How to engage your Exhaust Brake on a Duramax!!! 

OMG it is Brake not Break. Were you paying attention in school that day?

​@Edward Pate it's* now stop being a loser about spelling. It's RU-vid

It works in those gears just ineffective down hill.

We are testing out the factory algorithms. Ultimately had the same behavior as if I manually selected the gear. Which is impressive!

Correct the exhaust brake does work at lower RPM. When the exhaust brake is active your generating negative torque. You need the negative torque then multiplied by lower gear ratios to be effective. That negative torque being multiplied is what slows the vehicle are larger grades.

It's the same system on a smaller scale as the 6.7 Cummins, 6.6 duramax and 6.7 powerstroke. All use VGT for exhaust brake. No consumer level truck has a Jake brake.

It's not about slowing, it's downhill control so speed doesn't rise. Only works in tow haul.

I got a 2.8 and mine kicks in all the time, sometimes more than others, as stated it works with Tow Haul Mode only. My comes on when I tap or hold the brakes when I’m in 2nd gear or higher

The vanes being closed is. And diesel can't compression brake 😉

I don't understand.

Wtf is a Cummings? I've heard of a cummins

@@benjaminturpin2749 I heard it’s what guys do on your face, and I think they put them in generators.

@@benjaminturpin2749 stepped right into that didn’t ya🤪

Cummins not Cummings!

Exhaust brake

@@duramaxadventures5832 Yeah, don't want anything to break! Just brake!

@@edwardpate6128 can't just ride the brakes when towing, they will stop working completely due to heat.

It's the exhaust brake on the LM2, it needs RPM to generate negative HP to control the load. The cruise uses the brake pads to slow the truck, it also has similar behavior, however it waits until 10-15 mph over you selected speed and doesn't pull it back down to the set speed.

You need RPM to generate the back pressures to slow.

@@duramaxadventures5832 All I have to say is go drive a newer Duramax 2500Hd and use the exhaust brake. Then go drive a Ram 2500 diesel and use the exhaust brake. There is an absolute world of a difference between the 2. The Ram jake brake can be switched to auto or full on. The Duramax can't. And when that Ram jake brake is set to full on boy is it a thing of beauty. You barely have to touch the brakes even when you are towing. It stays on until around 10mph or so too. Ram jake brake acts more like what big rig trucks have on them. Just wish GM would do the same.

@@richr909 Jake brakes and exhaust brakes are not the same thing. There's a really good donut media video on it.

@@richr909 Facts.

@@richr909 two things 1. None of these are jake brakes, they’re exhaust turbo brakes, they work by opening and closing vanes in the tubro. 2.Rams mode works by itself, in tow haul, and in manual mode. The GM one is connected to tow haul mode, which is why it wants to downshift to engage it

its actually applying back pressure to the exhaust while also adding boost to the intake to slow the pistons. That's what makes it such a capable tow rig!

@@duramaxadventures5832 Lol

@@2K9sya he must not be familiar with the LM2

@@duramaxadventures5832 The 3.0 is very different.

Like 1/4. Yes in tow haul

Brake, not Break!

Exhaust brake =/= engine brake. 😉😉

Lightly apply the brake to where they are barely activated.

@@duramaxadventures5832 thank you

Extremely light input. Not enough to actually put pressure on the brakes. Just enough to activate your rear brake light switch.

@mixedgrid is correct, here I am actually clamping the pads but the load is heavy enough its not slowing down. Similar pressure to creeping at a stop light would probably be a good reference.

you CAN but it needs RPM to really help. basically on GM teh ECM does its own thing. all you are really doing setting teh exhaust brake to on is allowing the computer to use it. in icy conditions and slippery conditions it could be dangerous, but if TCS detects slip it disengages the exhaust brake. there is no risk using an OEM exhaust brake on longevity (aftermarket depends on many design factors) . but it doesn't have many benefits when unloaded in teh city. highway yes it could help you use less brakes.

Yes it is, it closes the VGT down to generate back pressure. Just like the 6.7 Cummins, 6.7 Powerstroke, and 6.6 Duramax. All we are adding witn "drag the brake" is engaging the grade shifting logic.

Anytime you are off throttle in tow haul the exhaust brake is active generating back pressure to increase control

@@duramaxadventures5832 No Sir, I’ve owned Chevrolet’s and Fords, both diesel and gas) and currently in a Ram Cummins. There’s nothing to compare regarding the Cummins exhaust break and they have a dash screen showing both turbo boost and exhaust break real time hp… very different from what you’re showing with tow haul engine break via rpm. The VGT system is a patented Cummins design that controls boost pressure much more effectively. The desired boost pressure can be regulated for various engine loads creating more efficiency. The Cummins Holset design uses a set of guide vanes that controls exhaust gas through the turbine. The difference between the Cummins and conventional design is the standard design pivots the vanes to get variations in nozzle areas while the Cummins VGT vanes don't pivot but slide on it's axis. The VGT raises the exhaust turbine efficiency because of the accurate angles it can achieve. The sliding nozzle ring design can easily increase exhaust gas flow onto the turbine wheel. As the geometry changes inside the turbo the boost is increased as the nozzle is closed down. The increased exhaust pressure speeds up turbocharger speed. When the nozzle rings open boost decreases to maintain the best boost levels according to engine rpm. The variations are endless with the VGT to suit all engine loads. Other benefits include improved fuel economy, EGR emission control and assistance with regeneration of the DPF exhaust system. I am sold with the ISB diesel and we are very happy to be ordering our buses with nothing else but the ISB option planted in the IC conventional school buses.

@@2K9s You are mistaken as well. However please feel free to subscribe because I have a video actually showing what's actually occurring coming shortly. This is not engine braking by RPM alone, there is actual backpressure being produced on the engine via the turbo giving it an exhaust brake. If you disable tow haul the backpressure plummets and you race down the hill even with RPM over 4,000. And Cummins doesn't make a half ton diesel anymore.

@@duramaxadventures5832 No thanks. Nope, I’m not and I doubt the engineer’s are mistaken too. Look what you’re comparing this to above. Comparing doesn’t make sense… but you’re probably right about everything.

How else would you tow? Brakes only? Liquified pads after 2 miles. 😆

You don't have to drag it it will eventually down shift around 85. And it's an exhaust brake not an engine brake.

You are misinformed. This is direct from the 3.0 diesel supplement. "Exhaust Brake Exhaust braking is automatically activated when Tow/Haul Mode is selected. It maintains the vehicle’s speed by automatically implementing a shift pattern that uses the engine and the transmission to slow the vehicle. The system will command downshifts and use the turbocharger on the engine to reduce the vehicle’s speed when the brake is applied. The normal tow/haul shift pattern will return once the vehicle is on a low grade or when the accelerator pedal is pressed." I welcome any further information requested on the matter.

It literally says exhaust brake engaged with you hit tow haul. It pops up on screen. The big duramax has a separate button. The 3.0 turns it on automatically in tow haul mode. That being said hopefully I’m not disappointed first time I tow.