tirewheelguide

2009 Cadillac STS tire and wheel sizes, bolt pattern and tire pressure

Bolt patterns 5x115 (Europe, USA) or 6x115 (USA), depending on the market version.

Tires for the 2009 Cadillac STS

Sizes most trims come with first. Open your trim below for its exact size.

  1. 235/50R17 front + 255/45R17 rear Best-rated standard on 2 trims · USA, Europe
    Check price on Amazon · 235/50R17 front Check price on Amazon · 255/45R17 rear
  2. 235/50R17 Best-rated standard on 1 trim · optional on 2 · Europe, USA
    Check price on Amazon · 235/50R17
  3. 255/45R18 front + 275/40R19 rear Best-rated standard on 1 trim · USA
    Check price on Amazon · 255/45R18 front Check price on Amazon · 275/40R19 rear

Also listed: 235/50R18 + 255/45R18 235/50R18 255/45R18 235/40R19 235/40R19 + 265/35R19 245/40R19 245/40R19 + 275/35R19 255/40R19 + 275/40R19 255/40R19 + 285/35R20

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Trims sold in 2009
4
Generation
GM Sigma ll sold in 2 market versions

4 trims sold in 2009

Sold in 2 market versions with different tire sizes and bolt patterns. Open a trim for its tire and rim sizes, bolt pattern and tire pressure.

Cadillac STS GM Sigma ll

2008–2012 4 trims

Europe

2 trims
STS 3.6i 253 hp · 3.6L LY7 V6 235/50R17 95V / 255/45R17 95V 4 fitments
Generation
GM Sigma ll · 2008–2012
Market
Europe
Power
253 hp
Engine
3.6L LY7 V6, Petrol
Center bore
70.3 mm
Bolt pattern
5x115
Thread
M12 x 1.5
Check price on Amazon · 235/50R17 Check price on Amazon · 255/45R17 Wheels 17x7.5 ET51 · 5x115 · 70.3 mm on Amazon
Tire sizeRim size and bolt patternPressure, psi
Front235/50R17 95VRim 17x7.5 ET51 5x11530 psi
Rear255/45R17 95VRim 17x8 ET51 5x11530 psi
Front235/50R18 97WRim 18x8 ET51 5x11530 psi
Rear255/45R18 97WRim 18x8 ET51 5x11530 psi
Front235/40R19 95WRim 19x8 ET50 5x11530 psi
Rear265/35R19 95WRim 19x8.5 ET50 5x11530 psi
235/50R17 95SRim 17x7.5 ET51 5x11530 psi

How to read 95V: 95 is the load index (up to 1,521 lb / 690 kg per tire) and V the speed rating (up to 149 mph / 240 km/h). ET51 is the wheel offset: how far the mounting face sits from the rim centre, in millimetres. Compare offsets in the wheel offset calculator.

STS 4.6i 321 hp · 4.6L LH2 V8 235/50R17 95V 4 fitments
Generation
GM Sigma ll · 2008–2012
Market
Europe
Power
321 hp
Engine
4.6L LH2 V8, Petrol
Center bore
70.3 mm
Bolt pattern
5x115
Thread
M12 x 1.5
Check price on Amazon · 235/50R17 Wheels 17x8 ET51 · 5x115 · 70.3 mm on Amazon
Tire sizeRim size and bolt patternPressure, psi
235/50R17 95VRim 17x8 ET51 5x11530 psi
235/50R18 97WRim 18x8 ET51 5x11530 psi
235/40R19 93WRim 19x8.5 ET50 5x11532 psi
245/40R19 95YRim 19x9 ET45 5x11532 psi

How to read 95V: 95 is the load index (up to 1,521 lb / 690 kg per tire) and V the speed rating (up to 149 mph / 240 km/h). ET51 is the wheel offset: how far the mounting face sits from the rim centre, in millimetres.

USA

2 trims
STS 3.6i 302 hp · 3.6L LY7 V6 235/50R17 95W / 255/45R17 95W 4 fitments
Generation
GM Sigma ll · 2008–2012
Market
USA
Power
302 hp
Engine
3.6L LY7 V6, Petrol
Center bore
70.3 mm
Bolt pattern
5x115
Thread
M12 x 1.5
Check price on Amazon · 235/50R17 Check price on Amazon · 255/45R17 Wheels 17x7.5 ET51 · 5x115 · 70.3 mm on Amazon
Tire sizeRim size and bolt patternPressure, psi
Front235/50R17 95WRim 17x7.5 ET51 5x11530 psi
Rear255/45R17 95WRim 17x8 ET51 5x11530 psi
Front235/50R18 97WRim 18x8 ET51 5x11530 psi
Rear255/45R18 97WRim 18x8 ET51 5x11530 psi
Front245/40R19 97YRim 19x8 ET45 5x11530 psi
Rear275/35R19 99YRim 19x9 ET45 5x11530 psi
235/50R17 95VRim 17x7.5 ET51 5x11530 psi

How to read 95W: 95 is the load index (up to 1,521 lb / 690 kg per tire) and W the speed rating (up to 168 mph / 270 km/h). ET51 is the wheel offset: how far the mounting face sits from the rim centre, in millimetres.

STS 4.4i 469 hp · 4.4L LC3 V8 255/45R18 97Y / 275/40R19 100Y 4 fitments
Generation
GM Sigma ll · 2008–2012
Market
USA
Power
469 hp
Engine
4.4L LC3 V8, Petrol
Center bore
70.3 mm
Bolt pattern
6x115
Thread
M12 x 1.5
Check price on Amazon · 255/45R18 Check price on Amazon · 275/40R19 Wheels 18x8.5 ET51 · 6x115 · 70.3 mm on Amazon
Tire sizeRim size and bolt patternPressure, psi
Front255/45R18 97YRim 18x8.5 ET51 6x11530 psi
Rear275/40R19 100YRim 19x9.5 ET56 6x11530 psi
Front255/40R19 95YRim 19x8.5 ET51 6x11530 psi
Rear275/40R19 100YRim 19x9.5 ET56 6x11533 psi
Front255/40R19 95YRim 19x9 ET45 6x11532 psi
Rear285/35R20 97YRim 20x10 ET45 6x11535 psi
255/45R18 97VRim 18x8 ET51 6x11530 psi

How to read 97Y: 97 is the load index (up to 1,609 lb / 730 kg per tire) and Y the speed rating (up to 186 mph / 300 km/h). ET51 is the wheel offset: how far the mounting face sits from the rim centre, in millimetres.

What these columns mean
Rim size
Rim diameter × width in inches, and the factory offset (ET) in millimetres, e.g. 18x7.5 ET25.
Bolt pattern (PCD)
Number of studs and the diameter of the circle they sit on. It must match exactly.
Center bore
Diameter of the hub hole. Larger aftermarket bores need hub-centric rings.
Pressure
Recommended cold inflation pressure for that axle, in psi.
Staggered
A wider tire on the rear axle than the front. Front-to-back rotation is not possible.
Thread size
Lug bolt or nut thread — needed when buying aftermarket fasteners.
Trims sold in 2009
4
Generation
GM Sigma ll sold in 2 market versions
Other years
All years (2004–2012)

Considering a different size?

Compare your current tire size with the one you want: diameter change, ground clearance and speedometer error.

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