posi or no

[jojoman]

i just took my rear end apart because i was driving and when i hit the brakes my truck was making this rumble noise in back shaking my bed well i thought it was my brakes nope my seal from the axles were worn out and the oil from the rear end got in my drums and making it my pads stick and not braking had to take everything apart well after all that my bro told me my rear end wasnt a posi so just wondering is it or not is a 10 bolt my truck a 87 so just let me know