3.0 D-max reviews?

[6DoF]

looking at a 2021 Tahoe for the wife that would replace her 07 WK and my 08 GMC 2500. 1 less car around to deal with, a much nice ride, and i'll have the 55 soon (hopefully) for truck bed stuff. but we have ample trailers too.

thoughts on the new mini I6 diesel?

[6DoF]

the whole oil-pump belt thing doesn't really scare me much in the grand scheme of things. that's the only down side i've seen.

other than there being ZERO aftermarket for them yet cuz EPA ... fawk the man ...

[xj_man_646]

Other than typical modern diesel concerns and the belt driven oil pump I think they're pretty solid. A friend's dad in SE MI leased one of the trucks and loves it so far. Unconventional to most diesels it has an air to water intercooler so that adds a bit of complexity to the charge cooling system.

[6DoF]

i'm excited to try one tonight. the wife really liked the diesel JLUR over the 3.6 JLU we drove on Saturday. i also made her drive a 2021 manual window, manual trans 2dr and it was really good, she actually liked it. enough that i don't think she could convince herself that the $61k JLUR was worth anywhere near that much more than the $29 JL.

[Cobound]

:lol: I'm so glad my wife likes her 2 door JK Sahara :D

[6DoF]

so the 3.0 was nice, but defiantly not "peppy". 100% would buy a Banks derringer for it.

last night we basically decided to not decide now. we are pushing off any purchase cuz it doesn't really matter. if we really wanted to we could both get new trucks, or combine the WK and GMC into one, or simply keep going how we are. to help the just wait decision, she drove my truck to work at the hospital today to park it in the city and see how it goes. last night it was all good, but half way to work the power steering started whining and by the time she got to the tight ally and parking lot there was no power steering. "sorry babe, happy anniversary"

[6DoF]

found a buddy who gave me a GM discount code!! ordering a 2021 Tahoe with the 3.0L D-Max this week. i guess it's like a 12wk lead time.

[nblehm]

Didnt even know you could get a tahoe with a diesel.

[xj_man_646]

Yep you can get the Tahoe and Suburban with the baby Duramax now.

[nblehm]

I dont get why people want the diesels with all the emissions junk on them but cool they come in more than 3/4 - 1 ton trucks

[6DoF]

I dont get why people want the diesels with all the emissions junk on them but cool they come in more than 3/4 - 1 ton trucks

i obviously agree to a point, that's why i'm building with an old mechanical pre-BS cummins. however at this point they've been messing with the systems long enough they at least aren't new.

for me it's cost vs engine on this. trading my 2500 GMC and the WK in on this Tahoe. the 55 will eventually be my heavy hauler, but i need this to still be able to tow the YJ in the enclosed. of the 3 engine choices, the 3.0, 5.3 and 6.2, i'd rather have the 6.2. however it's only available on the highest package and costs like $10k more. between the 5.3 and the 3.0, the torque of the 3.0 is a no brainer. 383lb-ft @ 4100 vs 460lb-ft @ 1500. plus i've seen magazine reviewers getting upwards of 27mpg highway with it, and Banks should release some their magic box for it this year.

[xj_man_646]

Yeah, the technology isn't new, but it is basically as unreliable as its ever been as far as nuisance faults. I agree with Nate. 2007 will be the latest light duty diesel I ever own. Hope it works out for you.

The one thing I found odd about the 3.0 is that it uses an air to water charge air cooling system, so there is a bit more complexity to this system even over your typical diesel engine. Not that those systems are new either, just found it interesting.

[xj_man_646]

Looks like I already said that. Oops. :lol:

[6DoF]

i'm actually going to be using a water-air on the 55 as it gets built up. i like the tech and am not worried about it. hell, it's used in a ton of boosted gas engines factory as well.

[xj_man_646]

Yep that is true. It was a bit of a surprise (to me) that they went this route on the 3.0. My thought was always that the air to water charge cooling is really only advantageous when you can't get the airflow you need over a large air to air cooler, like you typically find in the cooling stack of a full size truck.

[6DoF]

Yep that is true. It was a bit of a surprise (to me) that they went this route on the 3.0. My thought was always that the air to water charge cooling is really only advantageous when you can't get the airflow you need over a large air to air cooler, like you typically find in the cooling stack of a full size truck.

air to air is just a cheaper, and probably more robust, set up. water to air can be more efficient in a smaller package, and gives you more options for routing and placement. plus the ability to run an ice tank in racing applications.

so i've been doing more reading on it recently, make sure it's what i want. short of some currently unknown manufacturing defect that kills stuff, the engineering seams really solid. they really didn't seam to skimp on this thing. some magazine reviews saw like 27mpg, and one even achieved 40mph in a hyper-mileage challenge. the torque "curve" isn't really a curve at all, it's basically ecu limited. it supposedly holds 460lb-ft from 1500-3000rpm, with still 95% of that from 1250. a good tuner should be able to unlock some major goodness!

