I've had 2 oil changes done by my dealer w/ Castrol Syntec... The 1st time my Z took 5 qts. The 2nd time they only used 4. The owner's manual lists the engine capacity as 5 qts... Is there any reason why it might take less, or did the service guy do it wrong? I can always add the 5th qt myself.

 

On my second oil change, all I put in was 4 qts, and it was enough... so I think it should be fine.

 

Should take 5 qts. if the filter was changed. Check the dip stick...make sure the level is right.

 

I talked to the tech... He said the oil level was OK on the dipstick. I'm going to check it myself, but assuming he's right, should I even bother adding a 5th qt?

 

It's a hard stick to read. Could be he read it wrong. Check it yourself and ONLY add oil if it's low. If you overfill it will cause problems.

 

It took my engine a long time to drain (over 10 minutes) and it only took 4.5 quarts to get to the middle of the zone on the dipstick. It was hot and I did change the filter. If you don't wait for it to drain fully or don't change the filter it will take less to fill it up.

 

also make sure to check the oil when the engine is NOT running to get a more accurate answer