The 2024 Duramax has got even better, pushing out more power, more torque, more towing capacity and I’ll. Tell you what I think as a diesel: mechanic. Welcome back to the channel, I’m Alex! We have this 2024 second gen l5p Duramax with us, which I’m pretty excited about. Today we are going to focus on all the engine up upgrades that GM has done to this Duramax to give it that extra power, torque and towing capabilities.
Lastly, we’ll talk about where this newer second gen Duramax engine now sits in the HD pickup truck diesel Market in future article we’ll also be doing some Towing some fuel economy testing, as well as talking about some things that I don’t like about this second gen l5p. Duramax and the truck in general so look forward to those article. The l5p Duramax platform made it to in 2017 and in my opinion it was a desperate change that GM needed previous generation Duramax the LML Duramax that ran from 2011 to 2016. It was pled with a couple critical issues and well. This l5p dermax, when it came out, did not disappoint.
It had a brand new, revamp, fueling system, new emission system, and so far I think it’s very fair to say that most owners are very satisfied. With this platform of engines, the first gen l5p was putting out 445 horsepower as well as 910 lb feet of torque perfectly adequate for the time. But in 2023 Ford went off the freaking top ropes and dropped the high output Power Stroke, putting out 500 horsepower and 1200 lb ft of torque. So as we are in this seemingly arms race between these diesel engines, um Duramax GM has responded by bumping up the power numbers in this second gen l5p. This Duramax engine is now putting out 470 horsepower, as well as 975 lb feet of torque, as well as pushing the max Towing numbers for these 2500s well above 20,000, lb all while maintaining the same engine size and configuration the first major change with the second gen Lp5 Duramax involves the high-press fuel pump.
This engine will have a peak injection pressure of 32,000 PSI. It’S about 3 ,000 PSI more than the first gen um. It does seem like they’re, going to continue to use the Denso HP4 highpressure fuel pump. I can’t confirm that, but just by looking at pictures it looks like it’s the same pump, um Denso, the HP4 pump has been used on this platform since 2017. It’S a Japanese manufacturer and so far it seems to be a very, very good upgrade over the previous cp4 highpressure fuel pump, which was a little bit disastrous.
Now, along with that cranked up high pressure fuel pump, GM has also added reinforced um high pressure fuel rails. As well as updated injectors with slightly different nozzle patterns, the reason why higher pressure Diesel Injection is advantageous is because well the higher the pressure, the more atomization that you get and you just get a cleaner burn, essentially meaning that you can use less fuel to get The same result, the reason why diesel has to be atomized, because it just doesn’t really burn that well to begin with, like it literally puts the fire out, try that with gasoline it won’t do the same thing. I can guarantee that moral of the story is that higher injection pressures just mean you can have more atomization, which means you just have a more efficient burn, leading to more power and critically less emissions. The second major upgrade for this engine involves a new piston um. Gm has gone for a much more aggressive, almost a racing style piston in these engines.
Well, we brought a piston inside this is from Detroit Diesel 15 and as Gail Banks describes very well, which I’ll link his article down below um. Basically, the reason why GM raises this cone – hopefully you guys – can see you know it’s a cone shape, but GM has raised this pretty significantly in the hopes of pushing air outwards. As this piston comes up because, as Gil Bank says, this area tends to be very lean, and so, if you can push the air outward you’re going to get a much more efficient, cleaner burn, which is going to add more power as well as reducing emission or Soot, which I think every engine manufacturer is looking to do right now. The cylinder heads on this engine will also be updated. Um.
They have revised water jackets in them, which is supposed to help with cooling heat dissipation once again, um, ideally helping with just the efficiency of the engine. This engine will also come with updated cylinder head gaskets. Gm has beefed them up and it kind of makes sense, because, while the fueling pressure has increased, there are different pistons on here, which could lead to increased combustion chamber pressures um. So I like that they’ve beefed up the cylinder head gaskets. Another new feature is well the turbocharger.
You guys can see the vgt actuator right there. This turbocharger comes with a slightly bigger turbine housing, which you can kind of see um, as well as a slightly different blade setup. It comes with one less blade on the exhaust side to ideally let more exhaust Gas Pass while still being able to maintain the same horsepower rating out of the turbo without a doubt, the biggest Improvement. Is this updated, vgt actuator GM claims that this new vgt actuator will be able to control the turbo speed much quicker. This is going to lead to increased um, throttle response that are fuel economy, lower emissions and overall, more power, a vgt or, in this case electronic variable, Dr turbo.
Essentially, what that does is it allows a turbo to act like a small turbo, as well as a large turbo. All in one package, you want to get this truck moving quickly with minimum turbo lag. You want this turbo to able to spool up very quickly. However, when you got a big load behind you and you’re already at speed going up a hill, you want to develop a lot more boost, so a vgt turbo can allow a single turbo to kind of do both very well and the quicker the actuator is, the Better throttle response you’re going to have the better performance going to have another thing that I really like to see that GM has done with this engine is improved the exhaust brake. I know for a fact when I tow with this Duramax with the load behind it.
