I thought I would share the solution to my problem since I have read other threads with similar issues. I just bought this 2005 AWD Astro Cargo Van for my business. I live in Iowa so the AWD is great! It has 170,000 miles on it, but they are highway miles from the previous leasee. From the start I noticed a kind of slight "grabby" feeling as I would accelerate from a stop on dry pavement going in a straight line. After reading threads about the Auto TrakII synthetic lube, I had the transfer case fluid changed. The mechanic said I already had the Auto trakII in the transfer case, but it was old and broken down. That fixed the problem with the "grabby" issue immediately! My main issue however has been that the "service awd" light would come on and off, and when the light was on, I had no awd. It would happen like this. When I go to start the van, most of the time I would hear a clicking noise in the kick panel by my left foot. About 4-5 clicks. Then the light comes on and stays on. Then, I get to my next job site, turn the van off, start it back up an hour later and no clicking sound or "awd light". More than half the time the light comes on though. I figured it could be the encoder motor, but didn't want to spend $581.00 on a hunch, "dealer price". So I found out I could get a non-OEM encoder motor at Oreilly's for 145.00 + 25.00 core, lifetime warranty. I just installed it today and it works PERFECT! I know this because we just got 6 inches of snow. I am curious to see how long this encoder motor lasts though. Thanks Astrosafari.com!