I need some help here!My wifes truck(tahoe) needed a new brake light switch,replaced it,and now 3 days later,I go and start the truck,it starts,i notice that the brake lights wouldn't go on,and to top it off, the truck won't go into gear.I checked fuses(good),could this be a relay problem?I need help,I am tired of paying mechanics to tell me I DON'T KNOW!!!!Thanks

If it won't go into gear and the brake lights aren't coming on, it sounds like the switch went bad again. Something else is causing the bad switch, if that's the case.

Unfortunately, sometimes this is how the process of elimination goes. Call them and ask them about it and see what they say. Perhaps the tech can give you an idea of what it could be that's causing it to keep going bad, that is, if it is, in fact, the switch again.