spender

OK, I'm a stickler about certain things, and tire pressures are one of them. I figure that anything that is important enough to merit prominent display on a vehicle's VIN door pillar sticker is worth sticking to religiously.

However, I've now had a variety of vehicles going back to a few Isuzu Troopers, a Lexus LS430, and now a Porsche Carrera 4S. The last 3 cars I've had have all had different air pressures between front and rear tires. However, without exception, whenever I pick it up from the dealer after a service, they've always screwed them up!

On my Porsche for instance, I know that the fronts get inflated up to 36, and the rears are at 44, whether they are snows or regular tires. I had my snow wheels/tires put on yesterday at a shop that is known as "THE" Porsche tire shop here in Calgary. When I checked the tires cold this morning, the fronts were at 36 - but so were the rears! I adjusted the rears up to 44 and the ride felt better right away.

So, my question is, is tire pressure really that important? If yes, why can't dealers, etc. get it right?

Zookie

36-44psi is FULL LOAD, 2 Passengers and Full Luggage... Actully according to TSB its 43 rear...

According to 997 TSB Half Load (2 Passenger no Bags) is 33f and 36r...

Edit: this is for 18" and 19" Summer and Wnter Tires... I Believe 17" Pressure is Lower...

Barn996

Maybe they were used to working on 17"s, then 36lbs F/R would be correct.

okbarnett

look on the tire for the max pressure. Stay below that and allow 3-5 lbs for extreeme heat and pressure increase on long trips, keeping the tire well inflated will keep it more square on the wheel and keep the alignment and geometry more consistant

Shark Attack

LOL.. this gets good around 55 seconds in and Fits this thread at 1:45
http://www.youtube.com/watch?v=ygbL6YUFqN8

sjfehr

No. Sorry, but overinflating your tires like this is as dangerous as underinflating; if you overinflate, grip decreases and will cause you to take longer to stop and you'll lose control (over/understeer) at slower speeds in turns.

Porsche knows what they're doing. They pressures they spec are the "sweet spot" that maximize both grip and safe and predictable handling. If you're just streeting your Porsche, stick with the numbers on the door. The only reason to ever deviate is on the track.

spender

Thanks Zookie - where is this TSB you speak of for the 996?

VGM911

+1
I don't have my owner's manual here in the office, but as I recall...36F/36R is correct, as Barn says.

soverystout

+1

And to our Canadian friends, 36/44 is the correct cold PSI for 18 inch rims.
What is this FULL LOAD you speak of?

Zookie

you already "quoted" my Answer in your post...