Tire pressure

[Warrantero]

All four of my tires were set to 50 psi and my spare was set to 55 psi. I was wondering why on the drive home from the dealer why the ride felt very stiff.

Why is the dealer not checking this simple item ? In the Toyota’s I have purchased before I received a checklist on everything the dealership inspected prior to me driving away in the vehicle.

I have my 30 day check up next week, see how that goes.

I figured that the “LEXUS” experience would be better. Time will tell.

Luxury + Nebula Gray

 

[Sean950054]

Why Automakers Sometimes Overpressurize Tires And How That Can Affect Your Handling: Ask An Engineer​

• By Huibert Mees
• May 2, 2022
• 3:00 pm
• 67 Comments

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Hello Autopians and welcome to another edition of Ask an Engineer. This week I thought we could talk about tires again since we had so much fun with them the other week.
A reader named Patrick asked me a question about recommended tire inflation pressures. He had just recently bought himself a shiny new Jeep Gladiator, and when he first took it on the highway it just didn’t feel right to him. It was sensitive to wind and drafts from passing semi trucks. It followed road grooves excessively, and he felt the handling was actually pretty scary.

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When he checked the Tire Pressure Monitoring System reading it showed all four tires inflated to about 41-42 psi while the recommended pressure is 37 psi. When he pulled off the highway and adjusted pressures back to the recommended levels, the difference was instantly noticeable. The truck rode better, the cross winds didn’t bother it so much, and overall it handled like he expected from a vehicle of this type.
What might have happened here? How can the tire pressures in a new vehicle be so much higher than the factory recommendations?

Why An Automaker Might Over-Pressurize Its Tires Before Sale​

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One possibility might be that the dealer prep on this vehicle was not performed correctly. Many OEM’s will ship their cars from the factory with much higher than normal tire pressures. This helps to prevent flat spotting which can happen in any tire when a car that sits in one place for a long time, like on a transporter or in a storage lot. The tire develops a flat spot where it contacts the ground and will create a thump-thump sound as you then drive it. In most cases the flat spotting will disappear after driving for a few miles, but in extreme cases it can completely ruin a set of tires. I have seen some OEM’s inflate their tires as high as 50 psi to help prevent flat spotting and part of the dealer prep is to reduce the pressures back down to the factory recommended levels before the car is delivered to the customer.

 

[Warrantero]

Thanks!