The Best Inline-Six Cylinder Engines Of 2020


The 3 Best Inline-Six Cylinder Engines For Cars - 2020 Model Year
Why I6 Engines Are Better Than V6 -
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Inline-six cylinders are making a comeback. Now that smaller turbocharged engines offer better power and better fuel economy, smooth I6 engines are making their way back into engine bays. The three best for 2020, according to Ward's Auto, in the 3.0L I6 in the BMW M340i (B58), the 3.0L I6 in the Mercedes GLE450 (M256), and the 3.0L I6 in the GMC Sierra 1500 (Duramax 3.0L).
Each of these engines are quite different, even though they're all the same displacement. The BMW is purely gasoline, the Mercedes is an electric-gasoline hybrid, and the GMC is a diesel. There's a wide variety of innovative technology used, like twin-scroll turbochargers, variable intake manifolds, variable geometry turbochargers, 48V hybrid systems, infinitely variable valve lift, and incredibly high fuel injection pressures. Check out the video to learn all about 2020's best I6 engines!
*Related Videos - KEEP LEARNING!*
How Inline-Six Cylinders Work -
Why Inline-6s Are Coming Back -
Twin-Scroll Turbochargers -
Variable Geometry Turbochargers -
Electric Superchargers -
Air-to-Water Intercoolers -
How BMW Valvetronic Works -
Why Diesels Make More Torque -
Variable Intake Manifolds -
Torque vs Horsepower -
Toyota Supra Engine -
Ward's Auto 10 Best 2020:
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  • Court
    Court2 dager siden

    So the my question is, is the high pressure injection good/reliable, or an expensive disaster waiting to happen?

  • Nik Gnashers
    Nik Gnashers4 dager siden

    BMW's B58 is the best current ICE imo.

  • Mic Cruz
    Mic Cruz8 dager siden

    I have to disagree on the drag race analogy. If you only had one gear it would be correct. The transmissions would be the difference. Diesel would shift sooner, thus keeping it in the optimum power band.

  • Plate Productions
    Plate Productions9 dager siden

    I like how mercedes made their engine feel more like a naturally aspirated engine by making it more complicated

  • François Parent
    François Parent12 dager siden

    BMW Valvetronic and VANOS work in conjunction with each other

  • Fierce man
    Fierce man20 dager siden

    It was good to learn about the differences between the inline 6 engines of each manufacturer!☺️

  • kenny master
    kenny masterMåned siden

    Globally what is the reliability of GMC's those past 10 years for exemple ?

  • JacobSmith
    JacobSmithMåned siden

    The Aussie Barra is a beast strapped with a turbo. I doubt these I6’s can compete with power

  • Tim Doan
    Tim DoanMåned siden

    All three are unreliable!

  • 60FPS
    60FPSMåned siden

    wonder if you can modify the gmc at all

  • Dillon Fortenberry
    Dillon FortenberryMåned siden

    i dont want science... i want engine noises. fast forward, disliked video.

  • Herbert von Sauerkraut unterhose
    Herbert von Sauerkraut unterhose2 måneder siden

    I stick with 4cyl diesel engines, Peugeot make the best. Registration is also cheaper.. The more additional boys put on the engine or car the higher the repair costs and downtime.. This can negate any efficiencies or cost savings from new technologies.. But, of you can afford it who cares.. Just offload the car and upgrade every few years and pass the problem on

  • Mike
    Mike2 måneder siden

    The main problem with the GM 3.0L engine is that it is attached to a GM transmission.

  • Mr. Kriss
    Mr. Kriss2 måneder siden

    Great Videos Jason ! Thanks For Sharing Your Knowledge & Research !

  • Rowdy Flyer1903
    Rowdy Flyer19032 måneder siden

    This all fine and good. You have explained all the gadgets connected to the engine to improve performance. You have also explained that come back of the six is due to the same reasons the v6 was created, in that it was a natural extension of the current manufacturing process. Do you have an a comparison or explanation of advantages of engine configurations and why?

