Check Your Tire Pressure!

[Doug_G]

Another forum member just PM'd me about his tire pressures. Seems when he had his TPMS reset done the pressure in all four tires came up ten pounds low. I had the same experience.

I hadn't checked my tires because I knew that Tesla had inflated them properly, and even watched them recheck the pressures after they installed the winter wheels on my car. Unfortunately there's one catch - it's winter! The wheels were installed and checked indoors. My TPMS wasn't working because the tool wasn't available when I picked up my car.

Tire pressures drop when the temperature drops. You need to adjust your tire pressures seasonally, to maintain the same cold inflation level.

If your TPMS hasn't been synchronized with your wheels for whatever reason, please check your pressures! Do this when the car has been sitting outside in seasonal temperatures for a couple of hours.

Tesla recommends 45 psi for the Pirellis, but you can run them as low as 40. A bit lower pressure might provide better traction, while the higher pressure would give you better range.

 

[FlasherZ]

Good points, Doug. Also, it should be noted that there are differences between TPMS warnings. "Tire Pressure Low" means that the car is getting a read from the sensors and that they're reporting low pressure. "Service TPMS System" or similar means something else (in my case two of the sensors were defective), and likely require reprogramming.

 

[JakeP]

Just as a datapoint, I checked mine upon delivery with my fancy new Longacre Racing 50406 tire inflation gauge (thanks for the recommendation, Jerry33!), and they were all spot-on at 45PSI, temps in the mid40s and the rubber cold.

 

[mknox]

Tire pressures drop when the temperature drops. You need to adjust your tire pressures seasonally, to maintain the same cold inflation level.

Good advice regardless of car brand. During last week's cold snap I got my 12v compressor out and had to add over 5 PSI to all the (cold) tires on all my cars.

 

[jerry33]

A bit lower pressure might provide better traction

That's a pretty big might there. Winter traction is tricky and 15 minutes later on the same road can make a big difference because conditions can change rapidly. In general lower pressure will put more tread blocks on the ground increasing the traction in deep snow. High pressure will squeegee the water off of the ice or packed snow and give better traction because the tire will be touching the surface rather than just the film of water that is over the ice or packed snow. Most winter driving is over packed snow and ice rather than deep snow unless you drive on a lot of rural roads.

Lowering the TPMS value so that it won't alert isn't the solution I would recommend.

 

[spatterso911]

Just as a datapoint, I checked mine upon delivery with my fancy new Longacre Racing 50406 tire inflation gauge (thanks for the recommendation, Jerry33!), and they were all spot-on at 45PSI, temps in the mid40s and the rubber cold.

Any advantage to getting the liquid filled gauge "Longacre" 50403 compared to the other models?

 

[jerry33]

Any advantage to getting the liquid filled gauge "Longacre" 50403 compared to the other models?

Not really. Liquid filled gauges are good when placed in areas with high vibration because they dampen the indicator movement.

 

[Doug_G]

I have a Longacre, but only because the cheap units kept breaking on me.

(The last time one broke on me, the only place open was Walmart. The gauge I bought there was branded "Slime". Seriously!)

 

[wycolo]

I have a Longacre, but only because the cheap units kept breaking on me.

(The last time one broke on me, the only place open was Walmart. The gauge I bought there was branded "Slime". Seriously!)

LOL!! I bought a SLIME too, a $50~ clip-lead 12v portable compressor. Took it home & tried to inflate a flat tire- would not work, NADA. Returned it for a refund and ordered online (from WalMart !!) a bigger 12v compressor ($85) that *did* work. But the green Slime motif was kinda cute.
--

 

[brianman]

ordered online (from WalMart !!) a bigger 12v compressor ($85) that *did* work.

Pic or link?

 

[SteveH]

Are digital gauges more or less accurate than the old standard gauges? Is there a particularly accurate gauge out there?

 

[Doug_G]

The Longacre gauges are pretty accurate and durable.

I haven't found the digital gauges to be any better or worse... the one I had was annoying to use and broke just as quickly as any other cheap gauge.

 

[jerry33]

Are digital gauges more or less accurate than the old standard gauges?

Digital just refers to the readout. It has nothing to do with the accuracy. Digital gauges can be very accurate, but typically you're talking two or three times the price for the same accuracy.

Is there a particularly accurate gauge out there?

Yes, for $1000 plus accessories. Here are two good quality gauges: Model 50406 and model 50404.

 

[alset]

Agreed that some things are best left analog...

I generally use Accu-Gage products and they work well for < $15 - click the "by Accu-Gage" to see all the options. I've tested AccuGage results against other more expensive gauges (I also have a LongAcre gauge for my race car) and they are very accurate.
Accu-gage Tire Pressure Guage - 60 PSI Range Straight Angle : Amazon.com : Automotive