Tire pressure conflict

honda
cr-v

#1

I purchased 4 Nokian WR tires for my 2003 Honda CRV. The dealer instructed me to keep them inflated to 35 psi. The Honda sticker on the door jamb says to inflate tires to 26 psi. This a large difference. I’m confused .Who do I listen to. I’m totally confused. Thanks in advance.


#2

Tire shops routinely inflate tires to 35 psi these days, and we had a post very similar to yours just the other day. Another CRV if I remember correctly. 35 psi will probably give you slightly better fuel mileage, but may result in a ride that’s stiffer than you like.

The tires were inflated to 35 psi in the shop, which is significantly warmer than the outside temperature. If you check the tires now they might be closer to 30-32 psi.

This happened to me just last week when I had new tires installed. The shop inflated them to 35 psi, although my car specifies 32 front and 29 rear.

I checked the tires over the weekend and they were all around 32 psi. I then adjusted the pressures to my preference, which is 34 front and 32 rear. In a few weeks the ambient temperature will probably be lower and I’ll check and adjust them again.

I prefer to stay a few psi above the manufacturer’s recommendation for the slight mileage increase and a little crisper handling response, but that’s just me. Another benefit is it keeps the tires from being under-inflated, which is very bad.

It’s up to you how you inflate the tires. It is, after all, your car. I’d leave the tires alone for now, unless you think the ride is too stiff, in which case lower the pressures a bit.

Just don’t EVER let them get below 26 psi, which seems ridiculously low to me. If you reduce the pressure to 26 psi now you better get in the habit of checking the tires every few weeks, because as the temperatures drop so will the pressure, and the tires will be under-inflated before you know it.


#3

Split the difference and try 32 psi…


#4

If these tires are the same size as the original ones that came on the CR-V when it was delivered from the factory, then you should stay as close as possible to Honda’s inflation specifications. If you are not sure if the size is the same, you will find the original tire size on that door jamb placard along with the recommended pressure.

This being said, many people–me included–inflate our tires to 3 or 4 lbs over the car mfr’s recommendation. The increased pressure will slightly improve tread life, handling, and fuel economy, and will slightly degrade the ride quality. If the slightly harsher ride does not bother you, I would recommend the slightly higher pressures. However, I think that the dealer’s reoommendation is excessive.


#5

We get this question a lot.

When new tires are installed, you want to run the tire pressures at what the door placard reflects. This way you get an idea how the vehicle rides and handles at those pressures. Once that baseline is determined, then you can adjust the tire pressures up a couple of PSI at a time to see how effects the ride and handling of the vehicle. A point may be reached where the tire pressures result in a harsher ride than desired.

Tester


#6

The owner’s manual probably states the tire pressure recommendations and then says something like to increase the pressure if the vehicle is heavily loaded … yadda yadda.

In this case I think the 35 psi is too high, and the Honda recommended sounds too low. If these are pretty big tires on a relatively small and light vehicle the 26 psi could be correct. I 2nd Tester’s concept of drop the psi to the Honda recommendation and see how the CRV rides and handles. Then try 28 psi, and perhaps 30 psi and compare the ride and handling.

Too much pressure can make the “contact patch” on the road too small and result in poorer traction. If it were my car I’d probably run between 28 and 30 psi.


#7

+1.

Also make sure to rotate these tires on a timely basis. They are very all-season good tires especially in winter conditions. However the only downfalls beyond price is you need to keep with regular rotations or they get noisy.

I have owned 4 sets on 3 cars.


#8

Listen to Tire-Shop-Guy as he explains things after you ask HIM why the difference. He does this for a living day after month after year after decade. He knows what he is doing and has nothing to gain by misleading you (and everything to lose).


#9

…or he could also be wrong.

Don’t forget, occasionally you will find tire shops will mount 2 new tires on the front wheels of cars, despite the fact that every major tire manufacturer states that if only 2 tires are purchased, the new ones go on the rear.


#10

No offense intended but your post made me chuckle. I only wish it were true. Too many times, I have caught them making mistakes. Like the time I got new tires for my truck and they only put 32 psi in them. They’re supposed to have 60 psi. No one at that shop knew any better and it wasn’t a mom&pop operation. Just one example.

From what I’ve seen, not many people are content to spend their entire working life in the retail tire business. Most of them appear to be younger and have less experience than you suggest.

The OP is following a rule I strongly believe in; trust but verify.


#11

They’re supposed to have 60 psi.

I assume this was not OEM size tyres? I can’t think of a passenger car today that calls for anything close to 60 psi. You are not looking at the tyre sidewall are you?


#12

Joe

Twin Turbo did tell us that these were truck tires.
I don’t think that 60 psi is at all unusual on many types of truck tires.


#13

Yea, I must have missed that.


#14

The car-manufacturers determine the advice-pressures with use of the formule of the tire-organisations. I have been busy with making spreadsheets for calculating tire-pressure, with use of the formule of the European tire assosiation ETRTO wich goes down to 21 psi. Recently found out that the American TRA used up to 2005 formula with the same setup but another power in it, so came to lower pressures, so warmer tires and flatter tires. For that reason they had to stop at 26 psi otherwise the tire side wall gets to warm and the tire gets damaged.
http://cid-a526e0eee092e6dc.skydrive.live.com/browse.aspx/.Public/Recalculating%20tyre-pressure
in this map always take the newest version and there are examples.
From there you can navigate my complete public map of hotmail.
then you find this spreadsheet to see what the temperature does to the pressure.
http://cid-a526e0eee092e6dc.skydrive.live.com/self.aspx/.Public/pressurecalculationwithtemp.xls
My idea is that when it is colder the tire may get flatter to produce more heat so the tires have more grip and they cool down more because of the lower outside temperature. Tire-surface needs a sertain temperature to have the best grip.


#15

Jadatis:
I remember a few months back CapriRacer had concerns with your tire pressure recommendation tables. The two of you went off and tried to resolve your differences. Apparently he’s still quite concerned with the recommendations you’re making.

Given CapriRacer’s background with years of designing and manufacturing tires, I’d like to see his concerns addressed before taking your recommendations seriously.


#16

Thanks joe,

I STILL have reservations about Peter’s methodology.

Peter, may I suggest you stop posting this on US based web sites, until you’ve successfully addressed the issue of why your spreadsheet gives lower inflation pressures than the vehicle manufacturer posts on the vehicle tire placard.


#17

Is the tire shop guy, who dropped out of high school in his junior year, better educated about what that vehicle needs than the engineers at Honda? I don’t think so. They have test driven those models thousands of miles before they sell them.


#18

Anyone who watches NASCAR races knows that vehicle handling can be adjusted by adjusting tire pressures. There are minimum pressures that the tire and vehicle manufacturers will accept, based on load factors for a given tire size and design and the particular loads likely to be seen at each individual wheel position on a given vehicle, but fuel economy, braking, handling, NVH, tire wear, pot-hole protection and other factors are considered when setting the recommended tire pressures as being greater than the acceptable minimum pressures. In the end, it really comes down to a corporate choice as to the character of the vehicle. When the vehicle owner chooses different pressures, he is personalizing the vehicle to meet his own tastes, although he rarely has means to verify all the ramifications of his decision.


#19

I think Honda seems to know what they are doing, and I would go with 26 psi.


#20

Just remember that Honda had to choose one pressure recommendation to fit all the drivers of that vehicle. It may not fit them all well. Good thing they didn’t have to choose one seat position for everyone.