I left mine at the factory 41 psi.

 

I left it at 41 for the first tank of gas. Then I noticed the rear tires were not wearing evenly across the entire tread width. I dropped the preasure down to 33 per the b-pillar. It did not adversely affect my fuel milage on the second tank and I did not notice any difference in handling.

I am still working on my third tank so I can't report on it yet.

 

I left it at 41 for the first tank of gas. Then I noticed the rear tires were not wearing evenly across the entire tread width. I dropped the pressure down to 33 per the b-pillar... .

I did the same, but interestingly, I don't see such lowered pressure reflected on my console screen. Tires still show 39lbs each (had shown 41lbs), rather than the 33 I set them to. That was 100+ miles ago. What gives?

Now I don't intent to use the TPMS as a substitute for a good tire pressure gauge, but I'm now wondering if the sensors are even giving a ballpark reading. And if not, what good are they?

 

The reason the factory sets the Cherokee's tires around 40 pounds is to cushion and protect the Cherokee during shipment. The dealer is "supposed" to adjust the tire pressure during pre delivery adjustment and inspection but most just give the Cherokee a once over visual inspection. I think the Cherokee's tire pressure monitoring system leaves something to be desired. I have an analog dial tire pressure gauge that I have used for many years. It has never failed me. There is about a 5 pound difference between it and the Cherokee's monitoring system. On a whim I bought a $75 Moroso Digital Racing tire pressure gauge. While it is much closer there is still about a 2 pound difference between it and the Cherokee's monitoring system. I am a real nut about tire pressure. I live along US23/I75 and I have seen far too many deadly accidents due to tire pressure or uncared for tires. While performance is far more important to me than the mpg many of you are concerned about, proper tire pressure effects both. Michigan is just starting to have snowy and icy roads and I don't want my tires rock hard causing them to have less traction.

 

Debunking a Mileage Myth: Can You Really "Pump Up" Your Fuel Economy?

http://www.popularmechanics.com/cars/news/4199963

"We’ve heard folks claim mileage gains by running their tire pressure above the manufacturer’s recommendations. In theory, that makes sense: With more inflation pressure, the tire bulges in the center of the tread and creates a smaller, skinnier contact patch with the road. This should mean less rolling resistance and increased mileage.

What’s more, we know under-inflated tires have a negative effect on fuel economy. The U.S. Department of Energy says that for every 1-psi drop in pressure, you can expect your gas mileage to lower by 0.4 percent.
If under-inflated tires drop your fuel economy, then over-inflated tires must give that mileage a boost—right?

We decided to find out. So, after saying goodbye to half our test car fleet, we took our long-term Honda Fit on an 800-mile road trip from Los Angeles to Phoenix and back again—setting our cruise control to 70 mph except for dips down to 65 mph in central Phoenix and downtown L.A.

The door placard on the Honda recommends 32 psi in all four tires. The sidewall says the maximum pressure for the tires is 50 psi. So for the trip to Arizona, we inflated the tires to 45 psi. We figured 5 psi under that maximum inflation pressure would reduce drag enough to boost our mileage by some measurable amount. Before reaching Phoenix’s West Valley, we were able to travel 394.1 miles, then filled up in Glendale with 9.34 gallons and recorded 42.19 mpg. That’s the best mileage we’ve recorded so far in this car.

Two days later, we dropped the pressure back down to the recommended 32 psi and pointed the Fit’s nose home toward L.A. This time, over the exact same route, at the same speeds, the Fit went 411.3 miles. At the Chevron station in Santa Monica, our Fit drank 9.76 gallons, translating into 42.14 mpg—nearly the exact same mileage.

To invoke the MythBusters, we’d now consider the myth of increased fuel economy from over-inflated tires officially busted. So why didn’t the harder tires with less drag result in better mileage? Well, you’ve got to figure that, at 70 mph or so, the aerodynamic drag of the car’s body is probably outweighing the small improvements the tires gave us.

And we wouldn’t recommend anyone try this one at home either. The vehicle’s handling is compromised when the tires are over-inflated. At 45 psi, the ride was brittle. In fact, the tires were so stiff they nearly vibrated our garage-door opener right off the sun visor. Ouch."

Uneven tire wear will have you buying tires soon as well!

 

I think what happens is they over inflate the tire when installing them on the rim to give it a good seal.
However they should be adjusted down by the pre delivery inspection guys.

This happened to me a couple of weeks ago I had my winter tires installed on my vehicle and they over inflated to get a good seal but forgot to reduce the pressure afterwards.
It sure made for a hard ride as they were around 43 psi instead of the 36 psi.
Geoff

 

I think what happens is they over inflate the tire when installing them on the rim to give it a good seal.
However they should be adjusted down by the pre delivery inspection guys.

This happened to me a couple of weeks ago I had my winter tires installed on my vehicle and they over inflated to get a good seal but forgot to reduce the pressure afterwards.
It sure made for a hard ride as they were around 43 psi instead of the 36 psi.
Geoff

exactly, tires are inflated OVER the recommended cold tire pressure in order to ensure that the tire seats well into the wheel. The presssure, if not reduced by the dealer, should be decreased by the owner, but only ever adjust under cold. (just driving around generates friction, which will increase tire temperature)

 

So with all these posts, what do you think the A/T's on the TH pressure should be set to?

33, 35, 40?

When I picked it up from the dealer they were at 42/43. Some cold weather as set in here and the display is now reading 39/40.

 

For daily driving most "experts" recommend what is on the door jam. When I used to race cars I would tinker with pressures for better handling. But, for daily driving I keep it at the recommended pressures.

 

whatever is marked on the car's b pillar is what you should set them at

 

Good call.

