43psi recommended in 325/60-18 Terra Grapplers - Nissan Titan Forum
Titan Wheels, Tires & Brakes Technical discussion about the wheels, tires, brakes, etc.

Reply
 
LinkBack Thread Tools Rate Thread Display Modes
#1 (permalink) Old 08-21-2009, 01:45 PM
Registered User
 
Pops's Avatar
 
Join Date: Apr 2007
Location: Okc
Posts: 8,844
Thanks: 2,260
Thanked 2,937 Times in 1,785 Posts
iTrader Score: 1 reviews
43psi recommended in 325/60-18 Terra Grapplers

.... 43 psi appears to be the official recommendation from Nitto.

I know it's been asked several times on the forum and now we have an official answer from the manufacturer. A discussion about LT tire psi and load handling in another thread prompted me to give Nitto a call to see what PSI I'm officially supposed to be running to retain the original tire load capacity.

Terra Grappler LT325/60-18 are rated at 50psi MAX allowed.

After some calculations, the lady at Nitto told me that I should be running them at 43psi under all circumstances.

2005 Armada LE 4x4
Pops is offline  
The Following 3 Users Say Thank You to Pops For This Useful Post:
bills1974 (08-21-2009), dc_909 (08-22-2009), layer1 (08-21-2009)
Sponsored Links
Advertisement
 
#2 (permalink) Old 08-21-2009, 01:48 PM
Premium User
Nissan Titan Status - Premium Member
 
Walrus's Avatar
 
Join Date: May 2006
Location: Fort Walrus, USA
Posts: 113,819
Thanks: 17,143
Thanked 21,631 Times in 12,917 Posts
iTrader Score: 18 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

And that sounds right to me.

I run the stock Rugged Trails at 40 and bump to 44 for towing the car hauler.


BaldWhore
Starfishwhore

Red meat is not bad for you.
Fuzzy green meat is bad for you.

You know you had a great night last night when you make it home the next day missing at least half your clothes.

It's not the zombies you have to watch out for. It's the stupid people.
Walrus is offline  
#3 (permalink) Old 08-21-2009, 02:34 PM
Registered User
 
yamatitan's Avatar
 
Join Date: Sep 2007
Location: Baton Rouge, Louisiana
Posts: 2,990
Thanks: 89
Thanked 314 Times in 260 Posts
iTrader Score: 0 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

Thats what I run my toyos at.


2006 CC LE, BT, OFFROAD with nav and sunroof
Procomp 6" ($1300.00),SAW coilovers ($1000.00),Rear Sway-away piggybacks ($399.00),PRG Offroad Traction Bars ($489.00), C-30 Deaver pack ($140.00), PRG Shackles ($139.00), PRG UCA ($599.00), NCD 2" SPACER ($89).
18" Procomp 8179 wheels ($700.00)
37x13.5x18 Toyo MT's ($1900.00)
Banks Monster Exhaust ($500.00)
2* Timing Advance ($0)
Huskyliner floorliners ($140.00)
Volant Powercore ($320.00)
Tech12volt box with 2xkicker 12 and kicker amp ($340.00)
Color Matched Bushwacker Pocket style flares ($600.00)
Go Dominator type II steps ($320.00)
Warn 12k powerplant with milemarker winch mount ($1865.00)
Stillen Big Brake Kit ($905.00)
Money wasted so far=$11745.00
yamatitan is offline  
#4 (permalink) Old 08-21-2009, 03:00 PM
Registered User
 
themaildude's Avatar
 
Join Date: Dec 2005
Location: Deltona, Florida
Posts: 1,449
Thanks: 168
Thanked 326 Times in 164 Posts
iTrader Score: 4 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

Would the 325/65/18's be the same?



IRC CREW MEMBER

Click Here For My Mods
themaildude is offline  
#5 (permalink) Old 08-21-2009, 03:16 PM
Registered User
 
Pops's Avatar
 
Join Date: Apr 2007
Location: Okc
Posts: 8,844
Thanks: 2,260
Thanked 2,937 Times in 1,785 Posts
iTrader Score: 1 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

Quote:
Originally Posted by themaildude View Post
Would the 325/65/18's be the same?
Yes. I went ahead and asked because my next set will be 35's and there's plenty of people on this site with them. She asked if I know if it's the same max psi since I had the specs in front of me and I told her "yes" and she said "yes, it's the same then".

