What's the difference between a D100 and a D150? Or a D200 vs a D250? I get half ton vs 3/4 ton but what does having or not having the extra 50 mean?

I do believe they came out in around 77, they have a heavier GVWR in order to meet heavy duty US federal emissions ratings.

May have been more related to trim levels, or it seemed that way on my 78 thru later eighties etc.

When the EPA handed out their rules (restrictions) for the D100 and W100, Chrysler started calling the trucks D150 and W150 to avoid the EPA regulations for a while so they had more time to meet their rules.

D 100/150 trucks are 1/2 ton 2wd.
W 100/150 trucks are 1/2 ton 4x4.
D200/250 are 3/4 ton 2x4
W200/250 are 3/4 ton 4x4
and so on.

The difference between a 100 and 150 is simply the year of manufacture. Ford became an F150, Dodge followed suit. GM jumped from 10 to 1500, and Dodge followed that (later).

My 75 W100 was the heavier version, technically it was a W150. It had a 6100 gvw, so that way it didn't have to have any emissions equipment on it. Mine had no egr valve, sealed fuel system, etc.

Many years they made both the 100 and 150.

This is true. I have a '82 D150 and a '84 D100.

The difference is GVW rating.
In the mid '70s, catalytic convertors were required on trucks if they were under a certain GVW. Bumping the GVW up on a D100 to a new D150 model exempted the need for a CC.
Eventually the CC requirement GVW was raised over the years. The last year the D150 was exempt was 1978, '79 150s had CCs. The D250 and 350 exemption went into the '80s. I had a '84 D350 that came without CCs.

Had an 89 w350, factory non cat. Dual smog pumps though.

ITS 4X2---- a 2x4 IS A PIECE OF LUMBER

In the beginning the 00 were the base rating/component trucks, the 50 were the HD version of that series meaning Bigger Alt, Trans, Fuel tank, Radiator, Diff, tires and payload just to some of the upgrades. As the series number got bigger the upgrades also included frame construction (taller, thicker and even double walled)
eventually they dropped the 00 and just added HD packages. This was a manufacturing cost savings ( brochures, emblems ect...) and also led the less informed consumer assume all trucks were equal
and I just remembered here is the ratings "in the beginning"
D/W 100 = 1/4 ton
D/w150 = 1/2 ton
D/w200 = 3/4 ton
D/W 300 = 1 ton
The 250 and 350 badging didn't start till mid to late 70's
for example I owned a '74 D300 with a 10000lb GVW
and a 83 D350 with a 8750 GVW

The 1st year of the D150 was 1977. I had one with the 8 3/8 rear axle from the factory. There were D100s with the 9.25. The same transmission was available in both, fuel tank sizes were not dependent on truck weight, alternators were optional, the same spring capacities were available on the D100 and D150, tires and wheels were the same size, the frames were the same, etc.

From the brochure:
*All D100 models include Evaporative and Exhaust Emission Control System. All D150,D200 and D300 models include heavy-duty Exhaust Emission Control System.

GM went from 10 to 15

only the d-150 came with big block

Not so sure about that. Buddy of mine had a 78 W300 with a 440. He ordered it new, kept it till he passed away about 7 years ago.

Always garage kept, wish I had it.

I presume he meant the D100 couldn't be purchased with a BB but the rest could.

I read somewhere that the 100 models were lightweight (as far as carrying and towing capacity) versions that were subject to stringent emissions (catalytic converters, etc) whereas the 150 models were considered a "heavy half-ton" and were not required to have as many emission controls. Additionally, the 150 models may have had a few goodies not available on the more basic 100 models.

My D100 was my grandfather's and it's as basic as they came; the only option it has is carpet. The D150s also had slant sixes as the base powerplant, but they must've had better springs or something because my D100 wallows like a hippo on a slip-n-slide when I tru to carry more than a couple sacks of fertilizer.

What years are you referring to?

I had a 67 D100 that had a 383 and have seen many Sweptlines so equipped.

Kevin

My bad meant difference in 100 and150.and yes there was a special package 100 with 383 but couldn't get a 440.of course 3/4 ton and up could b had with big block

If you mean a CSS, mine was just a custom cab D100. No CSS.

There is a 70 or 71 D100 local to me that is a 383/727 with A/C and power steering.

Kevin