T5 issues

[dans_vz]

Hi guys, wondering if anyone knows how to solve a problem of a T5 gearbox being a bit noisy in 1st 2nd and 3rd at times? I have castrol gearbox fluid 80w-90 in it. And also I cant get 3rd when gearing down except if I just enter 2nd then I can go into 3rd. Any ideas why? Cheers.

[GTP 85]

Fresh Dextron 3 fluid, and a bottle of penrite lubrizol fixed a similar problem with mine

[Uber_Matt]

Id say it might be the wrong fluid, I recently asked what fluid is best for T5 and everyone was saying that you MUST use dexron 3 ATF with the lubrizol additive as per holden manual, T5s dont like gear oil.

Even in the sates they use Dexron 3 in their T5s.

[immortality]

yep, dump the oil and run dexron III. might pay to change the fluid twice because after the first change there is still going to be some of the old oil in the gears/synchros. the 80w90 gear oil is a lot thicker/heavier then the dexron III, this seems to create extra drag between gears and shaft. when you try to change gears the synchros are having trouble overcoming that extra drag to equalise the gear speed to shaft speed causing your shifting troubles. this problem gets worse as the synchros wear with time.

[GTP 85]

oh, and another thing! low oil makes for a noisey gearbox too! lol. worked out that mine was over half a litre too low!! so make sure you refill on a flat surface