  • jaytmtb
    jaytmtb2 måneder siden

    Love these videos, very informative even for someone who knows a bit about the subjects, thank you and keep up the great work :-)

  • Nelson Swanberg
    Nelson Swanberg2 måneder siden

    I hope GM is not making their own diesel. More rpm usually means more hose power.

  • Rob Rosenblatt
    Rob Rosenblatt2 måneder siden

    ...if someone set out to create a product that would be unexpectedly expensive , keep a variety of auxiliary businesses taking tons of the owners money ( like gas, spark plugs, air filters, muffler, transmission, gasket, fuel filters, waters pumps etc ), pollute the environment, and need to be totally replaced after a short period of time...they would have invented the internal combustion takes a real genius, like this fellow, to understand and educate us common people the likes of all these cars...but after listening to his knowledgeable lectures, there comes only one conclusion...after looking at the wires, pistons, flames and dirty oil whether the best 3 or the worst three....the days of the ICE machine are coming to and end real soon...

  • Cody
    Cody2 måneder siden

    I own a BMW I6 N57 Diesel engine and this thing is smooth as butter. 90k miles on it. Knock on wood, not one repair..

  • ultra2050
    ultra20502 måneder siden

    You missed the main advantage of the electric motor on the mercedes engine. It is beltless.

  • Allen Loser
    Allen Loser3 måneder siden

    Who drag races in a diesel pickup truck? The torque of the diesel engine means the pickup can haul a heavier load from a stop to the legal speed limit.

  • Neil Macleod
    Neil Macleod3 måneder siden

    Electric motor helps speed up take off, then drags the engine while it recharges the battery . Mmm think I'll keep my cummings

  • Neil Macleod
    Neil Macleod3 måneder siden

    Again an interesting video ruined by far to many ads .

  • Pedro Areias
    Pedro Areias3 måneder siden

    No, power is not "what matters". In the early nineties, we had in Europe NA gasoline cars with low capacity and high rev ceiling and then direct injection Diesel engines came in the late nineties with lower power and much higher torque. Everyone swapped. Why? They are much faster in the real world, don't require high revs and due in part to the torque, consume a lot less. Even with turbocharged gasoline/diesel, a 150 hp Diesel tends to be much faster in the real world than a 180 hp gasoline engine. Of course that's because few people go above 4000 rpm in the real world.

  • Steven Carter
    Steven Carter3 måneder siden

    You left out the best inline six of all...the Aussie ford Barra...we boost them up to 1400 hp no problem

  • Nor Dic

    Nor Dic

    Måned siden

    Yup, the Barra is the king of the hill for i6 engines. A factory cast block and head barra can make >2500hp.

  • Jayson Bourne
    Jayson Bourne3 måneder siden

    This man looks young and old at the same time

  • Achilles HELLAS
    Achilles HELLAS3 måneder siden

    I want an inline 12 cylinder engine

  • Ruzbihan
    Ruzbihan3 måneder siden

    so more torque the better to use the turbo charger than supercharger..

  • N. Elliott
    N. Elliott3 måneder siden

    Timing system on rear of engine.. Do I need to say that again?

  • alex luke
    alex luke3 måneder siden

    Hmm one diesel and two petrols...why not comparing apples to apples...let's say GMC diesel vs BMW 540d vs E400d diesels And the instead od GMC diesel it could fit a gasoline version here.

  • alex luke
    alex luke3 måneder siden

    Why not using the AMG 53 engine instead of 450

  • Jonathan Garzon
    Jonathan Garzon3 måneder siden

    That's sad. Gmc- which is all garbage post 2000 Bmw and mercedes- which make great machines with terrible electronic self destruct systems. Basically buy inline 6 pre 1987 From anyone if if you want something that lasts more than 100k

    LUNITIC WILL3 måneder siden

    "For 2020" sad Ford 4.9l noises

  • said hossain
    said hossain3 måneder siden

    best engine layout. Most balanced. In v must be at least a v8.

