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Discussion Starter · #1 ·
Just for my own information, are the TPM systems built into the latest vehicles user adjustable? I have heard that the OEM setpoint is based on the manufacturers recommended tire pressures. As the majority of us agree, to run an empty truck with 80psi in the rear tires is dangerous (I run at 50 psi), which means that the TPM will always show an alarm condition therefore providing me with no indication if pressures are below 50 psi.
I see that there are aftermarket TPM systems that enable the user to adjust the set point. For those of us that tow 5th wheels, it would seem that the OEM TPM system is useless.
I understand that the OEM system can be adjusted by your friendly GM dealer who has the necessry tools and equipment, namely a Tech II. So when trailering, it is no problem! After arriving at the campsite uncouple the trailer, go to the nearest GM dealer, deflate the tires to 50 psi, pay the dealer $90 to reset the setpoint. Before leaving the campsite, go back to the dealer, inflate the tires to the towing pressure and pay him another $90 to reset the setpoint again.
On a six week trip to Arizona from the frozen North, we stay at about 12 different sites, thus the cost would be about $2000 in dealer fees. Cheaper to buy your own Tech II, even cheaper to buy an aftermarket adjustable TPM system.
 

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Why do you have to do it more then once? I set my low today to 45psi all the way around and will just keep it there forever. No more alarm for me.

I do not think you need to constantly reset them?
 

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Why do you have to do it more then once? I set my low today to 45psi all the way around and will just keep it there forever. No more alarm for me.

I do not think you need to constantly reset them?
HUH?

railbuff, I don't think he read your post or he's not aware of load/inflation tables for tires.
 

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I guess I do not understand? I just had my TPMS set down to 45psi to all tires by the dealer. I assumed that means the 45psi is the low and not the baseline of where it needs to be at all the time? I figured that if I go up to 80psi for load I might get a warning for high pressure, but I only tow once a month at max and can deal with the alarm on trips.

I understand the load tables, but I am not real familar with the TPMS system. Let me know if I misunderstand something please.

Thanks!
 

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I found out today that the alarm will go on when the pressure hits about 70psi with your threshold set at 45psi. I guess I need to make the threshold a bit higher, maybe in the 50-55 range. That should hopefully cover me when I am towing and when I am not. I am assuming you have about 15-20% to play with. Anyone know for certain? Which aftermarket TPMS that have a high and a low setting work with our system?
 

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Discussion Starter · #7 ·
If you are running with no load in the truck bed, 80 psi is in my opinion and in the opinion of the tire manufacturers, dangerous because only a portion of the width of the tire will be in contact with the road. This can initiate skidding when the brakes are applied, or wheel spinning when accelerating harshly. Also, with these higher pressures, the walls of the tire will be very stiff which agravates bouncing when hitting a bump in the road.
We should bear in mind that the tire is the main component of the primary suspension on a vehicle, secondary suspension is provided by the leaf springs on the rear and the torsion bars on the front. By over inflating for the load being supported by the rear tires will stiffen the primary suspension and result in a rougher ride and more road shock to the vehicle.
 

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what is the tire inflation on the side of the tire,,[mine says 80 psi] from the manufacturer
 

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It is 80 max with full load. Running that with no load makes me bounce everywhere. I usually run about 50-60psi empty.

what is the tire inflation on the side of the tire,,[mine says 80 psi] from the manufacturer
 

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Discussion Starter · #10 ·
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