Over-inflated tires
Feb 25, 2018, 5:20 pm
#3
Join Date: Mar 2016
Posts: 1,884
Many (most?) cars ship from the manufacturer with overinflated tires. I have read that it is done to help prevent flat spotting the tires when parked for an extended time during transport. Especially when strapped down on a ship/train/truck, the tension on the straps significantly increases the static load on the tires. When a new car is delivered to a dealer, setting the tires to the proper inflation is supposed to be part of the "pre-delivery check".
I have noticed that a significant number of the rental cars I have driven were overinflated, and just assumed that they didn't check it.
I have noticed that a significant number of the rental cars I have driven were overinflated, and just assumed that they didn't check it.
Feb 25, 2018, 11:15 pm
#4
Original Poster
Join Date: Oct 2016
Posts: 3,703
Many (most?) cars ship from the manufacturer with overinflated tires. I have read that it is done to help prevent flat spotting the tires when parked for an extended time during transport. Especially when strapped down on a ship/train/truck, the tension on the straps significantly increases the static load on the tires. When a new car is delivered to a dealer, setting the tires to the proper inflation is supposed to be part of the "pre-delivery check".
I have noticed that a significant number of the rental cars I have driven were overinflated, and just assumed that they didn't check it.
I have noticed that a significant number of the rental cars I have driven were overinflated, and just assumed that they didn't check it.
Feb 26, 2018, 7:04 am
#6
FlyerTalk Evangelist
Join Date: Jun 2001
Programs: DL 1 million, AA 1 mil, HH lapsed Diamond, Marriott Plat
Posts: 28,190
- that cold pressures not exceed the max molded on the tire's sidewall
- that pressures are adequate to carry the load of vehicle and cargo at expected speeds and ambient temperatures
40-45 psi might leave you with a stiff riding car. It may well not be outside of requirements.
Feb 26, 2018, 12:19 pm
#7
Join Date: Nov 2014
Location: MCI
Posts: 698
Interesting as I had similar experience after renting at OGG. PSI were reading about 44-45 on all 4 tires on the infotainment screen.
I know higher PSI usually means better MPG in general. No idea why specifically they inflate to 40+....but I'm happy to get a bit more MPG out of it though
I know higher PSI usually means better MPG in general. No idea why specifically they inflate to 40+....but I'm happy to get a bit more MPG out of it though
Feb 26, 2018, 1:26 pm
#8
Join Date: Mar 2016
Posts: 1,884
Interesting as I had similar experience after renting at OGG. PSI were reading about 44-45 on all 4 tires on the infotainment screen.
I know higher PSI usually means better MPG in general. No idea why specifically they inflate to 40+....but I'm happy to get a bit more MPG out of it though
I know higher PSI usually means better MPG in general. No idea why specifically they inflate to 40+....but I'm happy to get a bit more MPG out of it though
Feb 26, 2018, 3:34 pm
#9
FlyerTalk Evangelist
Join Date: Mar 2004
Location: SGF
Programs: AS, AA, UA, AGR S (former 75K, GLD, 1K, and S+, now an elite peon)
Posts: 23,194
I've never heard of a lawsuit (at least covered in Auto Rental News, anyway) against a rental agency due to overinflated tires, so I don't think the liability for traction is on anyone's minds. (That might change if a customer ever wins a lawsuit on that basis.) As for wear, the rental companies generally don't keep the cars long enough for that to be a factor--by the time it's even close to time to replace the tires, the cars are typically long gone from the fleet.
Feb 27, 2018, 8:15 am
#10
Join Date: May 2012
Location: STL
Posts: 130
That's interesting info. But I've seen cars that are not brand new be over-inflated. In fact I was at National recently and was about to pick a car when an employee took it away. The guy helping people on the lot said he was just going to inflate the tires. I waited for him to come back and he had inflated the tires to 45 psi. So it must be intentional.
