Couple of psi lower tire pressure on the long road trips?

[litesong]

Originally Posted by Wolf359
....I think you just got used to the ride feeling like rocks or truck tires, no give at all.......I remember the tire store filling my tires up to 40 PSI once, the car rode like it had rocks for tires, you could feel every pothole.
Might be something to what you say. For 35 years, I drove small cars. I like the their surety of handling & traction, specially since I've raised my accustomed tire pressures to 40PSI. I now have a "larger than my normal sized" car. & I would hate it, if it felt like it was wallowing on too soft tires.

 

[MoneyJohn]

Thank you everyone for the comments.

Originally Posted by Miller88
The last trip I took I had the tires inflated to 80PSI*. My Subaru, however, seems to have a really low recommended pressure. 29R,30F. I usually run 33,34.



*I was towing a 7000 pound trailer 500 miles.

Really? Its same on our '15 Forester. Only once the mechanic put 32psi on both and DW complained that it feels like the car has wooden wheels.

 

[litesong]

Originally Posted by JohnnyJohnson
Lowering tire pressure all you're doing is giving away MPG.
Lots of people mention that low pressure tires create more heat. The extra heat is created by extra burned gasoline that lowers MPG. Well, how 'bout dat.

 

[SwampSurvivor]

Originally Posted by MoneyJohn
Thank you everyone for the comments.

Originally Posted by Miller88
The last trip I took I had the tires inflated to 80PSI*. My Subaru, however, seems to have a really low recommended pressure. 29R,30F. I usually run 33,34.



*I was towing a 7000 pound trailer 500 miles.

Really? Its same on our '15 Forester. Only once the mechanic put 32psi on both and DW complained that it feels like the car has wooden wheels.


Oh mine definitely rides very rough when I run them up to 33,34. I can definitely understand why they're rated so low.

Honestly, once I am out of warranty I am going to drop to 16s and run a 215/70-16 or 225/65-16 HT or touring tire. The ride is so, so, so much better on 16s with more sidewall.

 

[Pew]

Originally Posted by litesong
Lots of people mention that low pressure tires create more heat. The extra heat is created by extra burned gasoline that lowers MPG. Well, how 'bout dat.


Less pressure = more friction = more heat, not to do with the engine.

Originally Posted by RDY4WAR
I'll remember your post, if I drive to mountain pass elevations to 7000 to 14,000 feet. I'm a featherfooter tho, so my top speeds of 60-65MPH(not 80+MPH), should also be a factor to avoid over-inflated tires.


You'll be fine, just don't inflate it like a balloon and expect no consequences like most normal daily commuters.

 

[litesong]

Originally Posted by Pew
Less pressure = more friction = more heat, not to do with the engine.
Not quite. The extra unnecessary friction & heat generated in the tires shows the engine is working harder (less MPG), not only to move the vehicle, rotate the drivetrain & turn the wheels/tires, but to provide the NECESSARY energy to generate the UNNECESSARY tire friction & heat.

 

[Pew]

Originally Posted by litesong
Originally Posted by Pew
Less pressure = more friction = more heat, not to do with the engine.
Not quite. The extra unnecessary friction & heat generated in the tires shows the engine is working harder (less MPG), not only to move the vehicle, rotate the drivetrain & turn the wheels/tires, but to provide the NECESSARY energy to generate the UNNECESSARY tire friction & heat.


Right, the lower MPGs yes but strictly speaking the tire temps have nothing to do with the engine working.

 

[Lubener]

Originally Posted by MoneyJohn
Yesterday, while coming back after a long weekend, I noticed at least 4 cars with tire blowouts. The first time in my life saw 16-wheeler tire blow out. It was not even that hot yesterday. That made me wonder if one should reduce the tire pressure a couple of psi if you are going on a long road trip.

I am pretty sure the tires get hot on a long drive but I always thought that the tires are made to handle that heat. I admit I don't know the physics of it in relation to the tires.

Is there any consensus on how it should be dealt with in summer, stick to the pressure indicated on the door or reduce a bit? We usually take 15 min stops every 2 hours, but this year we are planning first long (~1200 miles) road trip, thought I should know.




Low pressure causes excessive heat. Like Ron Popeil used to say, "set it (door placard) and forget it".