Chevrolet Repair: 1993 Blazer K1500 Shuddering, k1500 blazer, independant shop

Question
I have a 93 K1500 Blazer and just had a posit traction rear dif put in...since then I have been having shuddering happen to the vehicle at 50-60 mph. My mechanic added shudder stop to the transmission and it did slow it down, but now I have hi rpm when accelerating but with loss of power. It feels very sluggish and I am afraid I might need a new tranny...

Answer
It does sound like an internal trans problem to me.  Usually a shudder will be the reaction shell inside, or the sprague gear bearing starting to lock up and will do a tom of more damage if left unfixed.  With the high mileage you may have you will need to ask yourself if it is more cost effective to replace, or rebuild.  Some places rebuild and give a 12 moth 12000 mile warranty, as if they replace you will get a 36 month 36000 mile warranty, so if you plan on keeping the truck, you will need to ask yourself which is better.  To rebuild at  an independant shop is usually about 7-800 bucks, where a replace is about 1800-2000 dollars
Jimmy