305 SBC vs 6.2 Detroit: Which would you rather?

Which Engine?

  • 305 SBC

    Votes: 14 38.9%
  • 6.2 Detroit

    Votes: 22 61.1%

  • Total voters
    36

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CheemsK1500

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A common recurring theme I have noticed, is that the 305 SBC and 6.2 Detroit seem to be hated, even though general consensus deems them both reliable options. Assuming you are given a choice between two trucks that are identical in every regard except for the engine (One has a 6.2 Detroit and the other has a 305 SBC), which are you choosing?

ETA: You are not allowed to perform engine swaps in this scenario.
 
Last edited:

mcarlo86

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Full disclosure: I have a '90 K2500 with a 6.2....so there is that. But I guess if you had to pick between the two, I tend to think if you are settling for an engine that doesn't make much power, at least the 6.2 is pretty fuel efficient.
 

Goldie Driver

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I voted 6.2. I drove ( in the mid to late 80s) a mid 80s Blazer that a buddies Dad owned with a 6.2 and enjoyed the mileage, what seemed at the time as reasonable power, and smoking people at idle with neutral revs.:anitoof:

Same guys Dad had a mid 80s K10 with a 305 that hauled ass, so maybe they just had luck.

Anyhow, I have never owned an oil burner so that's my logic tonight. :)
 

mxer147

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6.2, diesel’s are awesome, way more to work with to improve it. However, I wouldn’t waste my time driving it during the winter season especially the very cold days. Working at the dealership in the 80s, we would tow the diesel into the shop rather than trying to get them started out in the cold. Gratefully, my 04 Duramax doesn’t include that trait.
 

squaredeal91

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All jokes aside I like them both but find the 6.2 more usefull and up my alley but I've had good experience with 305s and I know there not bad. They just both inherited a bad wrap for some reason. I've heard the same about 700R4s but think it's bs. That's my buck 05 worth. Lol
 

Strick

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Give me the Detroit with an SM465 all day long! Real trucks have a clutch pedal and no spark plugs… (here comes the hate messages)!

Strickland
 

Soundmound

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I'd prefer the diesel milage and torque but would take the 305 because I can do my own maintenance on it. My 84 is a 305/700R4 combo, but was purchased primarily for its color combo and rust free nature, also not needing paint and body at all.
 

Trucksareforwork

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Never driven a 6.2 so I can’t vote, but my take is the 305 gets a really bad rap because folks pull all the stuff necessary for it to run well. My 305 from ‘85 starts great and runs great as an around town or highway rig. Only issue I get is pinging when loaded down and running 89 or less octane. Thats because I have no esc.

The older 305s are better than mine because they are lower compression.
 

1x1_Speed_Craig

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6.2L diesel
I own an '86 M1008 with the 6.2L diesel (35K miles), and an '85 M1028/C-10 project truck that'll be getting a 305.

The 6.2 is a dog, but I don't mind that. For me, the truck is primarily used as an around-town truck (30-50 mph speed limits) and somewhat of a beater farm truck. I'm consistently getting 16.5-17 mpg, which is pretty respectable for a 1.25-ton truck, IMHO.

That said, when I first got the truck 7 months ago, I checked with several local diesel shops to see if they'd just do a basic "health check" on my new truck to look for any glaring maintenance issues/considerations, and had shop after shop tell me they won't even work on them, as parts availability and prices are tough. I get that, but I was just looking for a basic mechanical inspection. Still, no go. I finally did find one shop to look at it, but that was 6-7 shops after I started looking, most of which were diesel-specific shops.

My 6.2L now has a Fluidampr and some new pulleys (which has gotten rid of my previous belt tension issues), new belts, new CDR valve & oil cap, etc. and it's no longer a "ticking time bomb" with the OEM harmonic balancer.

So I do like the 6.2L, but don't know if I'd buy another (at least non-military) truck with that engine. If I was still making my own biodiesel fuel, which I did back several years ago in the Obama/$4+ per gallon fuel days, I'd obviously be biased towards the 6.2L for that reason alone.

The 305 may be a bit of a dog, too, but it's at least better supported than the 6.2L.

That's my $0.02...worth what you paid for it.
Craig
 

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