Q: Which diesel is most superior? 7.3 5.9 6.6

asked by on January 19, 2017

I want to know from a random diesel enthusiast or mechanic which diesel truck do you think is the best all around made. In terms of least problems and cheapest fixes (when things go wrong) between the 7.3,5.9(2nd gen),6.6(LLY) and I know everyone has there own opinion but I want yours. Thank you so much, I currently own a 5.9 and I love the truck, I'm just not sure if it's the better diesel of the 3. Apart from tranny problems and the fuel system I'm throwing money away. Which diesel from stock is the best all around, thanks!

The 5.9L diesel is a straight six engine. The 6.6L diesel and the 7.3L diesel are both V8 engines. If find that there are more maintenance when it comes to the V-configured engines to the straight six engines. I have worked on many straight six diesel engines and many V8 diesel engines over my career. Most vehicles with the straight six engines are usually having problems with the fuel filters and the fuel injection pumps. The V8 diesel engines tend to have multiple issues with the turbos, the waste gate controls, and tend to have issues with the engine performance with the glow plug circuits. I recommend staying with what you have unless you are wanting to go up in power and have more torque. I have seen a Dodge Cummins Turbo Diesel 24 valve put out 1200 foot pounds of torque and have over 600 horse power from stock settings with a smart box to change the pyrometer controls. A straight six engine is more comfortable in adjusting performance than a V-configuration engine.

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