Pontiac · Grand-Am · Bar

Recommended bar for a Pontiac Grand-Am

Drivetrain: front-wheel drive
Body: passenger car
PSI F / R: 32-35 / 32-35
Bar F / R: 2.2-2.4 / 2.2-2.4

bar

2.31 / 2.31

32-35 / 32-35 psi · 231 / 231 kPa

32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa

European and UK handbooks usually quote bar. The Pontiac Grand-Am catalogue is 2.2-2.4 bar front and 2.2-2.4 bar rear (midpoint 2.31 / 2.31). A 10 °C overnight drop takes roughly 1 psi (0.07 bar) off a closed Pontiac tyre.

Bar, PSI and kPa

Bar-led conversions around the Pontiac Grand-Am. 2.2-2.4 bar is not “32-35 divided by ten”.

Bar	PSI	kPa
2.07	30	207
2.21	32	221
2.28	33	228
2.31	33.5	231
2.41	35	241
2.48	36	248
2.62	38	262
2.76	40	276
3.03	44	303
3.45	50	345
4.14	60	414

Pontiac Grand-Am placard versus sidewall

If the Pontiac sticker is painted over, the handbook is next. This website is a map, not a replacement VIN label.

Estimated pressure by tyre size (185/65R15 and others)

Planning cold pressures for sizes often seen on a passenger car. This Grand-Am sample opens with 185/65R15, then 215/55R16 and 225/50R17.

Tyre size	Front PSI	Rear PSI	Front bar	Rear bar	Front kPa	Rear kPa	Note
185/65R15	33	33	2.28	2.28	228	228	Small / older car
215/55R16	34	35	2.34	2.41	234	241	Slightly wider 16-inch
225/50R17	35	35	2.41	2.41	241	241	Touring 17-inch
205/60R16	34	34	2.34	2.34	234	234	Taller 16-inch
225/45R17	35	35	2.41	2.41	241	241	Sport 17-inch
195/65R15	34	34	2.34	2.34	234	234	Very common compact
245/40R18	36	36	2.48	2.48	248	248	Wide touring 18-inch
205/55R16	34	34	2.34	2.34	234	234	Typical mid-compact OEM

Load notes

Load moves the rear of a passenger car first. If the factory placard already has a “laden” column, use that instead of these sketches.

Condition	Front (est.)	Rear (est.)
Driver only	34 psi / 2.34 bar	34 psi / 2.34 bar
Full occupancy	34 psi / 2.34 bar	35 psi / 2.41 bar
Motorway + luggage	35 psi / 2.41 bar	37 psi / 2.55 bar

How to set the Grand-Am

Measure before the school run, not after the M25.
Write LF / RF / RR / RL. Do not keep Grand-Am numbers in your head.
Add air in short bursts toward 34 psi (2.31 bar) front and 34 psi rear.
If one corner is 4 psi down, hunt for a nail before you blame the weather.
Log date, ambient temperature and the four readings.

Temperature drift

Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this Grand-Am.

Ambient	Gauge (front mid)	Bar	kPa	Note
−5 °C (hard frost)	31 psi	2.14 bar	214 kPa	Gauge reads low; do not overfill once warm
0 °C	32 psi	2.21 bar	221 kPa	Gauge reads low; do not overfill once warm
8 °C (UK winter morning)	33 psi	2.28 bar	228 kPa	Gauge reads low; do not overfill once warm
20 °C (set cold here)	34 psi	2.34 bar	234 kPa	Baseline
30 °C	36 psi	2.48 bar	248 kPa	Do not bleed a hot tyre
38 °C (heatwave tarmac)	37 psi	2.55 bar	255 kPa	Do not bleed a hot tyre

Pontiac notes

No special Pontiac exception: the Grand-Am uses the door-pillar placard. Size estimates on this page only help if you have left the original load index behind.

Spare and inflator kit

A matching full-size spare on the Pontiac Grand-Am usually follows the higher axle (often the rear, near 32-35 psi). A space-saver is commonly 60 psi / 4.1 bar — read that tyre’s own sidewall. An inflator kit is not a spare; check the sealant date.

Keep the Pontiac Grand-Am on the printed band; use 185/65R15 and 225/50R17 only as a map for non-OEM wheels.

Other Pontiac models

Catalina Safari Bonneville G6 Grand-Prix GTO Vibe Montana Sunbird

Questions about this Grand-Am

What tyre pressure should a Pontiac Grand-Am use?

Catalogue reference is 32-35 psi front and 32-35 psi rear (2.2-2.4 / 2.2-2.4 bar), cold. Confirm on the door-pillar placard.

Front versus rear on the Pontiac Grand-Am?

This row is 32-35 F / 32-35 R. Even when they match, a laden rear can justify a higher number if the sticker prints one.

When does TPMS warn on a Pontiac Grand-Am?

Direct TPMS typically flags about 25% below placard — near 25 psi on this row. Fill to the sticker, not to the lamp.

How often should I check a Grand-Am?

Monthly, before a long trip, and after a 10 °C weather swing. Include a full-size spare.

Is the sidewall number correct on a Pontiac Grand-Am?

No. Sidewall PSI is a maximum. The Grand-Am placard is the operating target, near 32-35/32-35 psi.

Handbook: placard · bar vs PSI · front vs rear · cold inflation