  • Anthony Gillesse
    Anthony Gillesse3 måneder siden

    That B58 must be a great engine! Their putting them in the Lexus now. You go BMW

  • Speed Master
    Speed Master3 måneder siden

    Another IL6 n52b25 is soo smooth and reliable. Linear power delivery

  • Scott Gardner
    Scott Gardner3 måneder siden

    I bet that Mercedes engine is pretty awesome while its new. All kinds of throttle response I bet.

  • Hdhd Dhdb
    Hdhd Dhdb4 måneder siden

    .... الدكتؤر

  • Hdhd Dhdb
    Hdhd Dhdb4 måneder siden

    دهؤن نايم

  • Hdhd Dhdb
    Hdhd Dhdb4 måneder siden

    علبة بنادؤل

  • Jesper Danielsson
    Jesper Danielsson4 måneder siden

    Why dont they use higher pressure on gasoline engine?

  • veleriphon
    veleriphon4 måneder siden

    No mention of Barra. BMW and Mercedes repair costs outweigh their inclusion. Then again, 3.0l list.

  • Gene Capeder
    Gene Capeder4 måneder siden

    Well done Jason - clear, concise and valuable.

  • Eric B.
    Eric B.4 måneder siden

    MAZDA's 2.5 l. turbo also has a way to keep the air flow fast at low RPMs.

  • Kevin Tullock
    Kevin Tullock4 måneder siden


  • Bernie K
    Bernie K4 måneder siden

    Australian Ford turbo barra motor will eat these for breakfast and not even burp. 1000 bhp on factory stock motor is possible and Street able.

  • Lupe Voeo
    Lupe Voeo4 måneder siden


  • Conrad Sealy
    Conrad Sealy4 måneder siden

    RBX28DETT. From 2005. 178hp/liter in the R34 Nismo GTR Z-tune.😉

  • CrazyBubaCZE
    CrazyBubaCZE4 måneder siden

    Interesting video, but as European I must ask, why don't comparing 3 diesel 3l in-line 6, BMW and M-B build them too

  • Tony Kwok
    Tony Kwok4 måneder siden

    Mercedes will be the most expensive to fix!

  • G
    G4 måneder siden

    Inline 6's are just cool. The sound can be amazing. BMW K1600...

  • Nick Salter
    Nick Salter4 måneder siden

    A best straight 6 engine video without mentioning bmw would be sacrilege

  • Justin Stephenson
    Justin Stephenson4 måneder siden

    Jeep's inline 6 4.0l

  • Faceless Assassin
    Faceless Assassin4 måneder siden

    Buddy, only Americans needs super high HP. And other people love offroading more than top speeds. If you say torque doesn't matter.

  • NU MOO
    NU MOO4 måneder siden

    All I wanted to know is who gets to the 1/4 mile flag first🤔....well?

  • You know Shum
    You know Shum4 måneder siden

    Would you be able to make a short video about the low pressure turbo on the 2016 Volvo t5 ?

  • Jay Charland
    Jay Charland5 måneder siden

    Your wrong on power.vs torque Power burns the tires off. torque moves heavy loads. A pickup needs torque not horse power . look at the 5.9 Cummins 12 v 170 horse power but can pull any thing you want. Gas motors suck gas and have little torque a 454 with 450 horse power only has 450 foot pounds of torque and. Can not pull heavy loads well a 5.9 Cummins with 170 horse power and 470 foot ponds will out pull it ever day of the week and use half the fuel. You need to learn about diesel engines son. If you have 6 I a line your good to tow 606 MERC. 5.9 Cummins Dt 466 IH 3306 CAT 3406 CAT EVER THING ELSE OUT THERE IS JUNK.

  • RJM
    RJM5 måneder siden

    Power only matters in a race. If you mostly use your truck off road at low rpm then high torque at low rpm is king.

  • RJM
    RJM5 måneder siden

    When did people start saying lb-ft instead of ft-lb and why?

  • Ken Smith
    Ken Smith5 måneder siden

    Has anyone done the math to find how much CFM is lost in all the intake tubing and bends?

