I found a 8.5" 10 bolt with 3.42 posi with drums and leaf springs locally for $200. It's the factory GM parts so what should I look for to make sure it would run good?

he also pulled the cover to check the gear ratio

 

Tough one, because if we have to tell you what to check, then we have to assume you'll know a good wear pattern from a bad one.
Check the gears for unusual wear patterns, scoring, chipped or damaged teeth. The ring and pinion gears come as a set. If one of them is damaged, out of specs, or worn both must be replaced. When a vehicle pulls a heavy load the pinion gear tends to ride on the outer portion of the ring gear. This will cause excessive scoring evident on the outer edges of the ring gear.

 

Well its got to be firm and have a nice apple shape..... oh crap wrong forum.

 

^^haha true that

well i got the rear end for only 160 and it came with z28 leaf springs, drums and even 2 wheels and tires

 

damn it! i forgot to check the ratio when i got it. i checked for posi just not the gears. i just checked and its not 3.42 posi, its 3.08 posi

 

sounds like a T/A rear end. They had taller gears because of the low end torque of 400/403s.

 

well he said it was supposed to be from a 81 Z 4 speed camaro so it would have 3.42's but it's only a 3.08 posi. it's alot better than my 2.56's that i have now but i don't know if I should just sell it or just use it for now

 

When you put the BB in it will be a blast with 3.08s. It would be better with the 3.42s but the BB will have so much grunt you won't notice.

 

Considering the price I'd run it until the BBC is in, then decide if you want to change gears. Either way, I'd still keep it and use it.

 

so you think 160 is still good for a drum to drum 10 bolt with 3.08 posi? Yeah im thinking of just keeping it and running it til i get the big block then im putting in 3.73's since im getting an 4L80 trans