And maybe all tires... I have the 20 inch wheels and the Bridgestone Alenza's or something close to that word. I read that they should be 32 lbs cold. Then I got to thinking. What temperature cold? It's 41 degrees here today so what temperatureis GM's idea of cold. I drove for about 10 minutes when I hit the air supply. I put it up to 35 lbs from 27 lbsand it eventually got up to 37 lbs after about an hour of driving. What's a common sense view on tire pressure. I can't imagine if it was 74 degrees out that it wouldn't have hit 42 lbs. once it warmed up and would have started a lot higher. In fact cold weather was the first time I got warned about tire pressure by the onboard computer.

Thanks.. G..

 

The pressure is always lower when its cold, every winter the damn things go crazy in the morning when I start up the Tahoe, but usually are fine after a bit of driving. I always try to keep mine around 34psi. Typical winter temps in SW Washington are low to mid 40s.

 

A while back, ZX recommended 33 psi at ambient.

 

Cold means after being parked for at least an hour or driven less than one mile. Check your pressure then. It's the heat that builds up as you drive that you are trying to avoid at the time of testing. Cold pressure of 33psi must beobtained under the aboveconditions. Yes if the temp drops, like it has, you will have to add air but you must maintain 33psi for the existing cold (as described above) conditions.

 

Then what is the most pressure you ever want to see once it's warmed up?

 

I agree...33psi to 34psi cold pressure gives a very nice ride. Of course, when I got the car it had 36psi cold and both times I went to a dealer, they jacked it up to 36psi again....they love using their air compressors.....

 

Usually there's a max pressure on the sidewall of the tire.

 

The max pressure on the sidewall is also a "cold figure" even though "cold" can be a very large temperature range; just go with it.

When you fill the tire only pay attention to "COLD” (as in: vehicle has not been driven overnight and is parked in the shade) inflation pressures and do not confuse the matter by trying to calculate the tires "hot” pressure.

You should not exceed the recommended inflation pressure found on the "Tire and Loading Information” sticker in the driver's door jamb by more than about 10% or in the Tahoe's case 3-4psi, you should also never allow your tire pressure to go below the recommended pressures found on the decal in other words; consider the sticker the "Lowest Allowable Operating Pressure”.

Another important factor is to make certain that the pressures on aach axle are as close to exactly the same as possible and in the Tahoe's case (where all 4 tires call for the same pressures) make sure that all 4 tires are identical and do this using a high quality and known accurate pressure gauge not the TPMS read-out as this system uses four different gauges in effect.

Merry Christmas.

Dave

 

Since I am still running the stock Bridgestone tires, does the recommended cold pressure of 32-33psig still stand for after market 20x8.5 wheels? I would think so, but just want to double check. I was running 33psig cold with stock 20" wheels and now have 35psig cold in stock tires (Bridgestone) on new wheels and can definetely feel the rougher ride.....assuming I can drop tire pressure back down to 33psig cold with no problems??

 

You can drop down to 30psi without any problem and it will improve your ride.