I have a s10 blazer, 4.3 4 wheel drive with a 4L60E transmission. I lost 2nd gear over a year ago. I had a transmission shop look at it, they told me it was internal and would need rebuilt and that I shouldn't drive it anymore that way, that I would soon lose all gears. Over a year later every other gear is still running strong, even pulling a trailer a few times with 1000+ lbs in it. Are there any things i can check myself on it or will it need a rebuild?