Encore Tire Pressure

[mnmjackson]

Sorry if this has been covered, but I couldn't find a thread. What is the correct tire pressure for the 18 inch tires? The sticker on the door reads 35 pounds, but On-Star and the Buick app says my tires are between 48 and 50 psi, which is acceptable. I usually follow what the door sticker reads, so this is odd. I haven't yet looked at the tire itself (sorry if I should have done so first) but I usually trust the door sticker. 35 psi sounds awfully soft...

Thanks!

Mike

 

[ljmattox]

Wow, ~50lbs? Um, no. I run mine at 35, and that's how Buick set them too, the last time I had service.

 

[IceMan2]

35 is soft..??...while 48-50 is more acceptable?? Sorry..but that's just crazy. The wife runs around 35 in her 18" tires on the Encore. I run the same in the 20" tires on my new Impala as well.
Don't you have tire sensors with a read out on your DIC..?? That should tell you if they are low.
IceMan2

 

[MelsRegal]

buy a digital tire gauge and set the tire pressure after the vehicle has sat overnight to the pressure listed on the door sticker. If you mean by "Buick App" the factory tire pressure monitoring system, it only triggers for low pressure and same for On-Star it notifies for low pressure only. Someone is over inflating your tires.
http://www.amazon.com/Accutire-MS-4...pebp=1438024017804&perid=0X8HSNMGKTN75EBBZ68P

 

[mnmjackson]

Thanks for the advice. I thought it strange, but that's what the Buick dealership set them at. I will lower them to the more manageable 35 pounds. I knew you could tell me the truth!

I don't recall seeing tire pressure on the DIC readout, but I have only looked at it as I'm driving. I'll see what it says.

Thanks again.

Mike

 

[IceMan2]

Thanks for the advice. I thought it strange, but that's what the Buick dealership set them at. I will lower them to the more manageable 35 pounds. I knew you could tell me the truth!

I don't recall seeing tire pressure on the DIC readout, but I have only looked at it as I'm driving. I'll see what it says.

Thanks again.

Mike

The DIC will tell you the current air pressure in each tire. At least it does on my Wife's premium Encore.

 

[gralm]

The DIC will tell you the current air pressure in each tire. At least it does on my Wife's premium Encore.

It does the same in my BASE as well. I thought it was supposed to warn you when pressure is lower than 35psi, but it did not happened with my car.

 

[MelsRegal]

The pressure has to be significantly lower than 35 PSI for the system to warn you. Normal driving and air temperature changes can account for up to 3 + or - from a set temperature. I would say it would have to drop below 30 before the warning occured.

 

[KSDeputy]

Yesterday on the highway on the way to an appointment I got a warning message saying my right rear tire was down to 28 lbs. I took the Encore to the dealer. They took the tire off, could find no leak, and put it back on. The warning disappeared. I have had the car for two years, no problems at all until this. I suspect a glitch in the warning system. I will continue to drive it and see if it happens again. Buick has a longer bumper to bumper warranty than the Chevrolets, found that out yesterday.

 

[rfruth]

Yesterday on the highway on the way to an appointment I got a warning message saying my right rear tire was down to 28 lbs. I took the Encore to the dealer. They took the tire off, could find no leak, and put it back on. The warning disappeared. I have had the car for two years, no problems at all until this. I suspect a glitch in the warning system. I will continue to drive it and see if it happens again. Buick has a longer bumper to bumper warranty than the Chevrolets, found that out yesterday.

Sounds like the warning system did just what it was supposed to (if the dealer properly inflated the tire(s))

 

[Foursoors]

I had a Honda that would throw TPWL every now and then for no reason. I just took it in and they reset it and it would go away. No big deal. Those systems are extremely sensitive and they can get thrown off now and again.

 

[DocDee]

I have a 2017 Encore. This past winter I received low pressure warnings on all tyres. I used the not very accurate pump gauge to inflate them to as close to 35/36 as possible. Afterwards, the digital display read 37 or 38 on the tyres. When I took it to the dealer for first service at 7200 miles, they took the pressure down to a displayed 35 all round.

 

[LARRY70GS]

The correct tire pressure depends on the tires currently on the car. The door sticker applies to the tires that came with the car. Modern tires commonly are higher pressure, look at your sidewalls. 44 and 51 psi tires are very common today. I run 85-90% of the maximum cold inflation pressure listed on the sidewall. I have 51 psi tires on my 98 Riviera. I run 43 psi. The car rides great. My door sticker says 30 psi. The tires that originally came on my car were 35 psi maximum.

