Engine Braking vs Brake Pad Costs

In my 6MT, I switch between engine-braking, regular braking, and a mixture of the two.

Recently, I started thinking about whether engine-braking combined with regular braking OR regular braking-only costed more in the long-term.

Can anyone speak on the wear of engine internals from reasonable amounts of engine-braking? (like the head gasket)

Anyone want to do the rough math and determine which would cost more overall?
- Only regular braking, and the costs of replacing brake pads more frequently over X miles.
- Engine-braking combined with regular braking over the same X amount of miles.

(for the sake of simple math, let's say we're never engine-braking above 4k RPM in any given gear)

 

Seems to me that engine braking would put no more stress on the engine than accelerating would, possibly less.

 

I think you're overthinking it; engine wear is virtually nonexistent. The only real difference is the wear on the two friction surfaces. If you're going down a long grade, engine braking will always win from a cost perspective, if you're constantly needing to stab the brakes due to traffic or curves/corners, then the brakes will typically always win from a cost perspective. For everything else it is a judgement call.

With the above said, I frequently employ engine braking and have driven vehicles well beyond the 200,000 mile mark and never experienced any additional maintenance costs or clutch replacements.

 

Are we just going to ignore the piston rings? They're not designed for engine braking like a diesel

 

I think if the engine braking rpm don't go crazy high for extended periods, it should be ok. I use my truck with engine braking occasionally when towing going down hills. I try not to exceed 3500 rpm.

 

Brakes are cheaper than clutches.

 

Engine braking is just using the momentum of your vehicle to compress air inside the motor. No it will not increase wear on the clutch or piston rings... Engine is still being lubricated as normal

 

Front pads are cheap and can be replaced on a Saturday afternoon. The clutch…. Not so much. Drove multiple vehicles with a manual and other than the piece of shit 83 S10 I never had to replace a clutch assembly. But I can replace front pads blindfolded.

 

Sorry, diesel engine braking is an entirely different thing. For gasoline engines the rings will not suffer any wear, at all.

 

Engine is fine but clutch wear increases with downshifting. Rather do a break job a bit early than a clutch job.

 

The thing is, once the clutch is engaged, there is no clutch wear, so if you are say, driving down from Toms Place to Bishop on US-395, you might drop a gear or two at the top and then leave it there, if you stay in top gear and use the brakes, you have something like 20+ minutes of continuous brake usage/wear.

 

I have a 5 speed 2.7 and pride myself on how little I can touch the brakes...
Made it from 154,000 to 240,000 on one set of pads...And only had to change them because I wore them out hard braking in reverse to disengage the rear brake cable...and the Caliper seized so...but On a manual transmission you can get 100K on a set of pads if you downshift.
I love the paddle shifters on my wifes subaru..it drives her crazy when I downshift to decelerate but that car rips through brakes...

 

The amount of wear on a clutch downshifting is so minimal compared to accelerating from zero. One start from a red light probably equals 1000 downshifts.

113k on my manual '21. Original pads and clutch.

 

Solid Friday post

 

Adding two cents, provided you rev-match your gears and don't rev over redline I don't see any significant wear difference. If it could be worked out I would be curious to have a concrete answer however, calculating a cost/savings ratio would be difficult because there are alot of factors that play a role in that calculation that I don't feel could be eliminated outside of a controlled lab environment. Yes it causes more wear to down shift to 5500 RPM than to use your brakes but, I doubt it would ever be noticed over the life of the vehicle. Maybe the pilot and/or throwout bearing would be found to fail prior to the clutch friction material.

I am personally a supporter of downshifting when you can so that you're in the correct gear in case you need to quickly transition from losing speed to gaining speed and, to take a load off your brakes. Especially if you're loaded up via towing or hauling. As stated above if you need to slam on the brakes then slam on the brakes but, if you're coming down a long hill and/or can see your stop from a mile away and you're not gonna hinder traffic then I feel you should downshift as you approach.

All in all I would say the safety benefits equal an overall benefit to downshifting as even newer automatics downshift automatically as you slow down and apply the brakes. That doesn't really answer your question though as you asked about the mechanical aspects.

 

That is true, but you aren't going to do any damage to the engine or clutch by downshifting and letting the engine hold you back as long as it's done right. Even done wrong it will take years and tens of thousands of miles for the engine, transmission or clutch to cause problems. Overusing your brakes can cause them to fail and send you off the road in under 10 miles. You can tell there are a lot of flat landers here. Anyone who lives or regularly drives in mountains knows how to do this.

It doesn't matter if it's an automatic or manual. You either downshift BEFORE your speed is excessive or use your brakes to slow down then downshift. And it doesn't mean you never use your brakes; you just use them less. If engine rpms get uncomfortably high, then use some brake to slow it down.

 

Downshifting is a good thing. I use S-mode when I off-road (not as much as others, but ...). Brakes tend to cause skidding. On dry pavement, need much speed loss. On gravel-covered dirt roads, braking can send you out of control at the worst possible time. Thus 4Lo is just 4Hi with engine-speed-reduction gearing. In snow and ice brakes can be fatal if applied too quickly.

Do not redline the lower gears, but save the brakes from over-heating until you need them or can safely brake.

 

I'll tell you one thing I do. When I see a red light up ahead I take my foot off the gas pedal, while other idiots are racing up to the red light, the slamming their brakes.

More times than not, I cruise by them as the light turns green and I'm still coasting and they now have the hit the gas to get going up to speed again. Next light, same thing.

And I'm by no means a slow driver, I'm a somewhat smart driver.....