not sure if i already posted this or not, but my car supposedly has a 4l60 thing is i dont think i have overdrive as at 6 on the interstate i run about 4-4500 rpm and i only feel the trans shift 3 times when in gear, so guys is there something wrong with the trans or is my tach just wrong?

Bump* someone with any knowledge about it help? anyone?

unless it's been swapped you don't have a 4L60

get a cheap auto meter external tach or a timing light with tach and verify your rpm's

the stock tachs are junk

it was swapped, and i dont think the tach is right, theres no way its running 5 grand, i'd actually hear the flowmaster if it was, still though, i dont feel it shift more than twice