Clutch disengage issue

[Navman123]

I have a 2005 3.0L ST-R. When I bought it it was difficult to change gears, especially into 1st from stationary or moving. Took to mechanic for full service, new gearbox oil and clutch fluid/bleed, and lengthened master cylinder pushrods since it was engaging 1 off the floor. Fine for 2 weeks then started acting up again. Smooth gear changes when cold, but when at operating temp extremely hard to shift gears, notchy and requiring a lot of force. So I lengthened the push rod a little more keeping in mind I need free play at the top, and solved all my issues. Smooth gears hot and cold...but another two weeks down the track, it shifts now shifts smoothly when HOT and is a bitch when it's COLD( especially at 530am winter when I start it up). It's gotta be a temperature or fluid issue? Or could it be something to do with the selector or clutch plate? I'm told its a relatively new aftermarket clutch so this shouldn't be the case. Any ideas?

 

[Stelianos]

any idea what was the viscocity of the gearbox oil? should be SAE 75W-85

 

[Navman123]

I will check the oil viscosity tomorrow. Symptoms point to a oil/temp issue, but i don't understand how things can reverse like they have (ie good shifting when cold crap on hot, but now crap on cold good on hot).