New tires, TPMS and tire pressure

[buddy guy]

I'm getting new tires Tuesday to replace the SRA's. While still a passenger type tire (not LT) they do have a higher max pressure rating than the SRAs (SRAs are 44, new ones are 51). So I guess a few questions:

If the new tires are run at say 45lb vs the 39 lb on the door jamb for the SRA's, will the TPMS learn that new tire pressure or see an error and need a manual reprogramming? Or will the sensors "learn" the new pressure if higher (truck is ram 1500)

Should the new tires be run at 39ish like the SRA's (I've always been told you should run a vehicles tires at the vehicle recommended specs for optimum performance. In this case not adjusting for towing or heavy load)

 

[MADDOG]

It will read the higher pressure but you won't be running them at max pressure so you should still be within the allowable PSI zone for your truck.

Run the tires at whatever PSI feels best that won't over or under inflate your tires, wearing out the center or outside ribs too quickly.

Here is a good method to use to see how your inflation numbers are working out:

 

[JohnnyMac]

I ran my new 35x12.5r20's at what the door recommended and lost 4 to 5 mpg. I recently bumped them up to about 44lbs and gained 2+ mpg's back and have better performance, cornering etc......My TPMS sync'd right up and no alarms.

 

[buddy guy]

Thx so much for this guys. I didn't have any idea what the margin is for these sensors. I know I've blipped up to 43 I think and no alarms.

Sent from my SM-N960W using Tapatalk

 

[JB1]

Thx so much for this guys. I didn't have any idea what the margin is for these sensors. I know I've blipped up to 43 I think and no alarms.

Sent from my SM-N960W using Tapatalk

Do the TPMS even send a warning for too much psi or do they only work for low psi?

I know the threshold is 20% from the HD owners threads

 

[buddy guy]

I wonder this too because i've read lots of references regarding low pressure but not high. We need someone running a LT tire at much higher pressure to comment!

Sent from my SM-N960W using Tapatalk

 

[MidwestExpress]

I wonder this too because i've read lots of references regarding low pressure but not high. We need someone running a LT tire at much higher pressure to comment!

Sent from my SM-N960W using Tapatalk

I've run mine at 50psi cold (load range E) and no pressure indicator came on. Pretty sure it's only triggered by too low pressure.

 

[BobSacomano]

I'm getting new tires Tuesday to replace the SRA's. While still a passenger type tire (not LT) they do have a higher max pressure rating than the SRAs (SRAs are 44, new ones are 51). So I guess a few questions:

If the new tires are run at say 45lb vs the 39 lb on the door jamb for the SRA's, will the TPMS learn that new tire pressure or see an error and need a manual reprogramming? Or will the sensors "learn" the new pressure if higher (truck is ram 1500)

Should the new tires be run at 39ish like the SRA's (I've always been told you should run a vehicles tires at the vehicle recommended specs for optimum performance. In this case not adjusting for towing or heavy load)

Your truck won't object to 45. I went out and bought a cigarette-lighter pump that you can preset the PSI to keep my tires at good pressure all the time, and just toss the pump under the seat.

 

[ram1500rsm]

You can manually check how much psi you need
https://www.toyotires.com/media/2125/application_of_load_inflation_tables_20170203.pdf

Also the min PSI threshold is preset for a base 39psi in your case, so filling your tires with more air doesn't affect the min threshold. The alarm is tripped from the base PSI minus 6-7 PSI so it wouldn't matter if you pump your tires at 39 or 80, the logic uses that base PSI value to make the calculation.

If you need to change the base, you can use AlphaOBD

 

[buddy guy]

You can manually check how much psi you need
https://www.toyotires.com/media/2125/application_of_load_inflation_tables_20170203.pdf

Also the min PSI threshold is preset for a base 39psi in your case, so filling your tires with more air doesn't affect the min threshold. The alarm is tripped from the base PSI minus 6-7 PSI so it wouldn't matter if you pump your tires at 39 or 80, the logic uses that base PSI value to make the calculation.

If you need to change the base, you can use AlphaOBD

Thx for the info. I don't have alpha or intend to buy at this point...so thats a good bet of info here. I won't be so far off the 39 that I'm concerned

Sent from my SM-N960W using Tapatalk