Downside of using exhaust brake.

[lmills]

I was talking to my brother-in-law the other night about the trranny upgrade I am doing. When I told him they recommended the hardened shaft if I had condsidered and exhaust brake, he told me something I am not too familiar with. He says that running exhaust brakes causes increased wear on camshaft lobes. Is there any truth to it? He says he knows of people personally that have had that exact problem.



Is he passing the plate of buffalo chips? I think he is nuts.

 

[Sixpack]

If you install the Jacobs, Cummins and DC have no issues with warrantee coverage. As for your question I'm sure others will chime in as to the wear issue. Phil

 

[Joe G.]

Buffalo chips for sure. I've been using mine for over 170K miles.

 

[Camara]

If I remember right Mack trucks had a camshaft problem in the late 80's. The exhaust brake we use is after the turbo and does not touch the cam. The other style Jake is mounted on top of the engine and directly connected to the valve train. The Cams Mack used had a "soft " coating and they wore prematurely. The guys I work for had a 64 Autocar with a 220 Cummins in it and that engine was still running until last year. The cam finally wore out after 38 years. My trucks had jake brakes and went 500,000 miles with no abnormal wear. :-{}

 

[illflem]

I think your bro in law is thinking of an engine or Jake brake. I've never heard of increased cam wear from one but guess it's possible since the cam is an integral part of an engine brake. How a engine brake works- https://store.howstuffworks.com/howstuffworks/question134.htm

 

[dresslered]

Only thing I've noticed is a little extra wear on the rear tires but that sure beats wear on the brakes (I drive unloaded most of the time so I can actually get my rears to hop at times).

 

[Deezul1]

Our exhaust brakes work after the turbo in the exhaust system and have no connection to the cam shaft. There is no difference in using an exhaust brake on a Diesel/Dodge than there is in a gasser when down shifting and using compression to slow down and I hev never heard of cam wear on a gasser from downshifting.

 

[lmills]

I thought he was nuts. I couldn't put a solid connection between the increased back pressure in the exhaust causing the cam lobes to wear off. Oh well, I feel a little better now.

 

[CumminsPower98]

What I have long wondered about is if the #60 valve springs make any noticeable wear difference on the cam that people install when doing an e-brake or a 4k GSK. It is logical that it would increase the wear rate some but probably not enough to notice. Any ideas? Maybe some oil samples trends? - Mark -

 

[Lnwing]

A neighbor bought an old dump truck that had a 3408 Caterpillar engine equipped with an exhaust brake (not engine or Jake brake). It was worn out, and sucked gallons of oil per day.



A well-respected shop/mechanic checked it out, and said that the valve guides, especially, were shot, and that exhaust brake use "sucks the oil off the valves" and wears the guides prematurely.



Has anyone else ever heard of this?



Lynn

 

[lmills]

Well, I would think that it would take a vacuum to pull the oil out. The exhaust brake is actually going to increase back pressure.

 

[Joe G.]

Originally posted by Lnwing



A well-respected shop/mechanic checked it out, and said that the valve guides, especially, were shot, and that exhaust brake use "sucks the oil off the valves" and wears the guides prematurely.

Lynn

This kind of stuff from "well-respected" hazzards in the garage is why I do as much of the work on my truck as I possibly can.

 

[Doubleclutch]

ILLFLEM- do you ever sleep? Nice explanation on how an engine brake works. Navistar did some R&D on a cam-less engine, probably using either solenoids or hydraulic operated valves to pass air into/ out of the cylinders. You would think that in a cam-less engine, a simple controller modification would provide superior "exhaust" braking. Of course that would enable another aftermarket industry... providing a good intake muffler... I guess we stay tuned.

Greg