JohnDoe2

When I got my TL it had some vibration and the dealer replace all four tires. I didn' t notice much difference but was happy to get new tires.

When my 30,000 mile service came due, I decided to change the cabin filter and air filters myself and goto a budget oil change outlet to save money. All my other services were done at the dealer.

While they were checking the car out, the kid announced the tires were at 40 psi! Ain't that a bit high? I hadn't been driving more than a mile so I knew it wasn't the heat.

Do you think dealers are deliberatly overinflating tires to mask the tire flat-spotting problem?

Thorin78

The manual says 32psi on all 4 tires for Auto and 35psi for fronts on 6spd.

So maybe the kid has a bad tool or something. I don't think the dealership would do it on purpose as I don't think over inflating a tire fixes flat spotting.

subinf

Air pressure tools are pretty unreliable. Even if it wasn't on point, I don't think the dealer would purposely overfill a tire.

Will Y.

Agree ^^^. Air pressure gauges at repair facilities and gas stations are notoriously inaccurate. That's also why I checked air pressure on each new car I got the morning after purchase-- the variations were incredible on a Camry we got-- every tire was a different pressure, too.
Otherwise, service personnel often set all four tires at the same (usually improper) pressure on every vehicle on purpose so they don't have to remember pressure differences between different vehicles like the MDX, TSX, etc. And yes, it would take only a couple of seconds to check the door plate, but that isn't what they do.

ndx2

when you drive the car, the air in the tire gets heated up and expands, therefore the pressure increases... check it when it's "cold" for a more accurate reading.

2xselectrak

If you look in the door jam you will see the correct pressure, the front and rear are different

subinf

Read the original post very carefully. The OP already stated that was most likely not the issue.

enormus

I had the opposite occur on my last visit to dealer. 32psi all around, but I have the 18" A-spec wheels that call for 39 front / 36 rear. Bottom line: always check it yourself and always follow the sticker.

JohnDoe2

I can see a car owner having a cheap tire pressure guage that is not accurate.

But I would expect service departments to have accurate tools.

subinf

They start out accurate, but they get beat on pretty bad. They are expensive to maintain/replace. Most of the shops that I used to work at would replace every year. While I never calibrated the outgoing gauges, I'd bet they were 3-4psi off. Not really a big deal as it doesn't make that much of a difference.

Will Y.

Today, I was at the gas station that I usually use. Station had just installed a shiny new air hose and integrated brass gauge, which measured high by 6 psi per my certified round gauge, when I put air into the minivan's tires.

pohljm

I think that the dealer just missed reducing the tire pressure from the factory, they are shipped with 40+ psi to reduce the flat spotting while in transit. they should have reduced them when they received it and did there new vehicle prep

mlody

Exactly – my car PSI was all over the board. Had to wait next day and measure cold PSI to accurately set it. All the wheels were over inflated which was easy to adjust without going to a gas station

1995hoo

I usually check mine within a few days of getting it back from the dealer because I assume they will forget that the fronts should be 3 psi more than the rears. Seems like they usually put them all at around 30 psi. But at least they've never done a rotation and left the rears at 35 and the fronts at 32. I'd find that more annoying because bleeding off the extra air is a nuisance. Adding air is easy since I keep a compressor around. Talk about unreliable gauges, BTW, the built-in gauge on that thing reads about 10 psi higher than my hand-held digital one.

Desert_TL

When I took delivery of my new 06 TL, the TPMS indicated that the tire pressure was about 40psi on each tire. I think they come from the factory a tad overinflated. This will cause the suspension to seem a little stiffer and the handling will be a little better. They probably overinflate from the factory so that if the car is test driven, the tight suspension/handling will be more pronounced. If the tires were 30psi or lower, the handling might seem more spongy than they like. I think they prefer to shoot for overinflation than underinflation.

Either way, I took delivery and the car had 17 miles on it. I'm up to about 5300 now (*tear*) and the tires are down to about 30psi. In fact when I start the car in the morning when it's pretty cold, the TPMS indicates an average inflation of about 27 PSI and the warning light comes on. After about 3 minutes of driving the tires warm up and it goes up to about 30 PSI, and the warning light turns off. All of the tires "deflated" at the same rate. That is they were all 40 PSI when I took delivery and now they're all equally down to 30 PSI.

I personally wouldn't worry about the tires being slightly overinflated to 40PSI. I think it's far worse to have the tires underinflated. Underinflated tires hurt your gas mileage, cause excessive heating in the tire sidewall, and cause decreased handling performance (too spongy). Overinflated tires will mainly only cause uneven tread wear. Right?

mcafee_jones

My 2006 TL's tires were set at 40psi when I got the car from the dealer too. It was explained that since the cars were sitting on the lot and might not possibly be driven for awhile, the tires might flatspot, so that's why it was set at 40psi. He said I could leave it at 40psi and it wouldn't hurt anything or reduce it down to spec for a softer ride.

Will Y.

Overinflation will increase noise, reduce resistance to impact damage and might cause some handling over-sensitivity if the overinflation is extreme, i.e. more than 40lbs. If there is something hinky about the tire(s), wheel balance, suspension or alignment, overinflation may cause or accentuate spooky/erratic handling and ride too.
You will want to maintain the differential between front and rear tires to keep understeer (plow) within stock limits. Otherwise, oversteer will increase as the rear tire pressures increase in relation to front tire pressures.

Jesstzn

Overinflation will also cause excessive center tread wear.

BTW it was the old nylon tires that used to flat spot sitting .. they may do it more to reduce flex in the tie downs due to sidewall flex.

Set your tire all winter in the basement in one spot .. it won't flat spot .. I stored my cars from Nov to April all the time .. no flat spot ..

Dealer is shitting someone.

northwoods

the recommended tire pressure settings on your car are NOT
necessarily the proper settings for the tires...

manufacturers like to recommend a lower tire pressure to
achieve a 'smoother' ride....

many a gear-head will tell you to run at 80% of the tire's
"maximum allowable pressure"

i know the MXM's are 50 lbs "maximum"....so 40 lbs would be 80%

i ditched my MXM's for Yoko's, but i run 38 psi.....

groovyone789

mine new car came from the dealer at 39psi, while i was cleaning the car, i checked the recommended pressure....... 35front 32rear. i let some air out, rides a bit different but i don't see 40psi hurting the car either, its not much of a difference to me

ltcjmb

https://acurazine.com/forums/showpos...5&postcount=40

ubnpast

I have my snow tires at 40 in the front, the sidewall is soo small that I dont want to bent a rim, plus the tire is really soft, so it isnt really supportive.