315/75/16 Tyre (Tire) Pressure

[Chook]

I finally got a set of 35" Tyres (pick them up tomorrow). Just wondering what pressure you all run with these on highway & off road ????

 

[Paladine71]

Because of my truck's weight, I run 40lbs road and 18 lbs off-road.

 

[08H3]

50 on / 15 off. So many of the answers to that question are preference and opinion though.

 

[reaper]

...I run 40lbs road and 18 lbs off-road.

:yeahthat

 

[backcountryislife]

45 on road, and off road I run fronts at 16-18, rears at 12-15.

 

[H32NV]

God your guy's teeth much chatter on the highway. I run 34psi on highway and 12-18 offroad depending(not scared to go below 18 because I have the beadlocks). At 40psi with my Duratracs, the ride was really rough. They were Load Range E, which plays a part of this equation. I am now on Load Range D Goodyear mTR's, and I run them comfortably at 34. I have a bit of accessories too, so the vehicle weight is up there. I see no gas mileage improvement between 34-40psi, and 34 gives the best ride and corners well. You shouldnt need to run 50 psi on wide tires because the footprint is larger. Following the equation P= F/A, and re-arranging the symbols, P*A = F. For the same lift force F on the truck, an increase in A leads to a decrease in P, to end up with the same F. Unless we are running on a formula one circuit and really concerned about sidewall stiffness for cornering on pavement, then we should be running at the same or LESS pressure than we used to on our 265's. My duratracs wore perfectly all 65,000 miles at 34psi on road. I'm sticking with that.

 

[08H3]

My tire guy is one of the few people that I will pretty much take at their word. He's been in business for more years than I have been alive and is very well respected. As a GENERAL rule, he says inflate them to the max PSI listed on the sidewall for best wear and mileage. So far, the advice seems to be pretty much dead on. Ride quality really is no different at 40psi or 50 psi and I pick up about .25mpg. I know that's not much but it does add up over thousands of miles. Like I said before though, I really don't know how much any one person can back their "theory". Probably only the guys in lab coats at Goodyear have any real science to backup their claims.

 

[06 H3]

I am around 32-35 PSI. I find it interesting you guys run your PSI that high. I was on a jeep forum and they seem to run 27-32. I wonder why they are much lower then what we run.

 

[reaper]

I actually leave mine at 18 a lot of times.... driving home from the trail at 18 isn't all that bad.

 

[Neo]

38 for soft ride 45 for best fuel and 16 off road Toyo MT's here

 

[Blacksky]

Hey Chook,
What brand and tread pattern did you get?
I'm due for a new set and want to upgrade to 35's but having trouble finding any in Darwin.

 

[Chook]

Thanks everyone.......... I replaced my OEMs with Mickey Thompson ATZ 5 rib 265/75/16 and got great mileage. This time I am going to Mickey Thompson ATZ in a 315/75/16 and a 4 rib design (I still do a lot of highway miles but If I didn't I would go with BFG KM2)

Rule of thumb I was given with the 265/75/16 was try it @ 40 PSI and if it is too harsh drop it back only as much until it is comfortable. When I first started I had them around 38psi but over time I ended up @ 40 psi as the tread wore down. Did 100,000 Km (60,000 Mile) on this set and there is still plenty left.

Wasn't sure what pressure to run the 35" @ but like H32NV mentioned above the physics formula suggest I run lower pressures.

With a lot of you folk running higher than that I might keep it @ 40psi for a while and fiddle up & down from there. (18 Offroad is what I used previously also with Sand driving @ 14)

Cheers,
Chook

 

[Chook]

Hey Chook,
What brand and tread pattern did you get?
I'm due for a new set and want to upgrade to 35's but having trouble finding any in Darwin.