I was really not that impressed with the exhaust breake in comparison to first of all, the power stroke, which I thought was okay in the 67 Commons, which was the best by far um. So GM has recognized that they need to improve their exhaust brake and they have done so with this engine and just kind of driving around town here it definitely does feel a little bit more aggressive, responsive than the previous l5p duramax’s. So for this engine setup, the vgt turbo actually provides the exhaust braking and well, if there’s too much exhaust back pressure, what can happen is the exhaust valves will actually start to float, and so what GM has done with this engine is they have actually stiffened up The exhaust valve springs about 20 %, stiffer meaning that this VG turbo can provide more exhaust back pressure, meaning a stronger exhaust brake, which this engine, in my opinion, really needed. Another nice increase is towing capacity. The 2023 crew cab 4×4 Duramax could tow a maximum of 18,500 lb.
This truck this configuration 4X4 Crew Cab, Kento 21,600 lb, which is over a 3,000 lb Towing increase pretty significant, if I do say so, myself and I’m really excited to get a load behind this truck and see how it handles on my Towing course. So those are the major mechanical differences between the first gen and the second gen l5p Duramax that are helping to give this engine a little bit more power. Although I can almost guarantee GM has tuned this engine differently, which probably is also helping to add a little bit more power as well, no handle a button G. I don’t like that. Bottom ends on the second gen L5.
Ps did not change at all, which is no surprise. They were already very strong. Um cast iron deep, skirted block cross bolted Mains, Forge crankshaft, Forge connecting rods, um fractured Journal caps, so basically as strong as she’s going to get and so GM probably figured. There was no need to change the bottom ends because they were already nice and beefy. These Duramaxes have always been quick engines.
In my opinion, and while this updated l5p is no exception, woo she’s got a little bit of power behind her and according to Motor Trend, this thing weighs 8,300 lb she’s a heavy beast, but it’ll go 0 to 60 M. An hour in 6.2 seconds, which again these things are not race cars, but that is pretty darn quick. I believe the Ford power stroke will do it in 6.1, because well, that power stroke is a little bit of a beast, but these Duramaxes can confirm they are still pretty quick Little Engines now.
Finally, where does this updated Duramax engine put these um GM HD trucks? In the HD truck segment, first of all, I can say that the 2024 GMC HD trucks are probably the best looking trucks in the segment at the moment. Let me know what you guys think about that uh that hot take. I do still think that Ford um takes the crown with their high output um Power, Stroke in terms of performance. The fact that you can get a high output power stroke in a 2500 is pretty incredible.
I also do like the fact that you still get a solid fun axle with the Ford Super Duties in terms of like interior and ride quality. I think GM Takes the Cake here with their 2024 HD trucks. Pretty awesome inside these things – and I I mean to be honest – I I’ve always liked the l5p Duramax. I think it was a massive upgrade over the LML and, to be honest, I think that engine really did hurt the Duramax name. Now you might be saying what about the RAM 2500s and in my opinion, I just feel like that platform is really not that competitive anymore.
I mean you guys know I love the engine. I think it’s a great engine, but with the second gen l5p Duramax, with again its increased power numbers, it has really left the Ram 2500 diesel Commons engine on a little bit of an island. The 2024 Ram 2500 puts out 370 horsepower as well as 850 lb feet of torque, with that rather subpar six-speed transmission. So when the competition like this truck right here is putting out 100 more horsepower as well as well over 100 more pound feet of torque, it starts to make that platform. Just look a little outdated, I mean you can get an F250 with the high output power stroke and that’s going to put out 350 more pound feet of torque than that cumin, which is a lot more power.
I can hear you guys screaming at me already. So two things: yes, cumin does have a high output engine, but you can only get it in the 3500 platform which to me is just ridiculous um. Secondly, yes, the cumin may have an argument in terms of strength, reli ab, ility and Longevity, but I mean the 67 Power. Stroke is a very good engine. It’S been around for a number of years and has proven itself to be a very, very capable longlasting, reliable engine and this engine right here.
The l5p, like I have mentioned many times in this article, I think, is a very, very Stout engine. So it’s not like you’re going to get an unreliable engine if you don’t buy a cumin. All I’m saying is that Ram may need to shake some things up in the years to come here to remain as competitive as they once were. So those are the updates for the second gen l5p 2024 Duramax. Let me know what you think.
Would you guys plan on buying something like this? Does it Intrigue you always interested to hear what you guys have to say? As always, if you like, the article, don’t forget to leave that thumbs up and hopefully the weather gets better. We’Ll have some cool stuff planned in the future. But enough of me we’ll see in the next article.
