i have a 147 2.0 ts selespeed,65,00 miles. and had a crunch changing from second to third,still drove ok.i decided to tackle the problem and remove the gearbox to replace third syncromesh???(after weeks of constantly studying the forums on the web).i had no previous mechanical experiance but thought if i take a digital photo of every stage with written notes and use basic common sense how hard can it be.
well!! every thing went ok,a few bolts were a pain to get to, but the sun was shining,the misses made plenty of tea, and i was covered from head to toe in grease.
After splitting the gearbox i found that with no doubt i definitly had badly worn teeth on third syncro.second allso looks dodgy so i will allso change this.
I thought i would post this as a lot of people seem to have similar problems and it may help them deciding whether to tackle the problem or not,(and keep that £500 in there pocket rather than the dealers.
In the following photo you can clearly see the difference between the worn teeth on second and third syncro, and the good ones.The syncro teeth are the small silver pointed ones right above or below the brass rings with teeth.
see the photo here