I drove my son to the bus stop this morning noticing I was almost to 86K miles and when I drove back home the odometer flipped, the engine made a funny grinding purr and there was a burning odor.

Geex, I wish I could see the car. Please describe the odor as well as you can: engine exhaust, electrical fire, a brake-like odor, anything you can add, And what do you mean odometer 'flipped"? Went back to O? They don't do that. and do you mean you were almost to 86K total miles, or 86 miles on your trip this morning? A funny grinding purr. Beginning to sound like a radiator hose burst. Ok, did you continue home, and if so how far and did it make it ok, overheat, anything? Any warning lights on dash appear? I know, lots of questions but trust me, I'm on your side trying to help---- from behind a keyboard.

No too sure on type of odor but it smelt of burning rubber, definitely not electrical. When I mention flipped-meaning it went from 85.9K to 86K total mikes. No, there wasn't any dash board warning signals and I was about 50 feet from my garage. Just got back from driving other kids to school and there was nothing that seemed to be wrong with the car. No odor but an occasional noise of soft grinding. Just got new tires and switched it into 4wd last week. Maybe I'll take it to them to see if the wheels are okay. Would hate it to be the differential.

Since you have made another trip since this happened, it might have just been a "fluke". I would keep an eye on it and let us know if it happens again. Since you didn't say anything about "engine light on", I can only presume it is nothing to do with the engine. Try in and out of 4x4 and see if that makes any difference. Spedo turnover may have just been going from 86999 to 87000. Digital odometers are pretty accurate about counting.