My inspection failed on my '96 Blazer for a number of reasons including replacing rear axle seals. There is no obvious sign of fluid on the differential housing. How did the mechanic make this diagnosis?

 

must have had the wheels off to see, cheapest way to fix this is to get brake cleans and spray if off clean it up and take it back for inspection. also pending on how bad the leak is the inside of the rim could be wet or its running out of the brake drum/rotor in that case the seal needs to be replaced but if its just sweating than iwould just wash it down.

 

There was some fluid on one rotor, but could it be brake fluid from a bad wheel cylinder? I just changed both cylinders. I'm going to clean up the brakes as you suggest and then see how it looks after driving a while.

When you say sweating, what do you mean and where would I see that?

Also is there any lubrication of the hub bearings to do while the wheels are off? Nothing has been done on this truck for a long time. I know I probably should replace the seals and bearings regardless. My time and funds are just about out.