Moving beyond the orginal question. Nissan Synchros in the Z are not all that great for what ever reason, many people have issues with it, a few so bad that they had them replaced under warranty. Personally 4th to 5th is the worst for me. I have to shift slowly to avoid grinding. Odd thing is it never gives me any issue when I am at the track shifting at near red line
.I have changed the gear fluid in the MT to a 50/50 mix of Redline MTL and MT-90, which is now MT-85. I did this to have the transmission shifting feel smoother, it had no effect on the synchros.
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GTR TT 493Whp/431lbft, Ecutek, Southbend 6puck,Quaife, RPM RollBar 4Point, R888R, JRZ RSPro F(10R/10C) R(10R/6C) 1000f500r inlbs+150inlbs Tender, SPL everywhere.
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