So I blew the rear end out in my k5 and I need to know what gear ratio is in an 88 k5 blazer it was the stock rear end. Any one who could help that would be great

 

There are Vin decoders that might tell you. Or you could make a mark on your drive shaft and spin the wheel one time. However many times the drive shaft rotates is your gear ratio. It won't be exact, but if it spins three and three quarter times, then you've got a 3.73:1. You could also take the gears out, count the teeth on the ring and on the pinion and divide them. That will give you the cast ratio.