[xj_man_646]

The world of diesel engine tuning is constantly evolving and more and more are getting out of it all together as far as I know. EZ Lynk was just hit this week for their deletes. I wouldn't be surprised if its limited to emissions friendly tunes in the 100HP-ish gain realm. Still decent, but they can't really go hog wild anymore as far as I know.

[Cobound]

So, about that '21 Tahoe :dunno:

Anyway, my JT has the 3.0 Diesel and I love it. Power, albeit a bit of a delay at takeoff, torque...the Banks Pedal Monster helps the pedal feel for sure...I have the Deringer as well but never installed it. Heard it's potentially troublesome when towing...and I do a fair bit of that w/ a SXS and now my enclosed trailer. It legit pounds DEF when towing, good lord!

Still running stock gears (3.73) on 37s and it's got snort - could probably go to 4.56 or 4.88 for a bit more pull, but not really worth it at this time.

I've had it to the mountains a few times, and while it gets solid fuel mileage, it could be a bit better. Friends with bigger meats get better, but I'm guessing that's all in drive style...so I'll take the 17-20 that it varies and live w/ it. I mean, it's a brick, right :lol:

Towed the SXS to Moab last year and got about 13 avg...going speeds above 70 so I could slow it down bit and improve, but fukall. Going to be super curious to see how it tows this year, with an enclosed trailer loaded w/ a SXS and some camping gear.

Lord knows I'm not an engineer - but you guys have any more feedback on these engines now that they've been out for a bit?

This is the beast I'll be towing -

https://scontent.ffcm1-1.fna.fbcdn.net/v/t39.30808-6/316538291_10100362518393890_7543747021501714077_n. jpg?stp=cp6_dst-jpg&_nc_cat=110&ccb=1-7&_nc_sid=0debeb&_nc_ohc=geLB05bnC2UAX_5ceNp&_nc_ht=scontent.ffcm1-1.fna&oh=00_AfBIzRd0sdG6BpFYdy3mJiFPdDt9ET2kyz7VAqKG6vrx DA&oe=63D8D605

[xj_man_646]

I have heard surprisingly little about the latest generation of EcoDiesel. I think the shift to low-pressure EGR (taking an EGR sample post-DPF where there is much less soot) was a wise choice for that engine. The previous generation had loads of issues that I think could be resolved with that move.

I worked on an under-boost diagnostic for the previous generation and learned at that time that low compression right from the factory was something they were plagued with, to the point where the boost response from a stock vehicle with low compression looked like an engine with normal compression and a 4mm hole in a boost hose.

For the trouble we dealt with, I did always enjoy the way the EcoDiesel drove, especially when paired with that 8 speed ZF.

I think I've heard rumblings of CP4 injection pump failures hitting the EcoDiesel now, but that is more of a global problem with all applications running the CP4, not isolated to FCA.

[Cobound]

Oh, I’m good.

[bbaCJ8]

Oh, I’m good.

My advice: regear that fukker ASAP. The low end torque of that diesel is a great crutch, but it's still a crutch. Same with the 8spd. Both are super capable and super forgiving. I'm sure it's perfectly competent at everything now but I'd bet the cost of a gear install that the first time you drive it after the swap you'll be saying "Jesus Christ why didn't I do this 2 years ago?!?!"

For an EcoDiesel I'd go 4.56 all day. That's what we put in pretty much all the 37" tire rigs we build, including my wife's 3.6. It's completely fine around town just like they are even with stock gears, but it shifts entirely too much for my liking on the highway. Often it'll just grab 7th and hold it, big hills it'll drop to 6th. Granted it's a high revving V6 powered cinder block going down the road on 37" tires but still, I'd like it to be better at holding real overdrive.

[Cobound]

Good advice, buddy just tossed in 4.56 in his, no feedback on his yet.

It'd probably be a better long term wear and tear as well.

I'll have to look into it...just passed 34k on it, drivetrain and extended warranty are 150k.

Thanks!

[6DoF]

we never got the order placed for the Tahoe ... was 6-8wks while shopping, 8-12wks when we tried to place the order, and 12-16wks a month later after allocations still hadn't allowed our order to be entered. canceled.

thank god too, i'm super glad i never bought into new diesels. if i had, when i came to my senses, i would have dumped it while the prices were crazy high. still great engines for those who need it, but the EPA BS doesn't makes it worth it for me over gas. that was their plan after all. while shopping, the diesel Jeeps were by far the best to drive, same with the 1500 chevy's. they also have the most potential to be way better. i'd just have to have some way to fully tune/delete the truck though.

since then i keep hearing more bad stuff about the Eco and ppl dropping their vehicles. isn't Jeep dropping it from some lines now? only stuff i've heard on the mini d-max was that these 1500 trucks are getting CRAZY mpg, even while towing.