 

[MelsRegal]

this appears to be a topic that is debated on car forums quite often. In cases where you are dealing with cars that were manufactured in the 60s and 70s the tire pressures were for bias ply tires and often were in the mid 20's. When installing a modern radial on those older cars you typically want a minimum of 30 and some people go with 32. This particular thread started in 2015 and the original OP's tire were over inflated. Going by the tire pressure listed on the sidewall is generally not recommend by major tire retailers such as Tirerack. I'm curious on the 98 Riviera if you have actually tried to get a visual footprint of the tire thread or have driven 10k miles or more to see whether a wear pattern has developed.

 

[LARRY70GS]

I have had those tires on my 98 for about 5 years and 30,000 miles. They look great as far as wear goes, nice and even. If I inflate them to 30 psi, the handling becomes very mushy, and my gas mileage suffers. I believe tire rack does not have this right. There is a lot of misinformation out there about tire inflation IMO. There is absolutely no reason why you can't inflate a tire to the maximum cold pressure. It may ride overly harsh, but wear and reliability should be fine. In any case, it can't hurt to try my suggestion, then judge for yourself. In the case of a late model car no older than 2-3 years, I would use the tire placard recommended pressures. My 98 originally came with 35 psi max tires. Buick recommended 30 psi all around. The 51 psi Yokahama Avid TRX tires definitely need more pressure. That is my personal experience, yours may vary..

Tires are rated by load capacity. Manufacturers suggest an inflation pressure to handle the load on each tire position on that particular car model. The tire sidewall will list a maximum pressure at a maximum load. AFAIK, the load quoted on the tire has not changed, but the pressure has. In other words my Yokohama tires support the same max load at 51 psi that my OE tires supported at 35 psi. That tells me that I need more pressure than 30 psi in that tire.

 

[MelsRegal]

Using your method of calculating tire pressure, percentage of maximum PSI on side wall, the formula would be vehicle weight divided by maximum load for 4 tires multiplied by the maximum tire pressure on the side wall. I found a vehicle weight of about 3,700 pounds for a 98 Riviera. I found a Y rated tire in 225/60x16 with a 51 psi max and a load rating of 1653/tire. The load rating for 4 tires is 6612. 3700/6612= .56. Multiply the 51 PSI by 56 = 28.53 PSI which we both agree is too low. Running 85% to 90% of the maximum pressure applied to the maximum load would give you a figure for a vehicle weight of close to 6,000 pounds. I cannt see how you apply your percentage to the PSI only and ignore the load specified for that PSI. Another way to look at it is if the original tire had a maximum pressure of 44 PSI and you went to a 51 PSI that's a 16% increase in PSI. Multiply the factory pressure of 30 PSI by a 16% increase and you only get about 35 PSI. As I said before this topic is beaten to death on many car forums and I think you can raise the OEM tire pressure maybe 4 pounds but I think 13 pounds is too much but again you are proof that it can be done.

 

[LARRY70GS]

I understand the math Mel, I just think there is more to it than that. Don't know what that is, LOL, but all I know is that the director of my car club, one of the best mechanics I know advised me when I got my tires, to run 45 psi in them. He told me the new tires need more air. Like I said, when I use 30 psi, the handling and gas mileage are adversely affected. 43 psi gives me an awesome ride. I have Cooper Cobra radials on my 70 GS. They are 44 psi tires. I found through trial and error that 37 psi work the best in them. My 70 Chassis manual specifies about 24-26 psi, but of course that car came with Bias Ply tires. 85% of the max pressure seems to be the sweet spot. Try it, it's reversible if you don't like it.

 

[adamcar]

I have no doubt you can run pressure up to the max cold psi on the tire. But does your center tread wear more quickly than by using a more common 30-35 psi? I would think it would but depends on tire and vehicle and rotation patterns I guess.

 

[LARRY70GS]

I have no doubt you can run pressure up to the max cold psi on the tire. But does your center tread wear more quickly than by using a more common 30-35 psi? I would think it would but depends on tire and vehicle and rotation patterns I guess.

I'm not advocating filling it to the maximum. If you have the Encore, go by the door sticker. If you want to see if the tire is overinflated, simply wet the tread and run it onto dry ground. Then look at the tread pattern left. You'll see if it is full or narrower.

 

[MelsRegal]

Another factor is the road conditions. Hitting a pot hole with a tire inflated to 30 PSI tire and than hitting that same pot hole with a tire at 43 PSI will be significantly different. At 30 PSI the sidewall flex will absorb some of the energy but at 43 PSI that sidewall is really stiff and the impact will be passed on significantly more to your struts/shocks and other steering components, not to mention you and your passengers . There are pros and cons to both pressure settings.