-Tires were over inflated from the manufacturer for shipping reasons, etc. and not corrected upon introduction to the fleet
-The porters added air to the tires and did not have a tire gauge and just visually check to make sure the tires look inflated. These people are paid close to minimum wage and have to move cars in and out very quickly and do not have time to make sure each tire's PSI matches what's listed on the driver's door
-The car came from a cold climate and the air expanded in the current warmer climate giving a higher PSI
It might be different in Europe, but rental agencies in the US aren't combing over rental cars before they put them in the fleet. Maybe they should, but I've certainly never had that expectation. If you watch the people turning over they cars, they just get them processed in as fast as they can.
Feb 27, 2018, 1:49 pm
#11
Join Date: Apr 2004
Location: BOS
Programs: Marriott LTG, HHonors Diamond, Nat'l Exec
Posts: 3,581
-The porters added air to the tires and did not have a tire gauge and just visually check to make sure the tires look inflated. These people are paid close to minimum wage and have to move cars in and out very quickly and do not have time to make sure each tire's PSI matches what's listed on the driver's door
Feb 27, 2018, 9:41 pm
#12
Original Poster
Join Date: Oct 2016
Posts: 3,703
They are absolutely not intentionally over inflating tires. There are so many variables, but National or any rental agency has no reason to purposely over inflate tires. Likely scenarios for over inflation are:
-Tires were over inflated from the manufacturer for shipping reasons, etc. and not corrected upon introduction to the fleet
-The porters added air to the tires and did not have a tire gauge and just visually check to make sure the tires look inflated. These people are paid close to minimum wage and have to move cars in and out very quickly and do not have time to make sure each tire's PSI matches what's listed on the driver's door
-The car came from a cold climate and the air expanded in the current warmer climate giving a higher PSI
It might be different in Europe, but rental agencies in the US aren't combing over rental cars before they put them in the fleet. Maybe they should, but I've certainly never had that expectation. If you watch the people turning over they cars, they just get them processed in as fast as they can.
-Tires were over inflated from the manufacturer for shipping reasons, etc. and not corrected upon introduction to the fleet
-The porters added air to the tires and did not have a tire gauge and just visually check to make sure the tires look inflated. These people are paid close to minimum wage and have to move cars in and out very quickly and do not have time to make sure each tire's PSI matches what's listed on the driver's door
-The car came from a cold climate and the air expanded in the current warmer climate giving a higher PSI
It might be different in Europe, but rental agencies in the US aren't combing over rental cars before they put them in the fleet. Maybe they should, but I've certainly never had that expectation. If you watch the people turning over they cars, they just get them processed in as fast as they can.
Mar 9, 2018, 5:42 pm
#13
Join Date: Mar 2018
Posts: 3
This happens often with Hertz, I carry a small digital tire gauge for this reason.
One thing to note, while not good, overinflated tires are better to have than underinflated tires. Tires can easily handle an extra +10 psi over the recommended cold pressure amount, they’re not going to explode.
Handling will be a little weird and the tire will certainly wear out the tread faster, but it’s no where near is as bad as driving -5 psi or more under inflated.
One thing to note, while not good, overinflated tires are better to have than underinflated tires. Tires can easily handle an extra +10 psi over the recommended cold pressure amount, they’re not going to explode.
Handling will be a little weird and the tire will certainly wear out the tread faster, but it’s no where near is as bad as driving -5 psi or more under inflated.
Mar 9, 2018, 9:32 pm
#14
Original Poster
Join Date: Oct 2016
Posts: 3,703
This happens often with Hertz, I carry a small digital tire gauge for this reason.
One thing to note, while not good, overinflated tires are better to have than underinflated tires. Tires can easily handle an extra +10 psi over the recommended cold pressure amount, they’re not going to explode.
Handling will be a little weird and the tire will certainly wear out the tread faster, but it’s no where near is as bad as driving -5 psi or more under inflated.
One thing to note, while not good, overinflated tires are better to have than underinflated tires. Tires can easily handle an extra +10 psi over the recommended cold pressure amount, they’re not going to explode.
Handling will be a little weird and the tire will certainly wear out the tread faster, but it’s no where near is as bad as driving -5 psi or more under inflated.
Mar 9, 2018, 11:21 pm
#15
Join Date: Mar 2016
Posts: 1,884