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Save brakes by using transmission

I live in San Francisco, which is very hilly. I drive a Mercedes-Benz SUV. Can I save my brakes by down shifting my automatic transmission to level 4 when going down hills? I was told this is why you have different levels on your transmission. But I was also told by someone else that using my transmission to save my brakes is more costly.



Mercedes-Benz need brake & rotor replacement more than any other car I’ve ever owned. Please advise.



Thank you.

If you think the brakes were expensive, wait until you buy the transmission…

I agree, tranny shouldn’t be used for braking down those short steep SF hills. Longer ones, sure. Just consider those brake jobs a part of the price of living in the city.

Brakes wear out because of use. In places where there is a lot of hills, like San Francisco, brakes get a lot of use. You could move to Wichita where they don’t have to use their brakes as much but then you would will miss out on the hills and the Golden Gate bridge. Use the brakes and save the transmission.

You do need to downshift for long mountain passes, but that’s more of an issue of preventing the brakes from overheating on long highway-speed downgrades. Just going down a short urban hill, no matter how steep, won’t tax the brakes sufficiently to justify downshifting. In practice, downshifting on short steep hills won’t really reduce brake wear that much.

Also, your engine is providing the braking force when you do this (not the transmission) and unless futzing with the gearshift causes you to crash or something, it’s not going to damage anything.

Every-time an automatic transmission shifts, it wears…The manufacturer can tell you exactly how many times it will shift before it shifts no more…It’s like the ticking of a clock…

@Caddyman: “Every-time an automatic transmission shifts, it wears…”

Yes, every time a machine does something, it wears.

“The manufacturer can tell you exactly how many times it will shift before it shifts no more…It’s like the ticking of a clock…”

Oh, really? Care to explain the math behind that? Sounds like nonsense to me.