The Diesel Episode (S06E01)

Chris Duke tells you everything you ever wanted to know about diesel engines.

Episode Links

E3 Spark Plugs
Blackstone Laboratories
NHRDA – National Hot Rod Diesel Association
Milestone Paint & Body

Tools & Products Mentioned

Episode Notes

This is the 75th episode (S06E01). Welcome to the season 6 premiere! We have an exciting season planned for you! We have a new 3D animated intro (we’ve gone from the F-150 to a Mustang), along with other new motion graphics for the show!

In this 75th episode, Chris tells you everything you ever wanted to know about diesel engines. For the past 5 seasons we haven’t talked about them, and we’re making up for it by devoting an entire episode to them! Chris talks about how diesel engines work compared to gas engines, maintenance tips, the different types of diesel fuel that exist, and of course various aftermarket products that can improve your diesel engine’s performance.

This episode features our regular segments, Letterz and Partz.

In Letterz, Chris answers viewer mail and shows you the newest member of the Letterz set, a custom-painted Motorz/Craftsman guitar from Milestone Paint & Body! In Partz, Chris shows you some really cool ratcheting clamps from Craftsman, how to keep your garage cool during the hot summer using a Port-A-Cool Cyclone 3000, and how to keep everything tied down in the bed of your truck using AMP Research’s tie-downs.

A special thanks to Action Turbo (Santee, CA) for the turbo cut-away loaner, and to Butch Olhausen for loaning us his F-250 for filming!

As always, be sure to stick around to watch our out-takes at the very end during the credits!


This episode features an original Motorz theme song by Jeremy Pritchard.

  1. What I don’t like is the cost of filling up a diesel truck. If it was a compact truck with a diesel engine, like the Ford Ranger, the Dodge Dakota, Toyota Tacoma, or a Nissan Frontier, I would think it’d be less expensive to fill up.

  2. How to make a gasoline engine more efficient than a diesel: Step 1, buy an iron-block 426 HEMI. Step 2: Get a 13:1 compression ratio out of it. Step 3: Supercharge it. There. More torque, more power, same (if not better) MPG, and same reliability as a diesel. Old iron-block 426 HEMI’s are the bullet-proof engines of the gas world. That block will never crack, no matter what you do to it.

  3. Ready to get my diesel truck back…needed new injectors. Any who watch a video about diesel engines!…

  4. I love diesels, but the new quiet and stinkless diesels get lousy mileage, unreliable, and expensive to maintain. You are better off with a gasser. Ultra low sulfur diesel has less energy than pre 2007 diesel plus usually costs 70 cents more per gallon.

  5. Why no discussion about emission systems with DEF and DPF including pros and cons? It’s a reality that can’t be ignored in today’s modern diesel.

  6. Actually, it’s the EXPANSION ratio that wrings energy out of combustion. Have to figure in turbo or Power Recovery Turbine expansion, also. You COULD make a 30 to 1 spark engine and avoid detonation by using late intake valve closing and having short ‘effective’ compression ratio. Actually. in ’74 Hot Rod magazine put a kit in a 350 chevy and it was real fuel efficient but it knocked power WAY down. GM and SAAB experimented with variable compression ratios in the 80’s. It looks like newdesigns and computer controls made all that un-necessary.

  7. Please tell me why would you use a Powerstoke for the video when you could have used the Duramax engine. The Powerstoke is one of the worst diesel engines in the world and ford is horrible. GM FOR LIFE!

  8. the government is wasting money trying to make vehicles run cleaner. they should be trying to make the vehicles run for efficiently and a minimum should be 100mpg. that would make a bigger difference in emissions.

  9. diesel is better, no if and’s or but’s about it folks. don’t let anyone fool you…

  10. My buddy has 2012 ram 3500 and he straight piped it ha sounds good but he gave me the exhaust system to sell I saw that the cats are expensive where can I get rid of it at

  11. people do not know that diesel fumes are too heavy to go into the atmosphere, so they end up on the ground. while gasoline fumes are light enough to go into the atmosphere

  12. Nice video man even if it is ‘Diesel’ from an US perspective lol..Not many people in the UK/EU buy petrol engined vehicles any more. Diesel has almost 60% of the car market. Regards and like your pick up.

