You can test the center bearing just like you would test any other sealed ball bearing. Free the carrier from the car body by removing the bolts. Check for excessive play and check to see if it rolls smoothly. If you can "feel" the balls moving around then it time to replace it. I always inject some grease into them using a syringe and hypodermic needle.
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I got too many cars!! Insurance eats me alive. Dave
78 Corvette Stingray - 3k
82 242 Turbo Volvo - Manual - 270k
86 300e 5 speed manual - 210k
87 420sel - 240k
89 560sl - 78k
91 420sel - 205k
91 560sel - 85k
94 GMC Suburban - 90k
97 Harley Davidson Heritage Softail - 25k
00 GMC Silverado 1 ton 30k
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