Switching to synthetic: Noise reduction?

[Jkalplus1]

Gents,

I took the car in for a 1000km post overhaul service: retorque the head, adjust valves, set dwell and timing.

My question:  following this break-in service job, I replaced the manual gearbox oil with synthetic ATF, and the engine oil with 10W40 synthetic oil with proper levels of ZPPD.  Am I delusional or are my engine and drivetrain less noisy?  I have had that same "perception" with other cars too when switching from dino to synthetic, and I am wondering if it is for real or if I am imagining things?

[waqas]

You're not imagining things: the noise reduction is real. However, the oil type has no contribution to this effect. The other service items make all the difference, particularly the valve adjustment.