Hey Blacksky.......... I was warned that the reason all the H3 came with 265/75/16 is because it is the only tyre likely to be in stock. This guy said he had to wait a week to get 35's by air courier when he was in the NT. I did some searching and Mickey Thompson dealers are in the NT (see link) so thought they should be able to get them (if not there are plenty on Ebay just pay the shipping)

http://www.mickeythompsontires.com....alerPostcode=800&dealerSuburb=&dealerState=nt

Cheers,
Chook

 

[Chook]

My tire guy is one of the few people that I will pretty much take at their word. He's been in business for more years than I have been alive and is very well respected. As a GENERAL rule, he says inflate them to the max PSI listed on the sidewall for best wear and mileage. So far, the advice seems to be pretty much dead on. Ride quality really is no different at 40psi or 50 psi and I pick up about .25mpg. I know that's not much but it does add up over thousands of miles. Like I said before though, I really don't know how much any one person can back their "theory". Probably only the guys in lab coats at Goodyear have any real science to backup their claims.

Hey 08 ............ I would be reluctant to go to the Max as the tire will gain at least 4psi as it heats up in use. Not doubting your advice but cold should be at least 5 PSI less than the Max pressure on the sidewall to allow for this.

 

[Steve #1]

My tire guy is one of the few people that I will pretty much take at their word. He's been in business for more years than I have been alive and is very well respected. As a GENERAL rule, he says inflate them to the max PSI listed on the sidewall for best wear and mileage. So far, the advice seems to be pretty much dead on. Ride quality really is no different at 40psi or 50 psi and I pick up about .25mpg. I know that's not much but it does add up over thousands of miles. Like I said before though, I really don't know how much any one person can back their "theory". Probably only the guys in lab coats at Goodyear have any real science to backup their claims.

You don't think it would be in your tire guy's best interest to get the center of your tires to ware out quickly?

The rule of thumb I go by is to draw a chalk line across the tread, drive around the block and see if it wares off even. If the line is lighter in the center, let some air out. Lighter on the outside, put some more air in. Once you get that worked out, if you want better mileage, add a little air. Want a softer ride, let a little out.

 

[cbetts]

I was in the habit of running 35 PSI on all my cars for the road but I noticed weird wear marks on my 35" KM2s on the outer lugs. I bumped them up to 40 PSI and the wear marks went away. I take them down to 15 PSI off road due to the thick sidewalls.

 

[08H3]

You don't think it would be in your tire guy's best interest to get the center of your tires to ware out quickly?

Of course it would if he was a total douche that wanted to only make a sale, but we've been good friends and mutual customers for years.

 

[08H3]

Hey 08 ............ I would be reluctant to go to the Max as the tire will gain at least 4psi as it heats up in use. Not doubting your advice but cold should be at least 5 PSI less than the Max pressure on the sidewall to allow for this.

Sidewall tire pressures are ALWAYS listed as cold inflation pressure.

 

[Flash]

I run 45psi on road and 15-18psi offroad.

 

[skeptic]

With my Duratracs I run 40psi on road when I remember, then drop down to ~32-34 on the trail for the much softer ride - which is where they still are now after the last offroad trip. After a day or two I forget the low tire light is even on.

 

[skippy]

Chook I am the same as others and run 45psi on road and have the stauns set at 18psi

we should catch up for lunch soon!

 

[Chook]

Chook I am the same as others and run 45psi on road and have the stauns set at 18psi

we should catch up for lunch soon!

Ok great........I am going to try my usual 40 psi & 18 psi and see how that goes for now. With the tyres now fitted I am off to Gordon Country tomorrow to blood these newbies. I noticed the fronts rub on the mudflap @ 3/4 lock.

I am travelling a fair bit with work but would be great to catch up for lunch sometime.

 

[08SolarFlareH3]

I run 40 psi in mine.

I can't believe someone else hasn't asked yet, were are the pics Chook :wink:

 

[Chook]

Ok.......... The new shoes got their feet dirty today. Took a trip to Condamine River Road. (The Condamine River is 2hrs South West of Brisbane & is one of the tributaries to Australia's longest river Murray)

 

[Chook]

Ok.......... The new shoes got their feet dirty today. Took a trip to Condamine River Road. (The Condamine River is 2hrs South West of Brisbane & is one of the tributaries to Australia's longest river Murray)

Here is a Wiki Link to the Condamine River if you are interested. Minor error on my part........Condamine a tributary to the Darling River but the Darling meets the Murray near Mildura (so it ends up in the Murray)

http://en.wikipedia.org/wiki/Condamine_River