I have a 2012 Sierra SLT 1500, started with 4" BDS lift but added two more inches to clear 35 x12.5" still had to cut a bit on the front to eliminate rub. I love my truck but two times out on a great crawling trail had to finish in two wheel drive. First time my front diff shattered, my fault for going a little quick but this last time I broke a CV axle at low speed trying to go up a rock. Are there stronger parts available? The diff especially is my concern, the piece that broke was made of aluminum and I can't find anything about upgraded parts.