I have a 2002 blazer that runs fine in 2wd but when i put it in 4hi or 4 low it makes a loud clunking noise and the faster i go the faster it goes. sound likes it's on the right hand side ...this was the first time i used 4lo. when using 4 hi before it did not do it but now it does it in both. I'm not very mecanicly good so i would really appreacite any help