Every time i shift at highspeed 70 mph from 3rd to 4th it grinding carzy but not down shifting(5th to 4th)some time 1st (stop motion) and high speed 5th.

well, The only thing i avoid this is double clutching from 3rd to 4th sometime tripppe clutching. i think it the clutch drag. Do i have to change the clutch to fix this or change my trans or take this to dealer??? I am not should the dealer going to cover it.
Mod:
up pipe
downpipe
bov
intake
cat-back
hid
custom projector head light
turbo timer
boost gauge

 

maybe u should hold the clutch in b4 switching gears

 

It sounds like your clutch may not be disengaging completely. This may seem like an obvious thing but when you shift do you depress the clutch pedal all the way to the floor?

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0==WW==0
"…axles of evil…" - george w. bush

 

How many miles on the car? Did you learn to drive on this car as well? Is it a used car?

 

47000 mils yes i kind of learn to drive from this car it was band new.
i am thinking may be the polit bearing or fly wheel sucface or clutch disc bc i just notic it only grind when after warm up