2.8L Duramax with a tune

thetruck454 · March 27, 2014

Up front I will say this is all subject to change when the diesel comes out. I'm going with the diesel over the v6 for power, the efficiency gain will just be a bonus. Stock I have no doubt the v6 will be much quicker, but with a good efilive/hptuner tune I bet the diesel could hold its own. Even if the diesel isn't quicker after the tune, I bet it will feel quicker because of the low end tq vs the high reving v6.

bboyce536 · March 29, 2014

Comparing the ram v6 to the v6 in the Colorado is moot. The v6 is the base emgine in the ram whereas the 3.6 will be the premier gas engine in the Colorado. My guess is the diesel will cost about 2k more then the v6. Only thing I can think of holding the diesel back till 2016 is maybe it's getting the new 9 or 10 speed to absolutely blow mpg and power out of the water. Even if that is the case, the diesel will be worth it for those who need the power for hauling and also need efficiency.

Put a load on thr v6 and you will be lucky to see 20mpg but put a load on the diesel and you won't even notice it. That's my biggest gripe with gas engines...I regularly haul bikes and small loads in the bed of my truck and can't believe how bad my mpg drops on trips.

Really hope gm delivers with this truck!

GPGuy · April 2, 2014

Very interested in seeing what the numbers are in this engine...would definitely have to do some number crunching to see if the extra cost initially and on things like oil changes will be worth the mpg advantage.

thetruck454 · April 4, 2014

I highly doubt the diesel will make much financial sense over the v6 until well past 100k miles. I'm interested in it because its the only option for torque since they decided to put a car v6 instead of the 4.3.

amxguy1970 · April 7, 2014

I highly doubt the diesel will make much financial sense over the v6 until well past 100k miles. I'm interested in it because its the only option for torque since they decided to put a car v6 instead of the 4.3.

Only option for torque? Car engine? Misinformed are we? I guess you are comparing the 4.3 to the 3.6? Last I saw these engines were hauling around a 5k lb CUV with a torque curve that starts lower than the 4.3 and peaks lower. Yeah, some car engine.

Hey, sounds good on the the diesel though, you do know you will have to replace the timing belt on that thing around 100k miles right? The V6 uses a chain...

Tyler

thetruck454 · April 7, 2014

Only option for torque? Car engine? Misinformed are we? I guess you are comparing the 4.3 to the 3.6? Last I saw these engines were hauling around a 5k lb CUV with a torque curve that starts lower than the 4.3 and peaks lower. Yeah, some car engine.

Hey, sounds good on the the diesel though, you do know you will have to replace the timing belt on that thing around 100k miles right? The V6 uses a chain...

Tyler

I didn't mean to sound like I had an attitude, but I sure got a response from you. I don't usually get involved with internet arguements, but I can't leave this one alone.

Below is the gm supplied dyno of the LFX 3.6 that the colorado/canyon will be getting. This comes from the terrain which has matches the proposed hp/torque of the colorado/canyon To achieve say 250 lb ft of torque the engine has to rev to about 3250-3500 rpm with a peak of 270 lb ft at 4800 rpm

Now this is the dyno of the LV3 4.3 liter from the silverado/sierra. To make that same 250 lb ft this motor is only spinning at about 1750 rpms. This engine then peaks at 305 lb ft at 3900 rpms. It doesn't even come down to the 3.6's peak of 270 lb ft until about 5250 rpms which at that point the 3.6 is starting to decline. Even after that point the 4.3 sill makes more torque than the 3.6 for the rest of its limited rev range. So from approximately 1750-5600 rpms the 4.3 has the 3.6 covered, in some areas by what looks like 40+ lb ft.

I'll show another dyno of the LFX from a srx that appears to be tuned for more low end. It appears to match very closely with the 4.3, until its peak of 265 lb ft at 2400, but then as it slowly tapers off the 4.3 keeps climbing to 305 lb ft and maintain a torque lead by as much as 40 lb ft until it signs off at 5600 rpms.

To be fair to you since you did mention the 5000lb+ suvs below is the dyno from the LLT version of the 3.6.that the Lambda chassis crossovers you speak of (traverse, enclave, acadia) use. If you were an "informed" person you would know that this is not the engine the colorado/canyon will use, but I'll include it none the less. To use the same 250 lb ft of torque it appears to make it around 2250-2500 rpms. This is not far off from the LV3 4.3, however the 4.3 keeps on climbing and stays above the LLT. The story is the same for this version of the 3.6, the 4.3 has it covered until it checks out at 5600rpms.

