Diesel Engine Brakes

[powermad]

If it's a diesel with EGR then it has a potato brake of some sort already.
Turbo's with a VGT close off the vanes creating back pressure, which is needed to drive the EGR.
Non VGT turbo's will have an actuated flap to choke off the exhaust and create back pressure.
Which also works well for engine braking.

Volvo engines up to the newer D13 used a potato (Exhaust Pressure Governor) and compression brake (Volvo Compression Brake) The EPG was then used to drive the EGR when that came out.
Now they just use a VGT to drive the EGR and is the 1st stage of engine braking.
The compound turbo D13 uses a pair of regular turbos with a potato.

PACCAR uses a potato, VGT turbo and PAC brakes.

 

[Nosferatu]

All I know, when I downshift to 3rd gear and lock out 4,5 & 6, I can cruise down 4th of July and Lookout passes in Idaho at 60-65 MPH towing upwards of 14,000lbs without touching the gas or brake at all. At least until some jackwad in a minivan cuts in front of me and slams on their brakes.

 

[Nwcid]

All I know, when I downshift to 3rd gear and lock out 4,5 & 6, I can cruise down 4th of July and Lookout passes in Idaho at 60-65 MPH towing upwards of 14,000lbs without touching the gas or brake at all. At least until some jackwad in a minivan cuts in front of me and slams on their brakes.

I have done the same in my duramax. Just use the tow/haul, engage the exhaust brake and set the cruise speed I want to maintain. My RV is 17,000 lbs. I do the same on the Pendleton grade.

 

[outdoorsman]

If you have a diesel pickup with a VGT Turbo then it is best to keep the exhaust brake on all the time. Using the exhaust brake all the time helps to keep the sliding ring in the turbo from getting sticky. It will not hurt the engine but will help prolong brake life and is actually better on the transmission.

 

[Ura-Ki]

Best sounding Jakes of all time, the Legendary Detroit Diesel 12V71 twin turbo, twin supercharged on a full rack Canadian Style with Water cooled brakes!

View: https://youtube.com/shorts/dr-GsKBe_P4?si=yUCJrVCbUaT1faQ8

 

[boattail]

SO, there are Three kinds of "Diesel Brakes" and the vast majority of your pickups use only ONE!
Jake Brakes ( an Actual Exhaust Brake BTW) , that's ONLY found on the large diesel engines, usually 10L and up ( Yea, some small DDEC's have Um) so don't worry about those, these are the only mechanical Exhaust Brake out there, a Clessy Cummins Invention, he failed to patent and Detroit Diesel jumped on it and filed the patent and called it,.....................The JAKE BRAKE!
Down Tube Brakes, ( Cummins Patent PAC-Brake, Often incorrectly called "Exhaust Brakes") this is by far and away the most common "Brake" system your going to find on small diesel engines, it's literally an exhaust throttle, in that it closes off the exhaust after the turbo to provide the back pressure that gas engines are known for, that nice hold back your used to.
Magneto Brakes ( Called Brake Savers), this has been around for over 50 years, on some engines it works, some they haven't figured them out, the big users are CAT and Volvo, and some of the older Cummins KT series Engines especially the Big KTA-440 and even bigger KTA-600 engines, it's literally an electro magnetic flywheel brake, and when it works, it REALLY works. My Big CAT 3408 has BOTH the Brake Saver and a full rack of JAKE'S and you can only run One system unless there is a big load behind it, otherwise things down stream get REAL EXPENSIVE!

So, your Pickup uses a Down Tube Throttle, that's it, and there is Almost no issue with running around with it "ON" other then some temperature issues you should watch for, but there is NO mechanical load on the engine it's self, only the valve and it's moving parts and controls, So run it how ever you wish, there is NO disadvantage to running it constantly, it only works when you let off the throttle and once the RPM's drop to near idle, the valve opens and the engine continues to run as normal!
The Biggest issues these systems have is the valves locking up, ether because of too much heat, or loss of lubrication in the oil-lite bushings, and the seals tend to fail over time, with Cummins, it's an easy repair, and the valves are cheap enough to replace, ford and GM, not so much, but still almost reasonable, even Isuzu runs this system, and are one of the best there is, for engines that don't have one, use the Isuzu valve, you'll thank me later!

Jake brakes are not exhaust brakes. Jake's, through manipulation of the valves try to make the engine run backwards. If on ice you can actually get the wheels to turn backwards as I have done it. .

 

[powermad]

Most compression brakes are part of the exhaust rocker now, less parts.
I'm putting a PACCAR together today and it lost a piston in each rocker shaft assy, if they fall out it's broke.


Only newer one I know of that still uses push tubes, cam comes out the back so you pull the engine.

 

[Unka-Boo]

Most compression brakes are part of the exhaust rocker now, less parts.
I'm putting a PACCAR together today and it lost a piston in each rocker shaft assy, if they fall out it's broke.
View attachment 1862203

Only newer one I know of that still uses push tubes, cam comes out the back so you pull the engine.View attachment 1862205

MX13?

 

[powermad]

Yep, the mighty MX..
Eat a cam bad enough and get a short block.
Leaking head gasket and a bad cam gets you a long block. 7 year 700,000 mile coverage.
No one has ever seen one get overhauled.
If main bearings do get done it's the lower shells only.
You can not roll the uppers in, the crank has to be out.
Not like it's million miler anyway so...

 

[powermad]

Just a cam, oil pump, lower mains and oil cooler.


Cat and their no EGR was ridiculous, last year of the Cat, C13


Leaking exhaust manifold? see ya next week.

 

[Unka-Boo]

Just a cam, oil pump, lower mains and oil cooler.
View attachment 1862261

Cat and their no EGR was ridiculous, last year of the Cat, C13
View attachment 1862262

Leaking exhaust manifold? see ya next week.
View attachment 1862263
View attachment 1862264

Been a parts guy for 30 years...started in automotive and rolled to heavy trucks...was at Freightliner for 15 years, at KW now. Grandpa was at KW for 44 years ( Roberts Motors ) he probably would have disowned me if he knew I was at FTL
Done back counter the whole time, so pretty familiar with all that...still learnin the MXs, have to scrub the Detroit outta my brain . At least Cummins and Cat are the same accross the board.

 

[TTSX]

Sounds like everyone has a different opinion on what an exhaust brake is. How neat, it's like watching 9 vs 45 but in armchair mechanic

 

[Nosferatu]

Sounds like everyone has a different opinion on what an exhaust brake is. How neat, it's like watching 9 vs 45 but in armchair mechanic

I thought it was those things people wore on their faces during Covid.

 

[TTSX]

I thought it was one of those things people wore on their faces during Covid.

Some people still should. Their intake and exhaust smell the same, I'd like them to equip a "brake"