The Automotive Thread

Professional Engineer & PE Exam Forum

Help Support Professional Engineer & PE Exam Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Filling your tires with Nitrogen is BS.  

First of all, air is 78% Nitrogen in the first place, so ideally, you'd only be replacing 22% of Oxygen and other trace gases.  

Second, it is nearly impossible to purge all of the air out of the tire before re-filling with Nitrogen, so there will still be a couple of percent contamination with other gasses.  At best, you are increasing the concentration of Nitrogen in the tires by 20%.

Finally, the N2 molecule is 300 pm in diameter, while O2 is 292 pm in diameter.  That ~3% difference in molecule size is going to make very little difference in the permeability of the gas through the rubber, and if you have a leak somewhere in the valve stem or tire seal, it will make no difference at all.

 
Filling your tires with Nitrogen is BS.  

First of all, air is 78% Nitrogen in the first place, so ideally, you'd only be replacing 22% of Oxygen and other trace gases.  

Second, it is nearly impossible to purge all of the air out of the tire before re-filling with Nitrogen, so there will still be a couple of percent contamination with other gasses.  At best, you are increasing the concentration of Nitrogen in the tires by 20%.

Finally, the N2 molecule is 300 pm in diameter, while O2 is 292 pm in diameter.  That ~3% difference in molecule size is going to make very little difference in the permeability of the gas through the rubber, and if you have a leak somewhere in the valve stem or tire seal, it will make no difference at all.
You pretty much listed my thoughts but most people's eye start to gloss over when I get into a chemistry lesson so I didn't go there

 
The truck has tire pressure sensors, but I shut them off with the tuner.  I got an error message one day saying a sensor was bad.  You can recalibrate them, but that involves deflating the tires one by one and then reinflating them.  And that's assuming you just have a sensor that got "lost" by the system.  The other down side is that, being an F350, Ford says the tire pressure is supposed to be up at 80psi.  That's great if you're carrying a load, but the ride is nicer if you lower it down to ~60psi which is low enough to set off the alarms.

 
I pay the few extra bucks for nitrox in my scuba tanks because it shortens me intervals between dives, but I wouldn't squander $ putting it in my tires..

 
I have multiple dead sensors.  The batteries in them are rarely good for 3 years it seems.  I just ignore the light since its not needed to pass inspection.

 
can someone tell me the purpose of this setup?

I see this all over town?  Isn't the purpose of having a truck to carry shit in?

not my photo , cant ever get the camera out in time when I see something similar???

56756-testrack04.jpg


 
To look like a chode.

 
Last edited by a moderator:
Mine looks exactly like that...except it was about half the price.
Dee Snider from Twisted Sister had Counting Cars customize his Tesla S.  They gave it some nice paint graphics and new wheels.  They admitted they had no idea about the mechanicals of the car and during the show Dee was screwing with them by making the car do things using the cell phone app while the car was in the shop.  It was likely staged but pretty funny.

Snider-tesla.jpg

 
Back
Top