In all cases the LV3 4.3 maintains a serious torque advantage over the versions of the 3.6 until it signs off, hense my car motor comment. Next time you call someone out for misinformation, please make sure you yourself are actually informed.

On a side note your comment about the 2.8 duramax using a timing belt appears to be correct based on a quick google search. That strikes me as odd, learn something new every day I guess

Edited April 7, 2014 by thetruck454

amxguy1970 · May 16, 2014

I didn't mean to sound like I had an attitude, but I sure got a response from you. I don't usually get involved with internet arguements, but I can't leave this one alone.

Below is the gm supplied dyno of the LFX 3.6 that the colorado/canyon will be getting. This comes from the terrain which has matches the proposed hp/torque of the colorado/canyon To achieve say 250 lb ft of torque the engine has to rev to about 3250-3500 rpm with a peak of 270 lb ft at 4800 rpm

Now this is the dyno of the LV3 4.3 liter from the silverado/sierra. To make that same 250 lb ft this motor is only spinning at about 1750 rpms. This engine then peaks at 305 lb ft at 3900 rpms. It doesn't even come down to the 3.6's peak of 270 lb ft until about 5250 rpms which at that point the 3.6 is starting to decline. Even after that point the 4.3 sill makes more torque than the 3.6 for the rest of its limited rev range. So from approximately 1750-5600 rpms the 4.3 has the 3.6 covered, in some areas by what looks like 40+ lb ft.

I'll show another dyno of the LFX from a srx that appears to be tuned for more low end. It appears to match very closely with the 4.3, until its peak of 265 lb ft at 2400, but then as it slowly tapers off the 4.3 keeps climbing to 305 lb ft and maintain a torque lead by as much as 40 lb ft until it signs off at 5600 rpms.

To be fair to you since you did mention the 5000lb+ suvs below is the dyno from the LLT version of the 3.6.that the Lambda chassis crossovers you speak of (traverse, enclave, acadia) use. If you were an "informed" person you would know that this is not the engine the colorado/canyon will use, but I'll include it none the less. To use the same 250 lb ft of torque it appears to make it around 2250-2500 rpms. This is not far off from the LV3 4.3, however the 4.3 keeps on climbing and stays above the LLT. The story is the same for this version of the 3.6, the 4.3 has it covered until it checks out at 5600rpms.

In all cases the LV3 4.3 maintains a serious torque advantage over the versions of the 3.6 until it signs off, hense my car motor comment. Next time you call someone out for misinformation, please make sure you yourself are actually informed.

On a side note your comment about the 2.8 duramax using a timing belt appears to be correct based on a quick google search. That strikes me as odd, learn something new every day I guess

Damn, doing a quick google search for graphs and I get brought to this. Misinformed, that is funny. You are making assumptions based on some graphs not even entailed to the Colorado's. Yes, I know they are using a version of the LFX "tuned for truck duty", do you know what those changes are? Revised heads, new intake manifolds and revised tuning; more than just a computer adjustment. You posted the graph of the SRX which is better at showing the truck capabilities of the engine but still not fully. You will notice where the torque peaks, well below the 4.3 where as with the 4.3 you have to rev it to get its torque. Yes the graph is fairly flat but look at how hard it is dropping at 5k with the 4.3, that is where horsepower comes in to play. You want both across the board, that should be a no brainer. You can't rely on tons of torque down low in the first half of the rev range to keep a load moving up a mountain with a gas motor. Case point that old 4.3. Tons of torque down low for moving around town, on the highway it was crap. We had three of those motors and a 4500 lb boat. A better match would have been another 50hp and a 30 reduction in torque. Ever hear the saying torque gets you there and horsepower keeps you there? Same thing applies here.

Now using that SRX graph you can see it isn't a serious advantage, the SRX stays pretty much flat once it hits its peak at 2400 rpm then stays around 255-260 until 6k rpm. The 4.3 hits about the same tq number around the same rpm but then keeps climbing until it peaks at 4k rpm. Why is it peaking so high if it is a truck motor? I thought they were supposed to peak down low? Give me a low tq peak and high rpm hp peak any day over both high, that just shows the motor needs to be revved out to get all its power.

Want another example? As much as it pains me to say it the 3.6 "car motor as you put it" from the Ram out performed the 4.3 "truck motor" towing up the Davis damn. Hmm, what does that say?

Motors aren't designed like they used to. Look at the 6.2 in the truck, that just has a intake manifold change and tune and look at the change it made to #'s and peaks. Why can't the 3.6 get the same with more drastic of a change?

