1. My Trailblazer whined like a misbehaving two-year-old until I flushed the old PS fluid and installed Genuine GM "Cold Climate" PS fluid. If whining isn't a problem, regular plain ol' PS fluid is fine. Available from GM, or from every parts store in North America.
2. Pull the fill plug on the front differential. If it leaks, it's low. They don't hold much, so it doesn't take much of a leak to run it dry. Dry bearings and gears don't last long when you use 4WD. I spent about two years dicking with my front differential because I was too lazy to replace the right-side seal. Every 300 miles, I had to pump more 75W-90 synthetic fluid into it. DO NOT let it run dry.
3. If the differential fluid is still reasonably full...the leak is from somewhere else.
2. Pull the fill plug on the front differential. If it leaks, it's low. They don't hold much, so it doesn't take much of a leak to run it dry. Dry bearings and gears don't last long when you use 4WD. I spent about two years dicking with my front differential because I was too lazy to replace the right-side seal. Every 300 miles, I had to pump more 75W-90 synthetic fluid into it. DO NOT let it run dry.
3. If the differential fluid is still reasonably full...the leak is from somewhere else.
