Looking to replace the rear-end in my 87. I have a cousin that may have one , but it's in a 90 Suburban. If the gear ratio is the same would it work alright?

 

It depends. Is your Silverado 2wd or 4wd? With 2wd, your rear doesn't have to mesh with a transfer case, so it's not as critical.If it's 2wd, you could even get away with another gear ratio. If it's 4wd, it's a whole different ball game. A local salvage yard has interchange manuals, and would probably know if the differentials in question are similar.

 

the most important thing is the spring center locations on both axle's and wheel bolt circle's ,and u-joint sizes .

 

It is 4wd. But gonna have to look somwhere else, cause the Suburban is not a junker like I was hoping. My cousin heard that a 12 bolt will work also, just as long as the gear ratio is the same, but I'm not sure on that. I know that the gear ratio has to be the same just wondering what my options are?

 

Try ChucksChevytruckpages.com for info which will narrow down your search. Or google "1987 Silverado axle ratios" Once you identify your ratio properly, you've got 4x4 shops,parts stores, the net, and salvage yards for starters.