Frame Differences 350L 350M

[Kilian]

I brought home a K20 frame today from the mid 80s and when I checked the PNs for the frame rails I found that they are for 85-87 trucks with 350L engine (maybe others as well). I also noticed in the parts book that there were different frame rails for 85-87 trucks with 350M engines. What would have been the differences between the frames, both with 350s?

 

[Blue Ox]

K20s came in two versions. The heavier version was the C6P which used thicker steel. So, whichever 350 is the heavy duty version would have the heavier frame.

There's a more involved discussion of frames here:

Revisiting K10 vs K20 vs K30 frame specs.

Hello Gents! Its been a while since I've posted anything but this topic has been eating at me for a long time and since I could not Google a exact answer (contradicting answers every page I found), I assume others would like to hear what I have found. I also apologize if this has been answered...

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