we ended up buying a 2018 Hemi Limited WK2 for less than half the price of the 'hoe. faster, louder, fits in the wife's city parking better, just as comfy. however, we fawking hate it. endless sting of nuisance issues/quirks, and zero character. even with the 2" lift, E-rated bigger ATs, and a Stainless Works cat-back. it sounds amazing, looks pretty decent, but still rides super vague. maybe we are just jaded by the 'vette and TJ.

for a new truck, i'd get a 2500 RAM tradesman Reg Cab long bed, cheaper with no chrome. biggest gears possible, LSD, upgraded tunes, trailering bits, and send it. 6.4 standard, the reg cab is big enough that with the seat all the way back i can't get full pedal travel, and by far the best value function vs cost.

on the other hand though, the best actual truck might be a 2500 tradesman power wagon with a few creature comforts added. then throw a blower on it. all the 2500 goodness, power wagon goodness, and enough HP to make it faster than a TRX ... while being cheaper than a TRX. win/win/win/win

[Cobound]

Ah, damn...have a buddy w/ the same Grand and NOTHING but issues...they finally ditched it. Bummer you had that same deal.

While I love the JT and the diesel, if I could justify a big rig I'd be all over a Ram Prospector or the like...but I already have a hard enough time fitting into the city w/ my JT, and don't need a large vehicle for anything except an occasional long trip towing the enclosed, which I just got...so I'm "making due." Spending that coin on other items, like the cabin and such. Gotta sell one of the SXS to get a pontoon now - FWP :lol:

You guys and your reg cab long bed stuff - I could never...and that is why they have options :rock:

I wondered why I never heard about the 'Hoe...now I know!

[xj_man_646]

Yep, EcoDiesel is going away after 2023. Not sure how long the mini-max will last.

[6DoF]

as the EV BS starts to die down, i feel like the small diesel will make a comeback. that's why they still launched the mini-max.

biodiesel is easier to make with higher yield than ethanol. better MPG, etc.

[xj_man_646]

The problem is that it is such a pain in the a$$ to bring to market, that it is almost not worth it in a lot of cases. I'll be curious to see how the mini-max sales do in the long-ish term; the diesel Cruze was killed off in 5 short model years.

Large displacement NA V8s are returning to the truck segment because diesel is so costly in ownership.

Hyundai and Mazda were both slated to bring small diesel SUVs to the :us: but the effort to certify meant they eventually killed them off shortly after I left Bosch.

I do not have high hopes (long term) for diesel in the light duty segment.

[6DoF]

The problem is that it is such a pain in the a$$ to bring to market, that it is almost not worth it in a lot of cases. I'll be curious to see how the mini-max sales do in the long-ish term; the diesel Cruze was killed off in 5 short model years.

Large displacement NA V8s are returning to the truck segment because diesel is so costly in ownership.

Hyundai and Mazda were both slated to bring small diesel SUVs to the :us: but the effort to certify meant they eventually killed them off shortly after I left Bosch.

I do not have high hopes (long term) for diesel in the light duty segment.

under the current mafia.gov direction, agreed, they have no chance. i feel like they'll be re-evaluated when it becomes politically convenient.

[6DoF]

EV is probably easier to road trip than a propane/CNG rig though ...

but WMO makes a great local fuel subsidy ;)

[xj_man_646]

under the current mafia.gov direction, agreed, they have no chance. i feel like they'll be re-evaluated when it becomes politically convenient.

Its not even the .gov that is the issue, it's largely driven by CARB since certifying for two markets in the same country doesn't make sense. What will happen when the CARB market is no longer allowed to buy new ICE-powered vehicles, but the rest of the states are? No idea...my guess is we will default to the EPA regulations, which are pretty similar to CARB, CARB just goes a bit above and beyond.

EPA is more involved with the enforcement of those doing the dirty deletes.

[xj_man_646]

but WMO makes a great local fuel subsidy ;)

Don't do that with a new diesel unless you want to destroy your aftertreatment system (and probably fuel system) and not have it covered under warranty :lol:

[6DoF]

Don't do that with a new diesel unless you want to destroy your aftertreatment system (and probably fuel system) and not have it covered under warranty :lol:

a buddy who works at Cummins as an applications engineer said the only difference between their full emissions highway engine ... and the military "run anything you can pour in the tank" is the after treatment. i guess you can delete new stuff and still run oil.

[xj_man_646]

Yeah military stuff is a whole new animal. They don't get any of the glorious air cleaning aftertreatment that we do. I wasn't sure if they need a different fuel system or not...surprising that they don't.

[6DoF]

i don't know, under those pressures i can't imagine the slight viscosity change making that much difference. keep the fuel filter in good shape n go. but hydraulic fluid and oil that's been continuously pumped thru a filter is probably cleaner than what comes out of a station pump really.

but the after treatment junk can just piss off

[xj_man_646]

The .gov mainly uses jet fuel and diesel. I know for sure today isn't like the old multifuel days where you truly could run on almost any petroleum product. Who knows, doesn't matter...the current military stuff won't be available to the public for a long time, if ever :lol:.