Living here in the rust belt of Pennsylvania I have a lot of scale that is flaking off the transfer case and some on the Getrag transmission. I am looking at using my pressure pot sandblaster to do the descaling of both units bolted together along with the bellhousing attached. Aside from the obvious hose connections to the vents, drive shaft yoke u-joint surfaces, Getrag shifter, and the transmission input shaft, are there any other areas that need sealed off or will require anything special for protection? I don't want to be shooting q-rock sand into the cases...Anybody out there done this before?

 

i would run a strip of duct tape around the seals surfaces, just to be safe! That sand has a way of finding it's way into crevices, especially when under pressure....

 

I think I would try something else, Maybe a high pressure washer would work.

 

purple power degreaser and a pressure washer will do wonders.

 

I would try not to sandblast it. Powerwashing is a much better option. Maybe powerwash it and paint it an aluminum color if that is was you are after.

 

I sandbasted a Oliver tractor when I was restoring it. NEVER again will I sandblast anything like axles, motors, trannys again. The sand did find its way in and it took gallons of diesel fuel to flush the grit out.

 

So far I used a welding chipping hammer to remove the rust which resembles layered welding slag about .040" thick. I need to get down to the base metal in all the nooks and crannies before any paint goes on, otherwise it's just going to keep on scaling even with new paint. The pressure washer isn't going to work because it takes a fair amount of effort in some places using the chipping hammer. I looked at using a phosphoric acid based cleaner but it has a tendency to creep into the slag and then continue working under the paint. The transfer case is far worse than transmission. I'm trying to avoid the time and costs involved on dismantling both pieces as they both ran perfectly in the truck. This setup came from a donor truck that had a snow plow and spent a lot of time on salted Pennsylvania roads. So warning folks, don't put a snow plow on the front of your truck unless you intend on sacrificing it to the salted roads.