| 2023-08-11 | One of eight in a B-52 |
| 2023-02-21 | Something that can roar or purr |
| 2022-06-10 | Road runner? |
| 2022-04-12 | Driving force? |
| 2021-02-28 | Its size may be measured in liters |
| 2017-02-12 | It must turn over to start |
| 2014-05-13 | V-8, e.g. |
| 2014-04-18 | It's often described by horses |
| 2013-07-07 | It may purr or roar |
| 2013-05-28 | V-8, e.g. |
| 2012-03-02 | Thing worked on in a garage |
| 2010-11-25 | It goes in front of a coal tender |
| 2010-10-21 | Metal casting housing automotive cylinders |
| 2009-09-20 | You might give this a gun |
| 2009-08-30 | It typically has lots of horses |
| 2009-07-18 | It turns over before it runs |
| 2009-02-15 | Caboose's opposite |
| 2008-11-09 | Power source |
| 2008-08-03 | Train head |
| 2008-01-30 | Driver |
| 2007-08-08 | Object of a tuneup |
| 2007-07-28 | Purrer |
| 2005-05-29 | It might be found in a stall |
| 2004-01-25 | Dragster's pride |
| 2001-01-05 | Gas guzzler |
| 1998-02-26 | Pistons' place |
| 1997-04-30 | Head of a train |
| 1996-09-22 | Powering force |
| 1995-01-19 | Battering ram or catapult |