Golf IV / Jetta IV :: 3rd Gear Will Grind When Driving For More Than Half An Hour / Over 2800 RPMs

I noticed through careful investigation that my 03 GTI 1.8T (180,000 KM's or 111,850 miles) will grind 3rd when in these conditions:

1. When the car has been driving for more then half an hour and everything is hot

2. When the car is over 2800 RPM's while hot (ie. getting on a highway)

Now I know lot's of people blame syncro's and yes I could see that my car has had 8 previous owners so I can't say they all shifted perfect. But what I do know is that when I downshift from either 4th or Neutral it will never grind even when I don't Rev Match or "Blip" the throttle. So it can't be syncro's in my opinion.

So what I've done to the car to rule out some problems were:

- Change the gear oil from what ever it was before to Royal Purple 75W-90 (NO luck.)

- Then I added a short shifter and adjusted my cables properly (still No luck)

- Finally I noticed my shifter was sloppy and one of my bushings were torn so I bought 42 DD's metal bushings and the shifter did stiffen up a lot, however!!! (No luck)

I know it's not my driving technique because I watch my foot depress the clutch fully and then I gently push it into third. I also know I'm shifting correctly because I can double clutch and normally shift through every other gear properly without any grinds or clunks. Just the devilish 3rd gear.

I would like to hear the solution. I'm going to change the oil one more time to Redline MT-90 and see how that goes, but if that doesn't work I might just tear apart or get a new tranny.