So I'm showing my G/F how to use the MFD, and when I showed her the Tire Pressure screen, I was surprised to see all pressure over 40lbs.

I checked the manual and it says 32lbs if memory serves...then I check the tire sidewall, and it said Max pressure 42 or 44(can't recall exactly)

My question is...which is correct?

 

32 PSI is correct. If you look at the sticker on the driverside when you open the door it staes 32psi cold pressure front as well as rear. The #s on the tire are the maximum pressure. I dont go by the mid because theycan be off and always use the same tire pressure guage and set them in the morning after the vehicle has sat all night. After driving depending on outside surface and air temperature they usually run about 3-4 psi higher.

 

My G/F mentioned this when she took the car in to get the Bodyside moldings installed...they just said oops and fixed it.

 

As long as one is under the tires rated pressure(when warmed up) you aren't going to do anything except make the ride a little more harsh.

Mike

 

Driving with the wrong inflation pressure also results in uneven wear of the tires. Overinflated tires will show more wear in the center of the tread and underinflated tires towards the edges.

 

While that is true, I would imagine that would be inflation over pressure recommended on the physical tire, not the vehicle.

Mike

 

my tire pressure indicator is on when I first drive and after 15 minutes it goes off,it must be just on the edge!

 

Maybe you should add air? I take it you have a base model.

Mike

 

When I drove my RDX off the dealer lot, the tire pressure was showing at 38 on all four tires. I figure the dealer must have over-inflated them on purpose. Why they would do that I am not sure.

I drove it that way for a week because honestly I was fixated on all the 'cool' stuff. But then I brought the psi down to 32psi. It did make a little difference in the ride (for the better).

 

Dealers often over-inflate tires because:

A) the cars may be sitting for long periods, slowly bleeding down pressure
B) over-inflation tends to sharpen handling on test drives
C) the vibration of a bent wheel can be masked by high tire pressure (this mostly applies to used cars)
D) the people hired to do simple prep work may not be working toward their Masters. The complexity of a tire gauge may lead them to use the TLAR method (That Looks About Right).

It's a good idea to bring a quality tire gauge and check all four tires before a test drive. It exasperates salesmen but I have found wildly differing pressures on the same car. One varied from 45 psi to 70 psi. This was a used car with bent wheels. It was fun to watch the salesman stammer through an explanation.

Never use the sidewall pressure; it is a max limit. I have even seen tire shop guys mistakenly pump up to the sidewall limit.The recommended pressure will be on a placard around the doors or fuel door.

The recommended pressure is a baseline for cold tires and should be set in the morning at least once a month. Your cold tire pressure will change with the ambient temp by about 1 psi per 10 degrees F, so Spring and Fall can have dramatic effect.

As the tires heat up during driving they will gain 2 to 4 psi. You can watch this on the MID w/ Tech.

A few psi under-inflation causes sluggish emergency handling, poor fuel economy and stresses the sidewalls. A few psi over reduces lateral grip on curves and in braking, increasing stopping distance.

Everything, EVERYTHING is riding on a few square inches of tire contact patch. This is why TPMS is being mandated.

If you look both ways before crossing the street and always wear your seatbelt then check your tires once a month.

 

so if I were out driving for a while and stopped at a gas station to check the tires and put some air in them, should I expect the psi to be 2-4 higher than normal due to the tires being heated up?

 

You should always check your tire pressure cold before driving. Mine range from 33-39 depending on if I have driven on them and the weather outside.

 

The RDX is manufactured in the US, right? Marysville?

If so, I don't know what the practice is for the RDX which has a shorter distance to travel, but for vehicles manufactured in Japan, the dealer told me they pump up the tires to 45-50 lbs for the trip over to prevent flat spotting, and the dealer is supposed to, as part of the delivery process, adjust to recommended inflation, just like pulling off the plastic from the seats, and the body, etc.

 

I'm assuming you picked the car up recently. Acura ships the cars with the tire pressure set between 40psi and 50psi, they do this to avoid "flat spotting" the tires when they are strapped down to transport vehicles. Your dealer forgot to adjust them.

 

Yeah, it's gotta be a dealer by dealer thing - doubt anyone is doing that on purpose. I bought my truck last weekend and they were set to 32psi cold - so someone already took care of that for me.

 

Ya but my only way to put air in the tires is at a gas station, then the tires aren't cold there since I've been driving to get there. I actually checked them all today while getting gas and they were all at 34 psi

 

You can check them when cold just to see if you need air or not. If you do need air, then just add air later when at a gas station. Add plenty of air, then release air at home when cold to get an accurate reading.

 

Or you could also get a cheap air compressor at Target or someplace for under $30. Takes longer, but it can be done at home. It is also better than nothing when you have a slow leak to get you to a repair place.

 

Yes a good suggestion. I carry one in my vehicle all of the time. Unless you have a full blow out it should be good enough to fill with air to get you somewhere that you can get it fixed.

 

I keep an air compressor in the car as well, but it's a bother to get out and put away so I keep a $10 bicycle pump in the garage for adding a pound or so when temperatures drop.

 

I already get made fun of because I am so anal about tire presure. If I buy the RDX and can look at it all the time, I will drive myself batty.

I have one of the Target compressors at home. Works fine. Plus you can use it to inflate kid's balls, etc.

 

Just checked mine and they were all dead on 32 psi....will have to get a compressor soon though