Not sure if this the correct forum but the site wont let me post anywhere else. I recently hit 160k miles on my 2003 nissan frontier XE v6 3.3l RWD automagic transmission. I am under the impression something is wrong with my rear differential. I park on the street which faces uphill. When I start the truck and shift into drive and depress the gas pedal the truck will roll backward 3 or 4 feet before it Jerks and drives forward. I also notice after accelerating sometimes when but not every time I can hear a grinding noise coming from the rear of the truck that last for a second or two. Am I spot on or is there something else at play?