Can anybody identify this turtle?????

Plus they grow to 6 ft in diameter.....

Only snappers grow that large. However the largest I've ever caught wat 4 and a half.

Depending on where you live, that may be a stinkpot turtle. I don't have any experience with stinkpots, but do know that they live down south.
 
It's not a mud turtle, it's not a snapper it's not a red eared slider. It's already been identified as a Stinkpot. I know this because I own two of them. They also have a very large home range in the east that stretches from southern Canada to the tip of Florida.
 
Yes...the link provided was to alligator snapping turtles, which get significanlty larger than common snappers. Allys still only get 20-24" SCL on average though; although there are some exceptions, I highly doubt 54" is one of them.
 
AquariaCentral.com