  • Juan Pablo Zawadzki
    Juan Pablo Zawadzki5 måneder siden

    Good video - even though seems you're talking with a potato inside the mouth

  • Itr 1244
    Itr 12445 måneder siden

    barra, 2jz, bmw's I6

  • Indrid Cold
    Indrid Cold5 måneder siden

    It is unlikely any of these inline six engines will last as long as the AMC 242ci I6 I have in my aging TJ. As of a few days ago, there is 411,500 miles on the odometer and climbing. The engine has not been rebuilt and has not had any gaskets replaced. I did tighten all joining surfaces two years ago to make the gaskets work better, but all is original, including the water pump and the infamous 0331cylinder head for the 2000 and 2001 years. I even overheated twice when I hit a bird and it ruptured the radiator. Compression is still good. The nearly legendary AMC valve rattle when the engine is cold has been with the engine since just over 200,000 miles. But once it gets to normal operating temperatures, the AMC rattle is goes away.

  • Jins John
    Jins John5 måneder siden

    What about nissan vtc 4800 in patrol y61. That is one of the best inline 6 engine

  • Darrell Ferguson
    Darrell Ferguson5 måneder siden

    Cummins 6.7 liter Diesel is the best in-line 6!

  • TO-3 2N3055
    TO-3 2N30555 måneder siden

    How does a twin squirrel.....

  • niceguy100000
    niceguy1000005 måneder siden

    By far the best inline 6 engine available* in 2020 is the Toyota 1HZ. Fun fact: it has no check engine light so it can't fail :-). (*in some countries)

  • Tu Chenz
    Tu Chenz5 måneder siden

    om606 every time

  • Hakan Chunton
    Hakan Chunton6 måneder siden

    Why no cummins

  • Charlie


    5 måneder siden

    Because he's talking about gas engines.

  • Bob Pegram
    Bob Pegram6 måneder siden

    The Diesel also runs without a throttle butterfly valve. Like the BMW gas engine. Fuel to air ratio is what controls power output in them and is also what makes emissions control difficult with them, as I understand it. Does BMW use the same valve opening technique on their Diesel sixes? Who makes the GM Diesel, GM itself? Are all three engines roughly 3 liters displacement? Yeah, I'll go look at the Wards article.

  • Andrew
    Andrew6 måneder siden

    You made this in January. What if someone came out with a better engine in February, March, April, May, June, July, August, September, October, November or December? People are jumping the gun to get a video out and get views.

  • Charlie


    5 måneder siden

    Have you been to 2020? It's July and so far all that's happened is half of Australia burned down, the Arctic caught fire, a plague of locust destroyed Africa twice, the police started teargassing housewives, and hundreds of thousands of people have died from the plague. Nobody is making a better I6 this year.

  • Issam Ghosh
    Issam Ghosh6 måneder siden


  • Stan Dup
    Stan Dup6 måneder siden

    You need to look at Australia's I6 engines. Ford had the SOHC 4.0 I6 and later a DOHC 24v 4.0 I6 (Barra) and came from factory with a turbo. Both are torque monsters

  • iZajRes GS
    iZajRes GS6 måneder siden

    I love what you said about torque. That's what I never understood after all those years.

  • Edysin Simon
    Edysin Simon6 måneder siden

    Not even halfway thru 2020 and yet we have the winner? TBH....I'd vote for the diesel motor simply because it's a diesel with better fuel milage. The durability issue is also to be determined at a later date.

  • Drupthop
    Drupthop6 måneder siden

    Hey Jason, I would like to see a comparison between equal displacement inline I6 and a VR6, I want to be convinced that a VR6 package or VR8 package isn't the better configuration for Longitudinal motor placement in an engine bay, if the VR design has similar torque/power? Thanks

  • Jack PRick
    Jack PRick6 måneder siden

    Really love your videos. One question: which engine is the easiest and cheapest to maintain? Ok those are two questions but it is why I love my cummins 5.9. I also have an e39 530 and love that engine too although more expensive and more costly to maintain than the cummins. I looked at the new GM in line 6 diesel thinking it might be easy to work on, but no, cant even see the engine with all the ancillary equipment.

