Rear from K1500 in C1500 axle questions

[RShrimp]

I have a 1990 C1500 with a rear end that will sing you a song everytime you get on or off the gas. I found a 1990 K1500 Rear end with 3.73 gears which would be my prefered ratio. It has 6 lug axles and of course I have 5 lug axles.
Can I just swap the axles and brake drums from my current rear end?
Can I buy axles with the proper spline count in 5 lug from like Rock Auto? (I know I can buy expensive custom ones)
If spline count is different can I just swap the side gears?
Will it bolt in and is it the same width?

Real question is What should I be looking for as a donor vehicle for a replacement rear end?

 

[b454rat]

Measure from the backing plate flange to flange of each. If there the same, then parts are interchangeable. If they aren't then you can't interchange em...

 

[FullBlowncustoms]

Not sure how my 89 C1500 was done, but it has the 3:73 gears in it. And 5 lug.

 

[97c1500ext]

I have a 1990 C1500 with a rear end that will sing you a song everytime you get on or off the gas. I found a 1990 K1500 Rear end with 3.73 gears which would be my prefered ratio. It has 6 lug axles and of course I have 5 lug axles.
Can I just swap the axles and brake drums from my current rear end?
Can I buy axles with the proper spline count in 5 lug from like Rock Auto? (I know I can buy expensive custom ones)
If spline count is different can I just swap the side gears?
Will it bolt in and is it the same width?

Im not sure about all the internals but i know that 4x4 rears are slightly wider than the 2wd rear and is not a direct swap. If you want a beefier rear people will tell you to look for a C2500 "light duty" rear from i think its like 89 to 93. Imo they are not as easy to find as some like to think, i guess it depends on where you are.

Id say just get your 8.5 rebuilt with a new 3.73 and add a nice posi to it while its apart.

 

[FullBlowncustoms]

Found this info... IDK if any is correct? My 89 is really QUICK.... But it hits 4th to soon. 700r4 in mine. UNLESS ??? mine is 4:10 gears? at about 68mph it is got some rev to it cruising...
https://www.67-72chevytrucks.com/vboard//showthread.php?t=628978

https://www.gmt400.com/threads/rear-end-interchange.58470/

 

[FullBlowncustoms]

If you do it, there are shims each side MAYBE.... take note the sides etc placement. Not knowing what you are doing? it is tricky first time rolling in the spiders, pin, etc... and MUST be lashed correctly... you can use a dye etc... done a few on older GM rears. Your pinion will also have a squish tube sleeve fitting to load.

 

[RShrimp]

Solved this problem. Found a Junk Yard 93 2wd with 3.73 gears for $300. Same yard also had all the Interior plastic I needed. I told what parts and he ask me what color I wanted. Im like, I can paint it but since your asking, I would prefer gray.

 

[someotherguy]

Solved this problem. Found a Junk Yard 93 2wd with 3.73 gears for $300. Same yard also had all the Interior plastic I needed. I told what parts and he ask me what color I wanted. Im like, I can paint it but since your asking, I would prefer gray.

This was the best path. The 4WD rear for your 2WD was a non-starter; different in every way that matters. Wrong width, wrong lug pattern.

Richard