  13. Diesel noob here. If diesels don’t have throttle bodies, how does air get into the engine and how is it regulated? ie, if I put my foot down vs cruising?

  14. I like the way you said “new technologies, engineering and laws.” i don’t know, maybe i have a thing against laws. LOL.

  15. @ branden price…you are WRONG…..diesel engines were meant to run on peanut oil…check your facts MORON

  16. This video really helped me out. Ive always known a lot about truck and engines but some guys in my class started talking about some of the stuff in this video and I was lost…

  17. Wait I’m a 15 year old girl goin to school for diesel mechanics.. n i do have a issue with this video. If “diesels don’t have throttle bodies” air can’t get to the engine? And. It can’t be regulated .-. So done with this guy.

  18. I love the old clatter and smell of the traditional diesel. The new diesels have none of that. Very disappointing. Takes away the fun of driving one.

  19. Diesel engines have a similar intake setup as a gasoline engine, but they do not have/need a throttle body because diesel’s recieve the same amount of air flow whether they are at idle speed or full speed. Diesel engines change speed and power delivery by the amount of fuel that gets injected into the engine. The more fuel being injected, the higher the speed and power output. For example, when you accelerate in a diesel vehicle by pressing the gas pedal, you are actually simply changing the amount of fuel being delivered while the air flow remains the same. When the turbo charger ”kicks in” it forces more air into the engine so that even more fuel can be injected, therefor increasing power output. Make sense…?

  20. Very useful information, it is also kept very interesting. I learned a whole lot about diesel engines just from watching the video. I do love that Motroz shirt too, I’d wear something like that.

  21. I didn’t know this show excited Intel I found this video on YouTube. This video explained a lot for me thanks. I’m going to find the channel your on and dvr it. I thought it was a good show.

  22. RE air intake, I’m still a little confused. I understand that diesels always have the same amount of air flow to the cylinder (based on comments here), but what about stoichiometry? If you’re injecting more fuel into a cylinder, wouldn’t you need more air to compensate? I can’t imagine this being irrelevent for diesel engines, even without spark plugs surely they would need an optimum fuel to air ratio for combustion? Is air pumped in at a higher level, accelerant being the limiting factor? Surely that is inefficient, would the cylinder not have to overcome a higher pressure on the upstroke for no reason at lower RPM because there is extra air not being used? Or am I failing to understand something here?I’m far from a mechanic, but I’ve been working on my bikes for a few years so I know my way around a gasoline engine, but diesel is completely foreign to me. I recently bought a 4×4 so I’m trying to get my head around some of the basics before working on it.

  23. We all know that 4 stroke diesel and gas engines work pretty much the same way, but I’m still trying to figure out why 2 stroke gas doesn’t work the same way as 2 stroke diesel. I’m no engineer, but I think it would be possible. All you’d need is to add a cam, exhaust valve, bigger crankcase and a supercharger or turbocharge. It would make it heavier but it would still be powerful and it wouldn’t burn oil.

  24. are cars and trucks diesel engines the same ? apart from size ? MY 2002 W220 S320 CDI i want to upgrade some stuff will it make around 400bhp can it ? where can i get parts from ?

  25. Dear Chris,Thank you for the wonderful show, very informative ,wish you all the best and keep it up.RegardsHariBahrain

  26. A old diesel mechanic told me to put 1-2 gallons of gas in a diesel engine every 6 months and it actually helps the engine.

  27. In the UK and Europe now diesels have to be fitted with DPF cleaning filters and they are a complete nightmare. I don’t know what the score is in the USA but maybe it is worth covering

  28. This is a pretty good video! I’m getting a Diesel engine for my Triton Ute, also known as a L200, and i am getting it for the power output of the engine. Knowing they can run away, i have specifically said “I want a manual gear box” for in a few cases, It will give me more power when towing then a regular 3 speed automatic, and it will also allow for more control, such as a Diesel Run away event. The event being when the engine’s fuel is cut of, and starts using fuel from the Sump of the engine. Should the event happen, i can easily stop the vehicle engine, and avoid a melt down or worst. I also know, that in the event that i do such to stop the engine, it will need to be checked for Excessive damage to bearings and Gear box gears.The amount of power from the engine, could smash up some teeth within the gear box. And to avoid it, i will try and put other safe guards in-place, such as a air choke which is manual, and designed to regulate air from 0-100.

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