While I'm driving my 6 speed( manuel trans )sentra
at about 60 to 75 and want to to speed up I'll see
the rpm's jump but my speed doesn't really change,
so I thought maybe shift down and see if that's
what I should do but the same thing happens,
what's wrong with my car??
Sounds like a slipping clutch-- you will likely need a new clutch assembly!
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