I have 2nd gear slippage on my, recently bought, 240Z. 1st and third gears seem not to slip. Please tell me if there is an adjustment to correct this. I recently installed an oil cooler; could this have caused the slippage?

The oil level seems OK, but I'm still confused on how to check it. I was told that to check the AT oil level I should run the car; then turn it off, wait 15 min; then check the AT level with the car engine Off -- is this correct?

Thank you

Well, you obviously have an automatic transmission. On most all AT's you check the fluid level while the engine is running with all componets are at operating temp. Fluid should be between the two factory marks and the fluid should not smell or look burnt.

Now, regarding slippage in second gear.......second gear is most always the gear that gets the most abuse in a transmission, wether AT or manual. So your trans just may be getting worn, indicated by second gear no longer grabbing as well as the other gears. I'm not familiar with the Z car AT, so I can't tell you if it is possible to adjust your second gear band. I'm almost sure someone with more knowledge on this subject will jump in and help out here. Hope this info helps explain things a little!