2006 Won't stay in 4th
 

Hi,
It's good too know there is a group out here. My wife bought a 2006 Mini S with a 6 speed manual. There is 60000 on the clock. I was told and then shown that it will not stay in/go into 4 gear. It pops right back out with a grinding. If I was guessing, I would think that the syncro is gone. We stopped driving it, I will drop the transmission oil this weekend for a look see. We haven't had the car only a couple of months, and when we first got it, I didn't notice any odd feelings when shifting. There isn't any throw adjustment on these things is there? Hoping someone could point me in a direction. I am a fair mechanic. Just not familiar with these. I have rebuilt several older style trannys (Fiat and Ford) in my span. I had also heard there isn't any parts available for there, Hope that't not so. Thanks much for any insight.
Randy S.