[BRUTAL]

you need to find and print info, past complaints brought up about this etc and talk to the regional parts and service manager. Youll need his contact info from either Nissan or the service manager, if they give it to you. I would ask for it to be goodwilled as unless its a definitive parts failure, or in some cases Ive seen 2 xs bolts loosing up the clutch pressure plate where it attaches to flywheel\, and flywheel bolts to crank. These were covered under warranty, but you desciption is generally not in the "part failure" catagory but in the "abuse" catagory. wether purposful, or from letter little brother/sister "learn" how to drive a stick. If you signed the repair order or write up sheet that theyre supposed to get every customer to sign when leaving any car for work, you gave consent and this includes both written and verbal per phone conversations. Laws vary state to state but this is the general situation with any shop. And you have to pretty much pull the trans to inspect the clutch to diagnose a fault and to determine either customer pay or warranty. The only time this "wear" item would be covered without much fuss is under the adjustment priod when adjustments or replacement of normal wear item are covered under warranty is usually a 6month 6000miles, or 12/12. premature brake pad, tire and clutch wear and alignments are usually all covered under this period, but it varies. So remeber to be calm, stae facts with written backup, and ask for their help without demands are your best bets