New beauty, NEED HELP!

[NewSquare]

Hey guys, first post, need your expertise! Quick 2 sentence back story. Grew up with a "big ol' chevy in the driveway." finally bought the one I have been searching for with a blown rear end. I picked up a 87 k30 454FI single rear wheel, with a "blown rear end." question were all the gear ratios in these trucks the same? If not how do I figure out what the gear ratio was in the rear axle, considering the previous owner cleaned out the banjo in order to move the truck across the yard in 4 wheel??? Please help any question I can answer off hand I will thanks guys, I'll post pics of the "burgundy beauty" soon as she's done.

 

[Irishman999]

I could be wrong here but I seem to remember a spread sheet in my glove box that listed all the options like gear ratio's, engine and transmission codes. If it comes down to it just jack up the front axle and turn the tire and count the revolutions of the driveline.

 

[RetroC10Sport]

Welcome. There were 3 ratios available in the 1987 K30.

RPO GT4: 3.73
RPO GT5: 4.10
RPO HC4: 4.56

If the SPID lable isn't in the glovebox, there are a couple of other ways you can check. One is take the cover off the front diff and see what the teeth are. Two is check for the axle code which I think is on the passenger side axle tube on the front.

 

[HotRodPC]

4:10 was the most common? Are you 100% its the rear end? Do you know how hard it is to kill a 14bolt Full Floater rear end? What do you mean blown? Explain. I guess it's possible someone didn't replace axle seals or pinion leak and let it run dry or something, but honestly, I've heard of a 14b getting noisy, and I know of a monster truck that shredded one, but past that, you can hardly kill one.

 

[NewSquare]

Thanks for those codes I'll definitely check those axle tubes. And hotrod to answer your question I work for a tow truck company been dropping off to this mechanics lot for about a year now, always drooled over the truck. Apparently the truck has been used for the past 11 years just to plow his lot, he said he pulled off the rear banjo and the gears were all pieces. Hence why with out jacking up the rear and spinning I was unsure how to check it.