Any harm in engine braking?

[Jeep Junkie]

Guys, offroad I always drive downhill in 4Lo and 2nd or 3rd gear. But these days even in town I engine brake in 2Hi and 2nd or 3rd gear when going downhill. Any harm in doing that specially when engine screams to 4000 or 5000 rpm? When I use my brakes it feels like they get stressed by my 37" MT's. So I want to make my brakes last long.
Thank you!

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[bd100]

While towing I engine brake a lot down mountainsides. Hope it doesn't hurt much. But it's great having cold brakes all the way down, knowing you can stop at any time.

Once came across an RV getting its front brakes redone in a campground. Hope they learned their lesson. And those truck escape ramps do sometimes get used.

Hopefully someone here can tell us what happens to the engine from a technical point of view. I suspect engine oil gets sucked out faster, for example. Check the oil levels more often in the mountains!

 

[Guv]

It does put a reverse loading on the bottom end bearings. Also 4,000-5,000 rpm can create very high intake manifold vacuum with the throttle closed possibly causing higher oil consumption. This could come from the valve stem seals, PCV circuit or even the piston rings. In the end you have to ask yourself, what’s more important frequent brake work or possibly shortening your engines life span.
Edit: I had a 2006 GTO with a manual. I received a letter from GM informing me to frequently monitor my engines oil level if I drove the car aggressively and used the engine for braking often. I was fortunate and never had an oil consumption problems but obviously they thought it was a concern.

 

[4Lo2Yolo]

I used to work with a mechanic who would swear he could tell that I was downshifting and engine breaking my work vehicle. He swore that it would put more upward load on the the rear journals of the cam bearings and that it caused increased and abnormal bearing wear. I have absolutely no idea if he was right or not, or if it was a specific engine, but I do know he was an excellent wrench.

 

[Guv]

I used to work with a mechanic who would swear he could tell that I was downshifting and engine breaking my work vehicle. He swore that it would put more upward load on the the rear journals of the cam bearings and that it caused increased and abnormal bearing wear. I have absolutely no idea if he was right or not, or if it was a specific engine, but I do know he was an excellent wrench.

It actually increases the wear on the crank bearings. Maybe he said crank instead of cam, time has a way of doing that.

 

[Waldeck]

I use the engine as a brake all the time but not on high RPM's. I slow down over a good distance using all the gears, I very much doubt I cause any extra wear to the engine.

 

[etoften]

Anyone that has ever driven hwy 250 between snowshoe wv and stauton va can testify toi the need for lower gears going down the mountain. 25 years ago there was a old man with a garage at the bottom of mountain turnpike. Forget the name of the town. He made a living off of people who warped thier brake rotors on the way down. Now I wouldn't do it on every little hill. But posted grades and long descents??? You bet. I wouldnt let it get to 5000 rpm though. Find the gear that holds you in the 3500 to 4000 range and use brakes as needed.

 

[Billy Bones]

Guys, offroad I always drive downhill in 4Lo and 2nd or 3rd gear. But these days even in town I engine brake in 2Hi and 2nd or 3rd gear when going downhill. Any harm in doing that specially when engine screams to 4000 or 5000 rpm? When I use my brakes it feels like they get stressed by my 37" MT's. So I want to make my brakes last long.
Thank you!

I think both engine braking and using the brakes work well together, without overusing one or the other can enhance safety and performance and prolong the life of the brakes while keeping heat down. The engine is tough enough to take it and the 8 speed transmission is one of the best in the industry so in my opinion it’s all good.

 

[Pape]

That is a lot of RPM for engine breaking, maybe use a little the break to keep it a lower rpm.
Funny as the automatic version do some engine breaking to a certain degree.
Hybrid are doing it a lot (regenerative), my e-torq really enjoy going down hill to a degree that I need one heck of incline to not loose speed while not even touching the break.

 

[AndySpill]

I'm getting the sense that engine braking in moderation, particularly when it supplements conventional brakes, is fine.

Is it not true that the cruise control will attempt to slow the vehicle down to speeds at which it's set if a hill is encountered by itself downshifting?

 

[Jeep Junkie]

Guys, I will make a video and post it here to show you guys what rpm engine braking I do in town. Seattle hills are nuts.

 

[Ramboy]

Guys, offroad I always drive downhill in 4Lo and 2nd or 3rd gear. But these days even in town I engine brake in 2Hi and 2nd or 3rd gear when going downhill. Any harm in doing that specially when engine screams to 4000 or 5000 rpm? When I use my brakes it feels like they get stressed by my 37" MT's. So I want to make my brakes last long.
Thank you!

In my experience traveling down Pikes Peak highway a couple of times with my 2.0 turbo Rubi, while using lower gears and tapping brakes where needed kept the vehicle in control. The guy at the brake check station said my brakes were in great shape, and another key point is to keep quality oil in the engine especially for the turbos. I use Amsoil. Just my $.02 worth.

 

[Jeep Junkie]

In my experience traveling down Pikes Peak highway a couple of times with my 2.0 turbo Rubi, while using lower gears and tapping brakes where needed kept the vehicle in control. The guy at the brake check station said my brakes were in great shape, and another key point is to keep quality oil in the engine especially for the turbos. I use Amsoil. Just my $.02 worth.

Thanks. I use Pennzoil Ultra Platinum on steriods AKA Pennzoil Platinum Euro 0w40

 

[Opus]

I learned that lesson the hard way years ago driving my mother's mini-van to take her and the family to her sister's wedding in Virginia. I had never driven through mountains before and ended up completely cooking the brake pads on that poor van. Years later I nearly did the same thing on our trip to Yellowstone and the Tetons coming down the mountain pass into Jackson Hole. Finally, I got smart and learned how to use engine braking. I live in Flatlandia and use it only occasionally, so I'm not worried about putting too much strain on the transmission or bearings.

 

[2nd 392]

I think both engine braking and using the brakes work well together, without overusing one or the other can enhance safety and performance and prolong the life of the brakes while keeping heat down. The engine is tough enough to take it and the 8 speed transmission is one of the best in the industry so in my opinion it’s all good.

This, use together so you don’t over stress either. As my mechanic father told a young down shifting kid “brakes are cheap.” . As a trucker who’s life was likely saved by a Jake Brake when the new “anti skid” brakes on a new trailer failed at the top of the old Pacheco Pass- F’ the Cummins, tach buried. … moderation and common sense work if used as needed.

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