I thought I'd better write this up for people who own any LS1 powered vehicle with the 6 speed Tremec bolted to it. I had trouble with shifting the gears in my VY Commodore so I decided to dump all the fluid out of the gearbox, when it came out, it was all black so I'm glad I did that as Holden don't specify any fluid change intervals for this transmission,as I said in other posts, I don't think they expect anybody to still have the car after 200,000 kms, mines nudging on 263,000 kms, I'd say the service schedule only covers the warranty period. Yeah , they use Dexron III fluid just like the T5's do and I've decided to change it every 100,000 kms, the gearbox shift feels a lot better now.

I think I posted it somewhere here as well, but Penrite and Mainlube do a gear oil that is suitable for the T56 is the commodores. You think its good now.. it is better again.