The Legendary Slant Six

The Legendary Slant Six


Few engines can truly claim the status of legend, but the Slant Six, used in Dodge vehicles from 1960 to 1987, is one of them. Some old garage hands say that if it was properly cared for, a good old Slant Six might just run forever.


A clean-sheet-of-paper design, the Slant Six originally took its name from its innovative cylinder layout—the block was laid over on its side 30 degrees to the right to allow a low center of gravity and a low, sleek hood profile to accommodate the futuristic body styling of the era. Many of the features of the Slant Six were equally unique and advanced: chromium piston rings, ram-tuned manifolds, and even a die-cast aluminum block on some models. Engineers reported 20 percent more power for the Slant Six compared to the previous six-cylinder engine, with a 15 percent gain in fuel economy as well.


Over the years, the Slant Six was produced in 170-, 198-, and 225-cubic-inch versions for use in both Dodge and Plymouth vehicles. Due to the engine’s almost indestructible nature, it was also a popular choice for agricultural, marine, and industrial applications. Introduced on the 1960 Dodge car line, the Slant Six remained in production for passenger car use until 1983, and in trucks until 1987—an amazing 27 years, more than a quarter of a century.


In fact, the Slant Six proved to be so durable and reliable that even as the 21st century began, replacement engines and parts were still being manufactured in Mexico for heavy-duty use in emerging markets around the world. Few mass-produced goods can claim such amazing longevity. Many Dodge owners still look back fondly today at their first cars powered by Slant Six engines that just wouldn’t quit. It’s part of the Dodge brand’s reputation for quality that stands to this day.


  • epicurus

    A great engine. Growing up I had several friends who’s parents had the 225 versions in both cars and farm trucks. They went forever.

  • Paulie

    They forgot the Hemi race version made in New Zealand. You can still get them too.

    • Dave M

      I think you’re confusing the Australian “Hemi’ 6 with the slant 6. No relationship whatsoever. Conventional upright , water pump at front of block, 7 mains, canted valve, larger bore centres. Production ceased 1983.

  • Sam

    Great engine! I had one that blew a cylinder and put a 4 in dia. hole in the motor. still drove the car 5 miles home.

    • john

      had one that through 2 rods through the side of the block i drove it home

  • Mark

    Had a few 225′smyself. 1979 Dodge pickup converted to a flatbed 904 tourqueflite with a shift kit, ported the head and intake with a holley 2 barrel. Also had one in a 81Chrysler lebaron i paid 75 bucks for,tuneup,rebuilt the spent rearend,and the carb and drove it forever! Ran quiet as mouse. The mopar performance catalog had performance bracket racer parts for them. Great engine.

  • Eric

    bottom line bullit proof less you got the lifters too tight and compressed 1. but was easy to fix with the side boxes

  • McLaren302

    I currently own a 1976 Plymouth Scamp with a 225 slant-6. It doesn’t have enough power for what I want, so unfortunately it must go. A a hand-rebuilt 318 with Hughes Engines Whiplash cam will take it’s place with great humility.

  • Mike

    i have one in my first car, a 1969 dodge dart that dad gave me for my 17th birthday…im 22 now. the car had 453,000 miles on it when i got it, ive put on another 50-60,000 , do the math…its indestructible, i wish chrysler would bring these back..hopefully the way it used to be, i tried the new dodge dart, its peppy, but its just a re-shelled fiat 500…its horrible…

  • Gary Smith

    Well the slant six was an Icon Motor, But I put my AMC strait 6 258 up on some runs against v’8s and took em on start

  • cjleete

    An updated slant 6 maybe in the 4 liter range with overhead cams and direct injection with today’s engine management tech? Done right it would dominate Ford’s Ecoboost offering and give us a more economical option for Ram and Durango, while giving more torque than the current V6 option.

    • cjleete


    • Sam

      I couldn’t agree with this any more!

  • Tommy Lovati

    I’m sporting a 1968 Dodge Coronet Deluxe with a Slant 6 in it and won’t change it, 23 mpg ..

    • Cp

      Mostly Highway I guess. Getting something similar here with a 69 Charger Slant Six, 2.73 Rear End Gear Ratio.

      • ReformSchool

        I would think a 2.73 final-drive ratio in a car would do better. Before U.S. regular gasoline was diluted corn oil, and Regular grade was an honest 89 octane, my 1966 A100 van with 2.9 liter (170 c.i.d) moving an 800 lb.payload with HR78-15 snow tires, 3-speed manual gearbox, and locked 3.91:1 Spicer 50 rear consistently delivered 20 mpg highway AND CITY, 1982 – 1991. Santa’s annual polar reindeer games had nothing on Dodge’s daily Mopar SlantSix games. The only other spark-ignited highway motors I ever saw with comparable durability were Mopar 413-2 & 413-3. Combining tall cam with long stroke gives gobs of torque at low r.p.m. Low rpm over long periods provides fuel efficiency and long life. The John Deere Model B tractor was such an animal.

  • Cuda340

    I bought a 1963 Plymouth Belvedere in 1967 as my first car with 51,000 miles. The previous owner never changed the oil and the oil passages were partially clogged. After cleaning them out, this indestructible engine ran for another 40,000 miles until I sold the car in 1971.

  • Michael Marr

    Put this engine into manufacture ASAP, please.

  • Richard Ell

    I owned two 225 Slant Sixes – one, a 1969 Barracuda, the other – a 1972 Dodge Dart. I consistently got 18 mpg, no matter what I did (highway or city). Neither engine EVER broke down on me, nor even threatened to. Must have put a total of about 120K on those two engines (bought both cars old and used). UTTERLY RELIABLE. Both were 3-speed automatic transmissions, acceleration adequate but unexciting. I regretted selling both cars. To this day, I wish I had kept the Barracuda.

  • hunt58

    I have a 1968 Plymouth Barracuda notchback with that 225 slant 6 original motor 68000 milesI’m debating on pulling the slant six and putting a 340I don’t know if it’s the right thing to do matching motor matching car

  • Daniel

    Dad bought a 67 Dart with the Slant 6. Went through it, fluids, filters, tune up. 7 years and about 80k++++ miles, with no other routine maintenace done…car refused to die. Sold it to his cousin, he did the same initial maintenance, drove it for another 5 years. Sold it to buy a new Tercel…had more issues with the Tercel than either family had with the Dart (which was none). Unbelieveably unbreakable engines.

    My family has owned around 8-10 Slant 6 vehicles, one more amazingly reliable and unbreakable than the next.

  • bambamteddy

    I found a early cuda w slant six super 225 in how can I tell the year of it. Ruff shape wants 950 for it. Rusted out parts of bottom rear wheel wells. Pls help

  • vanman2

    im Driving a 1965 Dodge A100 panel van SL6 3 on the tree i love it , always been a SL6 guy !!

    • nemosfate

      I’ve got a 67 valiant with the 3 on the tree and slant six as my daily driver

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  • DAW3

    You got that right! I (daily) drive a 1964 Dart GT with 300K on it, and I have no doubt I’ll see a Million Miles on it someday! I own a Zippo lighter too!

  • Nick

    What they should do is
    A: Make the engine even MORE indestructible
    B: Make the engine create more power
    C: Make the engine even more affordable as the years go