I don't think it is any different/more than it's normal running wear.
They are certainly in any way identical, but to engine break, you usually need to switch into a lower gear (or a couple gears lower), which means that the clutch needs to reattach while the engine is rolling at a higher rpm than the gearbox can handle in that gear. Every downshift will do another "reattachment" through the clutch.
Which means that there will be some friction braking before internal engine resistance "takes over". Now, while both brake pads and clutches use "similar" material, it's not the same, and the cost is not the same (clutches are usually more expensive in modern cars).