Perfect, both of your responses tell me what I needed to know and how to proceed. SWEET- the first thing I will do is pull it apart and have a look at the pinion bearing, sounds like it will be obvious if it's damaged and failing. And, if it has trashed anything else inside- bigbadswingdaddy- now I know my options as far as what to replace it with. My Suburban has the 270 six with the 3 speed behind it. It cruises at a very reasonable rpm going down the road at 55-60 so I assume it's the 3:08 trans. I will get out there and do the spin test to determine what it is. I wouldn't want to jump up to a 3:90 if it is the 3:08. Thanks again to both of you.
