Tire Pressure

[Skeeter29]

What tire pressure do you run?

[txab]

https://www.gm-trucks.com/forums/search/?q=tire pressure&type=forums_topic&nodes=240

[kylant]

55/50

 

had the dealer reduce my thresholds to 55

no lights, no warnings

Edited September 19, 2020 by kylant

[FirstAscent]

TLDR; don’t go by what others set theirs at unless you know you have the same tire size and load rating.


Full Version:
I’ve always gone by whatever my expected vehicle axle weights are that match up on the tire load and inflation tables.

https://www.toyotires.com/media/3729/application_of_load_inflation_tables_20200723.pdf

This table is independent of tire brand, it’s based on tire size and load rating (E rating, F rating etc)

It will tell you how much weight your tire size can support at a given psi.

Example, if the actual weight (not how much your axle can support) on your front axle was 5000 lbs, then look up your tire size and find what psi supports at least 2500 lbs (2500 lbs each tire for 5000 lbs weight on axle)

If your weights fluctuate (different number of people in vehicle etc, then play it safe me just go up in psi), and if you tow, you should be doing this anyway and know what your weights are, especially on your rear axle!

I have two pressure settings I switch between: normal driving and towing.

I have one trailer and I know what my worst case scenario fully loaded is so that’s the pressure I set to.

[shadow gray 2020 hd]

Still at the pressures they were when I picked up the truck at the lot, +/- 60 front 70 rear.  Those are the placard specs for my truck.

[6.6HD]

i drop it around town to 55 all the way around.

 

60/70 when towing.

[gSwift]

On 9/19/2020 at 9:29 AM, kylant said:

55/50

 

had the dealer reduce my thresholds to 55

no lights, no warnings

What kind of strings did you have to pull to get your thresholds lowered? My truck is in for the first service and I asked them to lower mine and the shop manager said it can't be done. I'm starting to think they are very incompetent 

[newdude]

1 hour ago, gSwift said:

What kind of strings did you have to pull to get your thresholds lowered? My truck is in for the first service and I asked them to lower mine and the shop manager said it can't be done. I'm starting to think they are very incompetent 

 

 

It's not an incompetence issue.  GM says no, dealers must abide.

 

Quote

 

#PIT4506E: Questions Regarding Reducing Tire Pressures - (May 13, 2020)

Subject: Questions Regarding Reducing Tire Pressures

 

Supersession Statement

This PI was superseded to update model year. Please discard PIT4506D.

 

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Correction

Some owners of HD Trucks and Utilities may ask if they can lower their tire pressures from what is recommended on the "Tire and Loading Label" if the vehicle is not being used for hauling or towing.

Recommendations / Instructions

The answer is no. Tire pressures being set to the "Tire and Loading Label" will ensure the safe handling and ride characteristics of the truck. Ride, handling, tire wear, fuel economy, and road noise concerns may be caused by improperly adjusted tire pressure.

Note: If the tire pressures are lowered on a vehicle equipped with Tire Pressure Monitor, the "Check Tire Pressure" message may display on the DIC. The Tire Pressure Monitor system was implemented to meet FMVSS 139 and cannot be removed or disabled. 

 

 

Edited October 20, 2020 by newdude

[gSwift]

3 hours ago, newdude said:

 

 

It's not an incompetence issue.  GM says no, dealers must abide.

 

 

Okay, I can understand that. Guess I just need to find one of these dealers that these other guys are using to get it done or is there a programming tool available for purchase so I can do it myself?

 

And the incompetence comment is much deeper than just the tire pressure comment. After this trip i'll be finding a new servicing dealer.

[newdude]

15 hours ago, gSwift said:

Okay, I can understand that. Guess I just need to find one of these dealers that these other guys are using to get it done or is there a programming tool available for purchase so I can do it myself?

 

And the incompetence comment is much deeper than just the tire pressure comment. After this trip i'll be finding a new servicing dealer.

 

No way to DIY it.  Dealer will be the only ones (or possibly an AC Delco shop that has the same tools) that can do it.  Its all a part of the BCM programming/setup procedure.  

[newdude]

UPDATE:  https://www.gm-trucks.com/forums/topic/244286-wams-t1-bcm-programming-is-here-speed-limiter-delete-idle-timer-increase-customized-lighting-options-and-way-more/

 

WAMS just announced their T1 BCM spec programming.  Perhaps you might have an alternate now for this, but I don't know if it supports the HD trucks as well.  They support adding/disabling, but not sure about custom pressure settings.  

 

https://www.whiteautoandmedia.com/product/t1-pickup-wams-spec-bcm-programming/

Edited October 21, 2020 by newdude