I also lost first gear. A friend called Nissan and they told him that this was common for 2000. They made two transmissions in 2000 and one of them was made of not as hard a steal. They corrected the problem in 2001. Although my Nissan dealership said they had never heard of this before and were shocked I lost first gear. I no longer trust them. I took it to Mister Transmission to repair. Quite costly but it needed to be done. Can't keep starting in second, then you will wear out second. They replaced the sinchro, clutch and machined the fly wheel. I had the clutch replaced as it's 6 years old and 150 km. they said it was more than 50% worn and since I plan on keeping the truck it was wise to replace it at the same time.