Guess I will close this the same way you did. Next time you want to make false claims that are uninformed (making assumptions based on other vehicles) maybe you should wait to make those claims until you yourself are informed and it is actually released to see and test before pre-labeling it. Look at all the people who were knocking the design of the colorado before it was released based off the foreign version, now look at they are saying. Same thing here, wait until all the specs are released before making assumptions and name calling (the motor not person fyi). Just based on the above those two motors are to close to call in terms of #'s and performance. It wouldn't surprise me one bit if the lower torque peaking of the colorado combined with a 3.73 rear end makes the truck feel stronger down low than the 4.3 does in the full sizers, it can be turned and adjusted that way.

Tyler

Edited May 16, 2014 by amxguy1970

miniceptor86 · November 26, 2014

Car engine? Truck engine? When I was a kid people would be complaining that the large displacement car engines were truck engines.

There are a lot of factors many of which we non- design team members will never know that go into making decisions such as the engine choices for the Twins. Ability to meet present and future emmissions standards, fuel economy, ease or ability to modify the engine to meet present needs... I have to agree with Tyler that the 3.6 in the twins has the best of torque and horsepower and fuel economy under low load. The V6 twins only have a 3.42 rear gear available at this time but the over all reduction in first is lower than my Tacoma with a 3.73 so I think they will pull a 5k trailer just fine. Torque on the bottom and high rev'in horsepower on top, ye ha let'er rev and listen to the music!

Nargg · December 5, 2014

I believe the current 4.3L gas engine is seriously under tuned, and the current version does put out 305HP same as the 3.6L. But seriously more torque. Plus the CID, I bet it'd get much better MPG than the 3.6L does. If and when GM offers an SS version of this truck, I do wonder what engine they'll use...

Edited December 5, 2014 by Nargg

thetruck454 · December 8, 2014

I just had to update this article to show the actual GM dyno if the LFX in the Colorado. Compare it to the LV3 and you can see nowhere is the 3.6 ahead in torque until very high in the rpm band. Now that more details about the colorado are out I really think the reason gm used that was because it bolts to the same 6l50 as the 4 cylinder and it uses the same ECU. The 4.3 bolts to the 6l80 and uses the same ecu as the v8's so it would require more manufacturing differences. I bet the 3.6 met their goals and was cheaper to manufacture (not the engine itself, just vs having requiring different parts vs the 4.3. I still hold out the 4.3 would be better truck engine, but even GM said their target for this truck was crossover buyers more than truck owners so there is NVH to consider and sound etc. I am a little worried about how well that 6l50 will hold out towing almost 7000 lbs with a 4400lb truck, but I'm betting very few people will tow enough to stress it.

Chris · December 8, 2014

It was used for CAFE and cost reasons. With the new CAFE regs, every MPG matters.

Cowpie · December 22, 2014

Too bad, in all of that, you did not show the graph on the 2.8L diesel going in the Colorado. It outclasses all of that other stuff. It reaches peak torque at 2000 RPM and the peak torque is as good as most stock small block V8's. I don't have the graph for this new 2.8L, but in almost every detail, it seems to be a carbon copy of the VM 2.8L diesel in my 2006 Jeep Liberty. Only change I can find is the Garrett water cooled VG turbo will now be a Honeywell water cooled VG turbo, the Bosch Common Rail fuel system in my Jeep putting out 18,000 psi at the injectors will now be a Denso Common Rail putting out 20,000 PSI at the injectors. Other than that, virtually the same engine.

Considering the 2.8L will have peak torque at the RPM band that most folks use vehicles at, and will do it all while getting substantially better mpg than the small block V8's, it could be a killer deal for some folks. The 2.8L in my Jeep was EPA MPG rated at 27 mpg highway. it regularly busted 32 mpg highway. This one should do as well or better if driven right.

Edited December 22, 2014 by Cowpie

Cowpie · January 31, 2016

Just got a note back from Green Diesel Engineering, the folks who did a great tune job on my 2006 Jeep Liberty 2.8L VM diesel (the base engine for the 2.8L Dmax) and they just got back with me....

We have a Colorado on order, and as soon as it gets delivered we’ll get to working on it for having a product available soon. The engine in the Colorado is a very close derivative to one used in the Jeep Wrangler overseas that we’ve had experience with dating back to 2006 so it shouldn’t take long to make good progress on how it runs.

Stay tuned, we’ll start posting on our website and various forums once we’re making headway.

Regards,

Matt

GDE Calibrator

greendieselengineering.com