2009 Cadillac STS Cooling System Parts

This table covers the engine coolants and antifreeze formulations specified for this cooling system. Typical signs include a rising temperature gauge, rusty or sludged coolant, or a heater that blows cold. Use the chemistry named in the notes. Mixing silicate, OAT and HOAT formulas can gel in the radiator. Read more

16 Coolant / Antifreeze parts for the 2009 Cadillac STS come from 6 brands — PRESTONE, PEAK, VALVOLINE and 3 other brands. The "Popular" part is FVP MV5050GAL. Every part fits all 3 engine options (3.6L V6, 4.4L V8 Supercharged and 4.6L V8).

In the Compatible With All Colors grade, PRESTONE supplies 1 part: grouped under the catalog's "Compatible With All Colors" designation — the notes column spells out what sets them apart. A representative part number is PRESTONE AF3055.

The Economy section lists 4 options from FVP, PEAK, PRESTONE and 1 other brand — the catalog's value-priced group. FVP MV5050GAL is listed in this group.

In the Premium grade, PRESTONE and PEAK supply 4 parts: a step above OE specification in materials, tolerances or warranty terms. A representative part number is PRESTONE AF2100.

In the Standard Replacement grade, VALVOLINE, PRESTONE, ACDELCO and 2 other brands supply 7 parts: built to original-equipment specification. A representative part number is ACDELCO 105027.

This table covers the Coolant Bleed Hose fittings. Read more

This group shows a single part: GM GENUINE 12589732.

This table covers the hard pipes and extra hoses in the coolant circuit. Read more

7 Coolant Hose / Pipe parts for the 2009 Cadillac STS come from 5 brands — GATES, GM GENUINE, CONTINENTAL and 2 other brands. The "Popular" part is CONTINENTAL 61267. 1 part fits every engine; the other 6 are engine-specific.

Part numbers include CONTINENTAL 61267, GATES 23133 and ACDELCO 20149S, among others listed above.

This table covers the seals at the Coolant Hose / Pipe. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

2 Coolant Hose / Pipe Seal parts are listed for the 2009 Cadillac STS, from ELRING and GM GENUINE. 1 part fits every engine; the other 1 is engine-specific.

Listed part numbers: ELRING 943630 and GM GENUINE 12623519.

This table covers the seals at the Coolant Hose Connector / Flange. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

One part is listed for the 2009 Cadillac STS — ELRING 943020.

This table covers the gaskets that seal the Coolant Pipe. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

One part is listed for the 2009 Cadillac STS — AJUSA 01154600.

This table covers the overflow / expansion tanks that hold extra coolant. Read more

2 Coolant Reservoir parts are listed for the 2009 Cadillac STS, from DORMAN and SKP. All of them fit every engine offered in the 2009 STS.

Listed part numbers: DORMAN 603141 and SKP SK603141.

This table covers the caps on the overflow / expansion tank. Typical signs include a leak at the neck, a cap that will not hold pressure, or a missing tether. Match the pressure rating or thread in the notes — radiator, reservoir and fuel caps are not interchangeable. Read more

4 Coolant Reservoir Cap parts are listed for the 2009 Cadillac STS, from MOTORAD, AUTOTECNICA and GM GENUINE. 3 parts fit every engine; the other 1 is engine-specific.

This group includes AUTOTECNICA GM0613026, GM GENUINE 15076936 and MOTORAD T46 and the remaining parts above.

This table covers the seals at the Coolant Reservoir. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

This group shows a single part: GM GENUINE 12623461.

This table covers the Cooling Fan control modules. Read more

US MOTOR WORKS supplies the 3 Cooling Fan Control Module parts for the 2009 Cadillac STS.

Listed part numbers: US MOTOR WORKS 16749, US MOTOR WORKS 16789 and US MOTOR WORKS 16795.

This table covers the adapters used to pressure-test this cooling system. Read more

4 Cooling System Tester Adapter parts for the 2009 Cadillac STS come from 2 brands — GATES and MOTORAD. Every part fits all 3 engine options (3.6L V6, 4.4L V8 Supercharged and 4.6L V8).

This group includes GATES 31431, GATES 31391 and MOTORAD 3128 and the remaining parts above.

This table covers the Hose clamps. Read more

This group shows a single part: GM GENUINE 11518519.

This table covers the intercoolers that cool turbo or supercharger charge air. Read more

This group shows a single part: GM GENUINE 12589732.

This table covers the radiators that dump engine heat to airflow through the core. Typical signs include overheating in traffic, a wet core, or coolant that disappears with no puddle. Replace the cap if it cannot hold the rated pressure, and bleed the system after the swap. Read more

25 Radiator parts for the 2009 Cadillac STS come from 11 brands — OSC, GPD, AGILITY and 8 other brands. The "Popular" part is FAMOUS BRAND 438175. 2 parts fit every engine; the other 23 are engine-specific.

The Economy section: 9 options from GPD, FAMOUS BRAND, ULTRA-POWER and 1 other brand. FAMOUS BRAND 438175 is listed in this group.

Standard Replacement: 16 parts, from OSC, AGILITY, DENSO and 4 other brands. A representative part number is DENSO 2219240.

This table covers the caps that hold system pressure at the radiator or reservoir neck. Typical signs include a leak at the neck, a cap that will not hold pressure, or a missing tether. Match the pressure rating or thread in the notes — radiator, reservoir and fuel caps are not interchangeable. Read more

2 Radiator Cap parts for the 2009 Cadillac STS come from 2 brands — ACDELCO and GATES. Every part fits all 3 engine options (3.6L V6, 4.4L V8 Supercharged and 4.6L V8).

