Looking at possibly buying a 2013 G37S 6MT with 142K. I've read that the gallery gasket issue was mostly resolved by the time the 2013's hit the market. Has this been confirmed?

I am also aware of the heater core hose failures and the Clutch Concentric Slave Cylinder (CSC). Is there anything else that I should be aware of?

 

The gasket issue was resolved in the 2012 model year. It seems to manifest at high mileage, like 100k+.

The coolant hose connector issue is an easy fix, also typically occurring after high mileage. I've still not replaced mine, but there's only 52k miles on the car.

The CSC issue... I don't know if the design flaw was ever fixed. Mine went out under warranty at 18k miles, and it was repaired with an OEM replacement. It's been fine ever since, but I still worry about it. RJM claims his clutch pedal reduces the underlying cause of the CSC failure. IDK about that, but you're going to want the pedal anyway.

Those are the big 3 known issues, and clearly I'm still gambling with them. You've been doing your research... good for you.

 

Just read a post on reddit this week that a 2015 Q40 sedan had gallery gasket issues at 68k miles I think? The seals were upgraded to a metal composite compared to the original paper one, though they are still experiencing the hardware backing out. This is why most kits also include the allen head hardware. Other than the heater core hose and CSC, most other problem item has been the sunroof drains backing up.

Here is the thread from reddit: https://www.reddit.com/r/G37/s/FB4EC7nFVV