PJJackson

I don't believe it is the diff because the sound seems to come from the footwells and not from behind the rear bulkhead, but it's possible the sound is traveling through the tunnel and tricking my ears. Thank you for sharing your experience with these Tracsport gearkits. That does make me wonder if I have a bad bearing in the box. I think I will need to drive the car more and listen more closely to the location of the noise and whether the noise is there on acelleration (and just less noticalbe because it is covered by engine load and induction noise). I just learned that the semi helical gearkit is only on 1st through 4th so it would interesting to see if the noise is there in 5th gear. Ugh! I was hoping to work on this during the winter, but I may need to drive it this summer to diagnose it and fix it next winter, if there really is a problem.

That's interesting. I will consider that.

This year I bought a left hand drive Birkin with 5k miles on it built in 2013. It has a 2.0L Duratec, a 5-speed Type 9, and a Subaru diff. The gearbox was rebuilt by Tracsport with the semi helical gearkit. I'm surprised by how much noise this transmission makes under engine braking, but not noisy at all when accelerating. I can hear plenty of exhaust note when accelerating, but barely any when I lift my foot off the gas pedal. I've never owned a car like this before, so I'm not sure what to expect. It's surprising to me that it would be a bad bearing since the transmission only has 5k miles on it (of course it has obviously sat for long periods of time and maybe that would allow some corrosion to occur in the bearings). These transimission are supposed to be "95% quieter" than straight cut gears, but I would expect louder than stock gears. Has anyone had this experience with this transmission and gearkit?

Thanks! I did you see that one. I'm in PA, but I'm willing to travel. If I go to CA I might as well go to the US Dealer for GBS.

I have been looking at kits and would like to see a finished GBS Zero without traveling to the UK. Does anyone have one that they wouldn't mind showing off?