so i took my 2010 silverado to my dealership where i bought it, and they told me my rear pinion seal that is leaking is normal. also i have a rough country 5 inch lift on it, and they told me it voided my warranty, so they wont fix my from passenger axle boot that is leaking grease, when i know for a fact that the lift lowerd the front differential so it would still have the factor specs. so why is my warranty void. i think they just dont want to fix it. help?