My trip to the car wash was reasonably successful. Unlike my last build
"Refining Sierra" The leaks on this truck are fairly new and haven't been baked on so badly. The engine cleaner did a pretty good job. At least good enough for me to see exactly where the leaks are coming from.
Since this truck didn't come with a paper trail on maintenance, I decided to start from the back and work my way forward servicing everything along the way. This would allow me to honestly and accurately know the condition of the truck for future reference.
My first stop was at the rear differential. I know its a stock GM 10 bolt, and I assumed it was an open carrier with 2.56 gears. I determined that to be correct when I pulled the cover. I could tell that the rear had been serviced before, but the condition of the 90W told me it had been quite some time ago.
I thoroughly drained the rear, flushed it out with Brake-Kleen and wiped it dry. Fortunately the snout was not leaky, so no need to replace the pinion seal. The positive side of this is it does have the optional HD 2.375" drum brakes. The negative side is one of the wheel cylinders is seeping.
An hour with a wire wheel got all the caked on red clay off of the housing, combined with a trip to the blasting cabinet and the cover and drums ready for paint.