tire pressure

[nightvision]

Hi all,
I just got some new tires install on my Nissan Frontier v6. The Max PSI on the tire is 35 PSA. The door said to pump it to 27. I told the tire installer that I was using the truck to pull a boat so he said he will pump the front tires to 27 PSi and the back tires to 35 PSI.

This is procedure correct? What do you think?

Thanks.

 

[BrianS.]

Re: tire pressure

I think the back tires will heat up and exceed Max PSI of 35.

 

[tommays]

Re: tire pressure


it depends on the tire some will wear real bad in the center if there over inflated


The pressure on the door has to due with the load on the tire as well as a comprise on ride comfort

I have the biggest tires you can get on a Silverado there max is 44 cold and they wear very even at 40 PSI and still give a good ride

If i do the same think to my wifes equniox it will losen your teeth

Tommays

 

[Silvertip]

Re: tire pressure

Disagree. Maximum inflation pressure prevents heat build up, not add to it. You should check the owners manual carefully to determine at what tire pressure the maximum load rating is for the truck. I'll bet there are two ratings. I'm surprised that there is an 8# differential. That said, just because the tire says "MAX inflation pressure 35# does not mean the tire MUST be inflated to that pressure. That's simply the inflation pressure required to carry the maximum load for that tire. 27# is obviously specified for ride purposes but that's over 20% under the max inflation pressure so when heavily loaded I'd say you risk tire overload. In your case I doubt 35 PSI is required but I'd certainly run at least 30 PSI. It all depends on the size of the boat however.

 

[SS MAYFLOAT]

Re: tire pressure

Load is a tricky word in this case. Pulling the heavy load is different than hauling the load. When hauling the load with higher air pressure, the load will keep the tread of the tire flat to the pavement. Without the load and high air pressure, the tread is likely to only leave the center section of the tread in contact with the pavement resulting in faster tire wear. (and less traction as well)

In your case of pulling the boat, How much tongue weight do you have? What percentage of the capacity of the vehicle does that amount to? Then adjust the air pressure to that percentage over the normal inflation. To my knowledge, the tongue weight should be 10 to 15% of the total weight of the boat/trailer. However, if the calculation is over the recommended tire pressure, a different tire maybe needed with heavier spec limits.

I run my tires 10% under the max for best mileage.

As for heat build up, the tire will get hotter at lower inflation due to the side walls flexing beyond their safe operating specs. Gotta keep in mind that all the load is transmitted to the tread through the sidewalls. Without the higher air pressure to hold them up it makes the sidewalls work harder. With the sidewalls being thinner and fewer plys, it doesn't take long for the sidewalls to fail. This is not good while pulling/hauling a load.

 

[Bob_VT]

Re: tire pressure

I run nitrogen in my tires. Search the net and you will see that there is less heat build up and constant pressure.

 

[SS MAYFLOAT]

Re: tire pressure

Hi Bob, Yeah, nitrogen is great. It won't expand and contract with weather changes and altitude as well. Guess that is why it is used in aircraft tires.

 

[bandit86]

Re: tire pressure

just go with 27psi. your truck may not be heavy enough to need 35psi at all.

 

[ZmOz]

Re: tire pressure

I think the back tires will heat up and exceed Max PSI of 35.

This is already taken into account when the manufacturer determines that 35 is the max...that's why they specify COLD PSI.

As for nitrogen, that is nothing but a marketing gimmick. Yes your tires expand as you drive, the manufacturer knows this and takes it into account when determining the recommended tire pressure. This expansion is not a problem. They use nitrogen in race cars and air planes because their tires are used in VERY extreme circumstances that your tires will never see. Furthermore, oxygen molecules leak through the rubber in your tires faster than nitrogen. Air is already about 80% nitrogen, which means after you top off your tires a few times you have more like 90-95% nitrogen. That little bit of other gasses will make no difference on your passenger vehicle.

 

[Drrockter]

Re: tire pressure

I was suprised when I got new tires for my Wrangler that the inflation was 50 p.s.i. My wifes SUV tops at 32. :/