Owner complaints, recalls, fuel economy and safety ratings from public NHTSA and EPA data, updated Oct 17, 2026.
Fuel economy
17–19 mpgcombined; city 14–16, highway 21–25; every version of this model year
Five years of fuel
$17,100–$23,670U.S. average; Ohio $15,280–$22,310 at local prices; every version of this model year; fuel only, not other costs of owning it; 15,000 miles a year, at EIA fuel prices for the week of Oct 12, 2026
NHTSA overall safety rating
Not ratedNHTSA has no overall rating for this year
NHTSA's VIN data lists these trims for the 2006 STS. A trim's engine and numbers are shown as its own only where EPA names versions after the trim and no other version could be it; "seen with" means a source shows that engine on the trim, not that it was the only one. Recalls and complaints cover the whole model year: whether a recall applies to a car depends on its VIN, on NHTSA's recall lookup.
Owners have filed 139 complaints with NHTSA about the 2006 STS. These are unverified owner reports, counted by the part of the car they name; one complaint can name several parts. Counts aren't adjusted for how many were sold, so they don't show how reliable a car is.
Complaints by part of the car
Part
Complaints
Crashes
Fires
Injuries
Air bags
57
12
2
17
Electrical system
21
1
3
2
Engine
20
3
2
6
Fuel/propulsion system
18
0
3
0
Power train
13
1
0
1
Electronic stability control (ESC)
8
1
1
1
Engine and engine cooling
8
1
1
1
Seats
6
0
1
0
Unknown or other
6
0
0
0
Vehicle speed control
6
1
0
0
Steering
5
1
0
1
Seat belts
4
3
0
4
12 more parts
Fuel system, gasoline
3
0
0
0
Latches/locks/linkages
3
0
0
0
Service brakes
3
0
1
0
Suspension
3
0
0
0
Equipment
2
1
0
1
Tires
2
1
0
0
Equipment adaptive/mobility
1
0
0
1
Service brakes, electric
1
0
0
0
Service brakes, hydraulic
1
0
0
0
Structure
1
0
0
0
Traction control system
1
0
0
0
Wheels
1
0
0
0
Complaints by model year
Newer years have had less time to collect complaints, and counts aren't adjusted for sales, so a shorter bar doesn't mean a more reliable year.
NHTSA lists 4 recall campaigns for the 2006 STS over its history. Campaigns are matched by model and year, so each one may apply to a given car, and its repair may already be done: check a VIN on NHTSA's recall lookup for the open recalls on that exact car.
General Motors LLC (GM) is recalling certain model year 2004-2007 Cadillac CTS-V vehicles manufactured October 6, 2003, to March 15, 2007, and 2006-2007 Cadillac STS-V vehicles manufactured June 23, 2005, to March 15, 2007. In the affected vehicles, the electrical terminals of the fuel pump module may overheat resulting in the melting of the flange material.
Risk: If the flange melts, a hole may be created allowing the fuel pump to leak fuel, causing the vehicle to stall, increasing the risk of a vehicle crash. Additionally, leaking fuel in the presence of an ignition source increases the risk of a fire.
Remedy: GM will notify owners, and dealers will replace the fuel module and fuel tank jumper harness, free of charge. GM sent out interim notices in late October. The recall began on March 12, 2015. Owners may contact Cadillac customer service at 1-800-458-8006. GM's number for this recall is 14405.
ON CERTAIN PASSENGER VEHICLES, THE REAR AXLE PINION SEAL DOES NOT MEET ALL OF THE SPECIFICATIONS AND MAY EXPERIENCE A FLUID LEAK.
Risk: A REAR DIFFERENTIAL FAILURE MAY CAUSE LOSS OF MOTIVE POWER AND POSSIBLY LOSS OF CONTROL INCREASING THE RISK OF A CRASH.
