GCG Turbos in Sydney did a great job refurbing my Garrett GT25R. Essentially worn ball bearings in the centre cartridge. Asked them to fit a new 10psi wastegate (then boost adjustable to higher as req'd). Every refurb aspect was treated like an instrument I'm glads to say. Even though the turbo has the smaller T25 flange compared to a T3, its fitted with the biggest compressor and exh housings and suits my needs of a rapid boost turbo, so no lag between corners. (242GT T. RHD)
Couple of pics before refittment. Exhaust first section is 3" custom shaped with thermocouple temp sensor on top & best wideband O2 sensor further down. Its custom made to clear everything by Roadway Exhaust in Canberra.
Reader info - Volvo used Garrett turbos for about 4 years before moving to Mitsubishi. In general Garrett for higher rpm performance, and Mitsub for superior low rpm performance (best for auto trans).
Anthony