The 2004 Buick Regal runs on regular unleaded.
The 2001 Buick Regal has a 4-speed automatic.
The 2002 Buick Regal has a 4-speed automatic.
The 2014 Buick Regal has a 6-speed automatic.
The 2003 Buick Regal has a 4-speed automatic.
The 2011 Buick Regal has a 6-speed shiftable automatic.
The 2013 Buick Regal has a 6-speed shiftable automatic.
The 2012 Buick Regal has a 6-speed shiftable automatic.
Depends on the engine
dextron II (2)
The 2013 Buick Regal runs on regular unleaded.
The 2001 Buick Regal runs on regular unleaded.