Riddle me this...

Very simple to check rear end gear ratio. Jack rear wheels off the ground. Then put a mark on the drive shaft and a mark on the tire at the very bottom. Then turn the drive shat slowly until the wheel makes one full revolution (the mark will be back down at the bottom) while you are counting the revolutions of the drive shaft. So if the drive shaft turns 3.5 times to get the wheel to turn once, your ratio is about 3.5:1. Assuming the tranny is not slipping, I doubt you have 2.76 gears.