I have a 5.3 in my 2000 Silverado rclb 4x4 and lately when i change my oil the drain plug end is covered in metal. (not piled up) but very noticeable. I change oil every 4-5k. i use all synthetic, royal purple mobil etc.. Should i be concerned? if so i have an extra 5.3 laying at my shop what budget builds do you think i should do for my dd? Im asking the pros here so give me some input plse. thank you