Question on tire PSI

[Sin City Trail Boss]

Quick question, the sticker on the door jamb that has the recommended PSI, is that for every day driving, or under a load?

 

Mine has it recommended at 41 PSI, but at that PSI my ride is too bumpy. 

 

2019 Trail Boss with 18" wheel.

[davester]

The owners manual will have the answer to your question.

[lt1z]

The 18” wheel recommends 41 but the 20” wheel recommends 35 psi on the AT4/TB

[newdude]

The Duratrac they use is an LT275/65R18 C load tire, hence the 41psi in the door jamb.  GM sets the placard pressure for mileage, tire wear and payload.  You can probably lower it some, but more than 7% or so lower than the door tag will trip the tire light.   

Edited July 30, 2019 by newdude

[Fuelie]

10 hours ago, davester said:

The owners manual will have the answer to your question.

Actually my owners manual says refer to the sticker in the door jam.

Tom

[aseibel]

16 hours ago, Sin City Trail Boss said:

Quick question, the sticker on the door jamb that has the recommended PSI, is that for every day driving, or under a load?

It is for normal driving based on cold tires. You could get by with a little less, at the compromise of a bit faster tire wear and worse fuel economy. Are you looking at cold readings or after driving? Temperature changes account for several pounds during the day.

 

I keep mine at the posted psi or 1-2 higher. But my 18's only ask for 35 psi. There are 100 variables that go into it, you'll have to see what works best for you. 

[Sin City Trail Boss]

19 minutes ago, aseibel said:

It is for normal driving based on cold tires. You could get by with a little less, at the compromise of a bit faster tire wear and worse fuel economy. Are you looking at cold readings or after driving? Temperature changes account for several pounds during the day.

 

I keep mine at the posted psi or 1-2 higher. But my 18's only ask for 35 psi. There are 100 variables that go into it, you'll have to see what works best for you. 

Yes I always go by cold PSI. That much I know.

 

Just seems like 41 is excessive, but it is my first time running C rated tires. 

 

My friend who works at Discount Tire said the recommend tire pressure is for under a load but it sounded like BS to me.

[Sin City Trail Boss]

7 hours ago, newdude said:

The Duratrac they use is an LT275/65R18 C load tire, hence the 41psi in the door jamb.  GM sets the placard pressure for mileage, tire wear and payload.  You can probably lower it some, but more than 7% or so lower than the door tag will trip the tire light.   

I've actually lowered mine all the way down to 32 psi for off roading and it didn't trip the light.

[redwngr]

4 hours ago, Sin City Trail Boss said:

Yes I always go by cold PSI. That much I know.

 

Just seems like 41 is excessive, but it is my first time running C rated tires. 

 

My friend who works at Discount Tire said the recommend tire pressure is for under a load but it sounded like BS to me.

I believe your friend at Discount Tire is correct.

 

Pressure on the door is at the full load the vehicle is rated for when using the tire size that is on the sticker (meaning the size it was born with)

 

Cold pressure, of course.

There are load vs pressure tables out there. 

They always recommend higher pressures at higher loads.

 

Dealer can (but not all will) set the TPMS levels to suit needs. 

 

Edited July 31, 2019 by redwngr