Remedy: DEALERS WILL REPLACE THE PINION SEAL FREE OF CHARGE. THE RECALL BEGAN ON FEBRUARY 1, 2008. OWNERS MAY CONTACT CADILLAC AT 1-800-458-8006 OR HTTP://WWW.CADILLAC.COM; PONTIAC AT 1-800-620-7668 OR HTTP://WWW.PONTIAC.COM; AND SATURN AT 1-800-972-8876 OR HTTP://WWW.SATURN.COM.
CERTAIN VEHICLES EQUIPPED WITH V6 ENGINES MAY HAVE A CONDITION WHERE FUEL IS NO LONGER SUPPLIED TO THE ENGINE. THIS CONDITION OCCURS WITHOUT THE ILLUMINATION OF THE FUEL LEVEL LOW INDICATOR LIGHT OR THE WARNING CHIME.
Risk: IF THE ENGINE STOPS RUNNING, THE OPERATOR WILL NOT BE ABLE TO RESTART THE VEHICLE WHICH COULD INCREASE THE RISK OF A CRASH.
Remedy: DEALERS WILL REPROGRAM THE ELECTRONIC CONTROL MODULE (ECM) WITH NEW SOFTWARE FREE OF CHARGE. OWNERS WERE NOTIFIED IN DECEMBER 2005 AND ASKED TO MAINTAIN AT LEAST 1/4 OF A TANK FUEL LEVEL TO AVOID THIS CONDITION UNTIL THE PARTS ARE AVAILABLE. THE PARTS ARE NOW AVAILABLE, OWNER RENOTIFICATION BEGAN ON MARCH 23, 2006. OWNERS MAY CONTACT CADILLAC AT 1-866-982-2339.
ON CERTAIN PASSENGER VEHICLES EQUIPPED WITH ALL WHEEL DRIVE AND A 3.6L V6 ENGINE, THE TORQUE MONITORING FUNCTIONS OF THE ELECTRONIC THROTTLE CONTROL (ETC) ARE NOT ENABLED. THESE FUNCTIONS CAN LIMIT ENGINE SPEED AND TORQUE IF UNUSUAL ENGINE CONTROL MODULE (ECM) HARDWARE OR SOFTWARE FAILURES OCCUR.
Risk: WITHOUT THESE FUNCTIONS ENABLED, A PERSISTENT ECM FAILURE COULD RESULT IN A THROTTLE OPENING GREATER THAN COMMANDED BY THE DRIVER AND A CRASH COULD OCCUR.
Remedy: DEALERS WILL REPROGRAM THE ECM ON THESE VEHICLES FREE OF CHARGE. THE RECALL BEGAN ON JANUARY 24, 2006. OWNERS MAY CONTACT CADILLAC AT 1-866-982-2339.
Carmakers sent NHTSA 752 service bulletins and notices that cover the 2006 STS, the latest on Jul 18, 2025. They tell dealers how to fix known issues.
The parts they mention most: equipment (347), electrical system (159), engine and engine cooling (80), power train (66), equipment adaptive/mobility (57).
NHTSA defect investigations
Opening an investigation isn't a finding of a defect. Outcomes are as NHTSA's summary states them. A recall is shown as an investigation's outcome only where NHTSA's summary names it; other recalls NHTSA's file lists with it are marked as listed, not caused.
Investigation
Part
Opened
Status
Preliminary evaluation PE07037 FAILURE OF THE REAR DIFFERENTIAL · covers 3 makes
The owner's manual gives the oil and how often to change it. We show oil facts only once we've checked them against the manual, and we haven't yet for the 2006 STS.
NHTSA manufacturer communications, file of Oct 17, 2026
NHTSA defect investigations, file of Oct 17, 2026
NHTSA 5-Star Safety Ratings, file of Aug 7, 2026
U.S. Energy Information Administration, file of Oct 12, 2026
Fuel cost: EPA mpg with fuel prices for the week of Oct 12, 2026 and electricity prices for Jul 2026. Source: U.S. Energy Information Administration (Oct 2026). Complaints are unverified reports owners filed with NHTSA. About the data