Since the weather gets so cold up there I would recommend checking pressures often. The pressure can drop 1-2 degrees per every 10 degrees if temperature drop.

 

Well, thanks to this thread, I just went out and adjusted all of my tires down from 41 to 36. It is nice having the car actually tell you what pressure the tires are at for a change. My previous cars just told me if it was low or not and then they would not update again until I drove the vehicle for a few blocks after making an adjustment.

 

I recommend a tire gauge over TPMS sensors.

For street only get the Accutire MS-4021B ($7)
For off-road get something with a bleed like the Moroso 89560 ($43 + cover $7)

My tires ranged around 45psi when I received my TH. Was out in the lot deflating the tires getting quizzical looks. Tires are one of the most important features of your vehicle. Just changing from no-season to winter or inflating/deflating your tires will change how your vehicle will handle various terrain immensely.

 

I use the tire pressure monitor to see if I have a flat or slow leak otherwise I check with a tire pressure guage. I like to see the close tire pressure on the screen instead of the warning light. What tire is giving the message when you only get a light? Cannot tell on my Grand Caravan.

 

Totally agree with getting & using a tire gage - always have one in my glove box.

 

Well, I have a gauge built into my Black and Decker air pump. Probably still not as good as a real tire gauge, but seems to be close enough.


Update, ordered the Accutire one mentioned above after looking through all the ones on Amazon. Can't beat the price, and seems to be reviewed pretty well (aside from the idiots that one starred it because it only read 28.5 no matter what they did because they didn't realize there was a sticker over the display that read 28.5). My faith in humanity continues to deflate.

 

Also remember that over inflation will produce more wear and tear on your suspension and steering components. I usually inflate the tires about 1-2 lbs over the recommended pressure. And I only do that because of the temperature variants. It's better to be just a bit over inflated than under inflated.

 

tpms is more accurate than a manual gauge. remember with chrysler system the dash reading wont change til you dive a few blocks.

 

Well, no it isn't and that's the point of the whole post. If you read again, I stated that since the change of pressure from 40+ lbs to 33 lbs, there has been several day's time and 100+ miles covered. Console shows 39lbs per tire, not anywhere near 33. 33lbs was achieve after extensive bleeding down of each tire, so this is not a $2 gauge phenomenum.

 

The pressures listed on the door sill label are the optimum tire pressures for that specific car model for best handling and ride under typical conditions with the listed tire size. The absolute best pressure may vary a few psi due to the actual load. The max pressure molded into the sidewall is the tire safe working limit and has nothing to do the actual vehicle it's on; it could conceivably be that high if that tire was on a relatively heavy vehicle, but that would be a rare occurrence.

 

Mine came delivered at 41psi.
I'll run mine at +2psi over the door of listing of 33 psi during the winter to allow for the loss during the cold.
Summer I'll run them at 33 or 34 unless I'm towing then I'll bump them up +3 or more, depending on weight.
What I find interesting is that those Continentals on the limited are sidewall rated max at 62 psi? That is a huge spread between recommended and absolute maximum.
Must be strong tires!

 

Mine were set at 48 psi when I picked up my Limited. Had the dealer lower them to 35 psi.

 

Well...kinda hard to glean that info from your posts. No, my tpms is right on the money.

 

Then simply ask for elaboration.

 

Why so mad. I offered you some help on the info as posted, no need to get your panties in a wad.

 

I guess I'm one of the lucky ones, my TPMS matches my manual tire gauge almost exactly.

 

The recommended tire pressure for 2014 Jeep Cherokee Limited is 33 PSI for the main tires and 60PSI for the spare tire. Tires and tire pressure is one of the most important factor in ride and handling. 33 PSI should be the ideal pressure for better all year traction in all the conditions and for smooth ride (tires well absorb the pot holes at this pressure). Ideally, the tire pressure should be 33 PSI in all the conditions irrespective of the climate which is not possible. You could use Nitrogen instead of air in tires as nitrogen is less susceptible to pressure changes with temperature change. I believe anything between 33 and 41 is good enough for good traction and handling as winter temperatures can range between -15 and 35 on any given day and the tire pressure drops by 1 PSI for every 10 degree fall in temperature.

 

Mine came from the factory at 41 PSI - If you look at the sidewall on the Continental tires it says max capacity 51 PSI.

 

From 40 years experience on motorcycles the most important equipment on a vehicle are the tires. Especially on a motorcycle where bad equipment could mean disaster. In my case a very important equipment is a accurate tire gauge. Whenever I drive my MC I check in the morning the pressure when tires are cool/cold. When my TH V6 was delivered, the first check I did the following morning were the tires. According to the TPMS pressure ranged between 41 to 43 PSI. My LongAcre racing gauge more or less confirmed these numbers. Reduced pressure to 33 PSI and after driving a few miles the TPMS confirmed the factory recommended PSI. I rely on the TPMS now, however I check the tire pressure weekly with my gauge.

 

Yep. You should run what's listed on the door unless you're on sand or something off road. Doesn't matter what they came at from the factory.

Never heard of a rider driving a motorcycle.

Sent from my Nexus 7 using Tapatalk

 

Clew is correct.

 

My TH tires came dealer-filled with nitrogen. "Cold" (about 65 -- LA in the middle of its current pitiful excuse for winter) the TPMS reads ~29-30 but gradually warms to 33. After reading these posts I'm wondering if I should get them topped up.

 

Suggested tire pressure is always cold. If the door says 33 psi, it should be 33 psi when cold, not after a few minutes of driving. Don't you remember the whole Ford Exploder fiasco?

 

Thanks -- I'm gonna check 'em manually first, then do what I need.