  • Jamster
    Jamster6 måneder siden

    N54 still purrs

  • Kasper Hansen
    Kasper Hansen6 måneder siden

    Funny how GM has the most wins in Ward's Best, when GM isn't nearly as successful at the International Engine of the Year Awards. I think they are a little too "red, white and blue" at Ward's...

  • sergiu pavlov
    sergiu pavlov6 måneder siden

    Very well explained, thanks so much

  • joseluis arevalo
    joseluis arevalo7 måneder siden

    RB26DETT ftw

  • Shutozoku
    Shutozoku7 måneder siden

    2JZ and RB26DETT is the legend I6 engine

  • John Stewart
    John Stewart7 måneder siden

    So very interesting.

  • micky dee
    micky dee7 måneder siden

    Mercedes E53 AMG 429 hp and 384 lb-ft. Why didn't you use that engine for comparison?

  • Choo bam
    Choo bam7 måneder siden

    Until you factor in BMW’s and Mercedes reliability.

  • Dependant Director
    Dependant Director7 måneder siden

    Bmw will always be the best. The most underrated brand ever.

  • ManudB
    ManudB7 måneder siden

    Before watching this video I am gonna say that BMW makes the best I6 engines period.

  • Alamgir Adel Shah Muhammad
    Alamgir Adel Shah Muhammad8 måneder siden

    GLS 450 4 matic 2020 Inline 6-Cylinder Spark-Ignition Engine, M256 is hybrid ?

  • Lash LaRue
    Lash LaRue8 måneder siden

    I like German engineering, but I have a problem with the German marketing departments. I don't want to sacrifice all of my Man Cards on some limp-wristed fruit car driven by neurotic foppish dandies with more money than know-how. I'd like my girlfriend to be more high-maintenance than my vehicle, thanks.

  • Pavlos Saridis
    Pavlos Saridis8 måneder siden

    The 6 cylinder bmw diesel engine is amazing as well

  • playasurf1000
    playasurf10008 måneder siden

    the Aussie built barra 4 litre puts those engines you got up there to shame

  • Hyerin Jun
    Hyerin Jun8 måneder siden

    no inline 6 can beat toyota jz engine

  • Chrispewkreme
    Chrispewkreme8 måneder siden

    B58 S55 N55

  • Inderan Naidoo
    Inderan Naidoo8 måneder siden

    Hi Jason, Which inline 6-cyclinder engine would you personally rate as the all-round best?

  • Swamp Robin
    Swamp Robin8 måneder siden

    “Once we get this in to its higher RPM region, it’s done. It’s going to stay ahead for the rest of the race forever, because it has more power, and power again is what matters” Unless the race is over. Consider 0-60 drag races between F-150s with 3.5 EcoBoost (375 peak hp) and 5.0 Coyote V8s (395 peak hp). The power of the V8 doesn't exceed the turbo 6 until nearly 5000 rpm, by then the race is over. The V8 would probably win a 0-100, but that's not legal in the US. Separately, it would be great to see a video explaining why an F-350 dually with a 475hp diesel is rated to tow so much more than the same truck with a 430hp gas engine.

  • david njoroge
    david njoroge8 måneder siden

    Jason if power mater's more than torque?why are hybrids the in thing in hyper cars, electronic motors have instant torque,and torque is the reason all trucks run diesel engines,

  • GrotrianSeiler
    GrotrianSeiler8 måneder siden

    God Jason, your videos are so interesting to watch. Very well done. Super clear.

  • Tomasz Kudłacz
    Tomasz Kudłacz8 måneder siden

    Jason + 2 feet breaker bar = 2 jason-feet of torque

  • richiesworld1
    richiesworld18 måneder siden

    RIP The mighty Barra!

  • Eric Bauer
    Eric Bauer8 måneder siden

    For me, I'll take an electric motor.