Part numbers include ACDELCO RC116 and GATES 31532.

This table covers the fan assemblies (and clutches, where listed) that pull air through the radiator. Read more

12 Radiator Fan Assembly parts are listed for the 2009 Cadillac STS, from VDO / CONTINENTAL, DORMAN, FOUR SEASONS and 5 other brands. DORMAN 620958 carries the "Popular" badge. 2 parts fit every engine; the other 10 are engine-specific.

Economy: 4 parts, from DORMAN, SKP and GPD. A representative part number is DORMAN 620958.

The Standard Replacement section: 8 options from VDO / CONTINENTAL, FOUR SEASONS, AGILITY and 2 other brands. AGILITY 6010030 is listed in this group.

This table covers the Radiator Fan blades. Typical signs include chatter, streaks, or a skip at the top of the stroke. Confirm left and right lengths in the notes — they are often different. Read more

GM GENUINE supplies both parts for the 2009 Cadillac STS.

This group includes GM GENUINE 19435353 and GM GENUINE 19129773.

This table covers the Radiator Fan clutches. Typical signs include slip at highway speed, chatter on takeoff, or a pedal that stays low. Resurface or replace the flywheel with the clutch — a heat-checked flywheel wastes the new disc. Read more

7 Radiator Fan Clutch parts for the 2009 Cadillac STS come from 6 brands — FVP, HAYDEN, US MOTOR WORKS and 3 other brands. The "Popular" part is HAYDEN 2982. 2 parts fit every engine; the other 5 are engine-specific.

This group includes HAYDEN 2982, US MOTOR WORKS 22632 and FOUR SEASONS 46132 and the remaining parts above.

This table covers the Radiator Fan motors. Typical signs include no motion, a squeal, or a motor that only runs on one speed. Confirm power, ground and the control module before replacing the motor. Read more

This group shows a single part: GM GENUINE 1581137.

This table covers the Radiator Fan resistors. Read more

3 Radiator Fan Resistor parts for the 2009 Cadillac STS come from 3 brands — AUTOTECNICA, GM GENUINE and STANDARD MOTOR PRODUCTS. 1 part fits every engine; the other 2 are engine-specific.

This group includes AUTOTECNICA GM1320083, GM GENUINE 25881844 and STANDARD MOTOR PRODUCTS RY2010.

This table covers the upper, lower and connecting hoses between radiator, engine and reservoir. Typical signs include swelling, cracks, a soft spot, or a leak at a clamp. Replace adjacent aged hoses while the system is drained — they share the same heat cycle. Read more

22 Radiator Hose parts are listed for the 2009 Cadillac STS, from GATES, ACDELCO, DAYCO and 1 other brand. DAYCO 72650 carries the "Popular" badge.

This table covers the senders that report coolant temperature to the gauge or ECU. Typical signs include a gauge that sits on empty or overheat, or a lamp that does not match what the engine is doing. Rule out the cluster and the wiring before replacing the sender. Read more

39 Temperature Sender / Sensor parts for the 2009 Cadillac STS come from 18 brands — STANDARD MOTOR PRODUCTS, NTK, WALKER PRODUCTS and 15 other brands. The "Popular" part is NTK EF0008. Grades run from Economy through Standard Replacement; Standard Replacement is the most populated section, led by STANDARD MOTOR PRODUCTS, WELLS, NTK and 9 other brands.

This table covers the thermostats that open the coolant circuit at the specified temperature. Typical signs include slow warm-up, a gauge that climbs in traffic, or heat that never quite arrives. Replace the housing gasket with the thermostat and bleed the system so a trapped air pocket does not cook the new part. Read more

13 Thermostat parts are listed for the 2009 Cadillac STS, from MOTORAD, GATES, AISIN and 4 other brands. GATES 33808 carries the "Popular" badge.

The Heavy Duty section lists 1 option from MOTORAD — rated for severe service. MOTORAD 5339180 is listed in this group.

The Premium section: 1 option from MOTORAD. MOTORAD 7339180 is listed in this group.

The Standard Replacement section: 5 options from GATES, MOTORAD, AISIN and 2 other brands. GATES 33808 is listed in this group.

6 ungrouped parts are not assigned to a grade, with the same engine-level match.

This table covers the seals at the thermostat housing and water outlet. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

37 Thermostat / Thermostat Housing / Water Outlet Seal parts for the 2009 Cadillac STS come from 9 brands — FEL-PRO, GM GENUINE, MAHLE / CLEVITE and 6 other brands. The "Popular" part is FEL-PRO 35858. A list this long means Thermostat / Thermostat Housing / Water Outlet Seal applications vary by configuration — the notes carry the qualifiers.

This table covers the housings and outlets the thermostat sits in. Read more

One part is listed for the 2009 Cadillac STS — ACDELCO 12706566.

This table covers the pumps that circulate coolant through the block and radiator. Typical signs include coolant at the weep hole, pulley play, or a growl from the front of the engine. Replace the thermostat and refill with the specified coolant whenever the pump comes off. Read more

28 Water Pump parts are listed for the 2009 Cadillac STS, from FVP, GATES, GM GENUINE and 13 other brands. BECK/ARNLEY 1312378 carries the "Popular" badge. Grades run from Economy through Standard Replacement; Standard Replacement is the most populated section, led by GATES, GM GENUINE, GMB and 5 other brands.