I need some help decoding an axle

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DanMcG

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This is the original vehicle inspection sheet from my 78 K10.
Does anyone know how to read the Axle number listed, or a link to where I can find the info?
I haven't had much luck finding info.

And if anyone wants to have a guess at the trans number I'd appreciate it.

Thanks

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Axle # forth row down, sorry for the sideways pic.
 

DanMcG

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Could the Axle # posted be off the tag on the cover? and what about the engine #? The tranny makes sense after some more research.
 

DanMcG

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Thanks HotRod, I'm not sure why I didn't look there to begin with. :shrug:
 

Honky Kong jr

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I’m gonna guess 3.42:1 gear ratio based on info provided




I can feel a slap already.........lol
 

HotRodPC

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Honky Kong jr

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What is this W82??? :shrug: It's not an axle code.
Not an RPO I believe it’s stamped on the tube. OP what does the build sticker say? The one with the RPO codes say. @Keith Seymore could surely assist in this matter.
 

HotRodPC

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If the axle is factory and he got the 3 digit code off the tube, it will tell us what it is, but that's not an axle code. Usually 3 letters.
 

Honky Kong jr

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If the axle is factory and he got the 3 digit code off the tube, it will tell us what it is, but that's not an axle code. Usually 3 letters.
That page appears to be a PDI check sheet so who knows where it came from.
 

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Retro complied all those codes. So far they've been accureate for the 10-12 codes I've looked up.
 

Keith Seymore

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In this specific case "W82" doesn't really look like an axle broadcast code and does not fall in the family of rear axle RPO codes (unless it is an SEO code (a "Specialty Equipment Code", which is an option that is available for Medium Duty or low volume vehicles but not normally available on regular production vehicles).

Besides - since the tag has the numbers "342" on it I'm thinking it is telling you it has a 3.42:1 axle ratio.

If you want to dig further you can report back what your SPID label says on it, or give us additional detail about the engine, trans and GVW rating and we can pull the powertrain charts and tell you what was base and what was available optionally.

What is it that you are trying to figure out, that is not already known?

K
 
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DanMcG

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What is it that you are trying to figure out, that is not already known?

K

Thanks for all the input people. I started the post because I searched for info on axle codes with no luck until HR showed me the link. I was just researching the trucks history and after getting stumped by the engine number, which I still am, I moved on to the rear end number. I'm just trying to learn more about the truck and square bodys in general.
As far as the SPI goes, there is no differential listed. it came with a LF4 400ci 4 barrel and a MX1 Auto trans. the power train chart shows the standard ratio is 3.07. the truck is a 78 k10 cheyenne, build date is Dec 18 77. would the cheyenne package bump the gears up?
 
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HotRodPC

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So there's NO RPO codes that start with letter G? Normally most codes related to the axles will start with G. Sometimes you might even have 2 G codes. 1 will be the ratio and 1 will be an optional locking diff or LSD which is usally G80.
 

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