I have a 2019 M3P and I have always run it with the tyre pressures set to 42 psi when cold as per the manual. However, the other day I noticed that the tyre pressure screen under Services is recommending 39 psi front and 40 psi rear. The message is in tiny print and may have been present for months before I noticed it. I have been very happy with the current settings of 42 psi all round and getting pretty even tyre wear after doing tyre rotation between the front and rear. Now I'm confused as to what pressures I should be using.
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Tyre pressures recommendation on screen
- Thread starter AMP_it_up
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What does it say in the app?
teslamotorsclub.com
Tyre Pressures and warnings
This topic must have been a coincidence, as I pumped up all 4 tyres this morning (added ~4 psi) as I had noticed the pressure were going down (TeslaFi report) and I didn't want to get any warnings as I've got a long drive later today! It was a chilly one in our neck of the woods Thu thru Fri...
teslamotorsclub.com
spooksman
Member
I have a 2020 M3P, I posted this on another thread earlier - says 44psi when cold...
Why does the tyre pressure quoted vary? Obviously, a car on 20" wheels will require different pressures to those on 18 & 19" wheels, but for example, my car is a 2019 LR on 18" wheels and currently its suggesting 37psi in the app, however I've seen it 'request' 41/42psi at times.
Why the variance?
Why the variance?
It's either a software bug or they keep changing their mind!
Tyre pressures are always a compromise as there are lots of variables involved e.g. temperature, grip/traction, road surface, road conditions, speed, load etc. In reality there is no such thing as a singular optimum cold pressure for all situations, so manufacturers come up with a safe value - which is nearly always on the high side of what would actually be optimum for both ride and handling in most daily conditions.
Now maybe the App is trying to be cleverly pro-active in suggesting a cold pressure based on your historic pressure data and current ambient conditions. Or maybe it is just a bug!
Just checked mine out of curiosity (2022 MY LR) and the App is recommending the standard 42 psi. I'm actually running 38 psi cold because I can
Don't know how Tesla do it, but on our other car the recommended pressure changes as you drive to cater for the tyres warming up. 42psi at ambient temperature might be 45psi when you've driven it for an hour. This is helpful because if you stop to fill the tyre, the cold/ambient pressure is obviously not what you want, you want more as the tyre is warm.
Now whether Tesla are trying to be cleaver using the cameras to work out what the temperature of things (a thermometer would be too simple) and maybe getting it wrong, I don't know, but it should never suggest below the ambient pressure.
Now whether Tesla are trying to be cleaver using the cameras to work out what the temperature of things (a thermometer would be too simple) and maybe getting it wrong, I don't know, but it should never suggest below the ambient pressure.
spooksman
Member
If it adds a data point, the pressures on my screen shot were yesterday evening, and I have an M3P on Performance 20" wheels. That was 44psi recommended for cold.
MrBadger
Badger out
Graham J
Member
Well you know humans can figure out the exact temperature with their eyes so cars should be able to do it too.
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