2005 Armada LE 4x4
Pops is offline  
#6 (permalink) Old 08-21-2009, 03:20 PM
Registered User
 
themaildude's Avatar
 
Join Date: Dec 2005
Location: Deltona, Florida
Posts: 1,449
Thanks: 168
Thanked 326 Times in 164 Posts
iTrader Score: 4 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

Thanks Pops. Gotta add some air. I've been running 36lbs on this set. I ran 40 on my 325/60/18's and got 52K out of them and could of got some more. They wore really well @ 40 psi.



IRC CREW MEMBER

Click Here For My Mods
themaildude is offline  
#7 (permalink) Old 08-21-2009, 05:08 PM
Premium User
Nissan Titan Status - Premium Member
 
layer1's Avatar
 
Join Date: Jul 2008
Location: Winchester, VA
Posts: 10,777
Thanks: 1,597
Thanked 1,677 Times in 1,213 Posts
Garage
iTrader Score: 9 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

Good to know there Pop, much appreciated.
I'm already at 40psi, might have to bump them up to 43psi this weekend.



08.5 SE CC, 4x4, Smoke
My Garage
Link to my Mod's
layer1 is offline  
#8 (permalink) Old 08-21-2009, 05:35 PM
Premium User
Nissan Titan Status - Premium Member
 
bills1974's Avatar
 
Join Date: Sep 2007
Location: Delray Beach, FL
Posts: 36,474
Thanks: 10,508
Thanked 9,199 Times in 5,693 Posts
iTrader Score: 7 reviews
Send a message via AIM to bills1974
Re: 43psi recommended in 325/60-18 Terra Grapplers

I run mine between 43 and 45, so I guessed right

2014 Jeep Wrangler Unlimited

Cowl Done With Bedliner
Radiator Bypassed - Transmission Fluid
Wife's Ride: 2014 Infiniti Q50 S
My Other Ride: 2007 Sea Doo Speedster 200


AKA: Crossdresser Whore™
The Bald Avenger®

"It's really bad when I have to go into the fridge to count how many beers I had last night because I lost track."
"Why is the rum always gone?"

bills1974 is offline  
#9 (permalink) Old 08-21-2009, 07:49 PM
Registered User
 
loufish's Avatar
 
Join Date: Oct 2004
Location: Sunny Burbank, CA
Posts: 6,375
Thanks: 78
Thanked 678 Times in 480 Posts
iTrader Score: 11 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

got a little double-posting going on...

I'll re-post here...

How can you run the same pressure fully loaded AND un-loaded?

The Titan can't weigh enough for the tiires max rated 50 psi, but just as you don't need a full 50 psi, you would reduce tire pressure when you reduce the weight it's carrying...I'm not saying it's 100% linear, but as you remove weight, there can be a safe reduction in air pressure...

Titan KC SE 2wd StreetFighter...(Step away from the Titan)
PRG Performance Kit w/SAW's
including rear SAW 2.25" Piggys
Rear Bumpy-Bumps
35" General Red Letter Grabbers on Pro Comp 1028 Wana-be Bead lock wheels
3.73 Gears and TruTrac for Gription
Born 9/2004
I replaced the factory air in my tires with a Citrus scented air package...
Oh yeh....I replaced the screw that holds on the mirror with a trick black oxide one that nobody will see or care about...


2002 Honda XR650R
loufish is offline  
The Following User Says Thank You to loufish For This Useful Post:
NorCal 4x4 (08-21-2009)
#10 (permalink) Old 08-21-2009, 08:35 PM
Registered User
 
Pops's Avatar
 
Join Date: Apr 2007
Location: Okc
Posts: 8,844
Thanks: 2,260
Thanked 2,937 Times in 1,785 Posts
iTrader Score: 1 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

Lou, if it's not raining, I'm gonna pick up the TT in the morning and take it to the scales to prove to myself then post on ClubArmada how Weight Distribution affects axle weights. I'll write a list of the process down tonight and I'll add checking the PSI while hitched to my to do list.


When I was early at truck driving, I was asking an experienced diesel mechanic about sliding the fifth wheel and a trailer's tandem axle for weight distribution. The discussion strayed to discussing retreads then PSI. To put it simply, he said the only way to increase PSI is to add air and the only way to reduce it is to remove air. He said it's the volume of air inside the tire that determines the PSI. I asked about a tire squatting. He said, yea it's squatting flatter on the bottom but it's also bowing out wider somewhere else so the total volume is still the same. Bottom line, unless there is air being added into the tire or the total allowable volume space that it can occupy is being reduced, the total PSI remains constant regardless of the weight set on top. The only thing that changes with a changed shape are the areas where the stress on the container (tire) are relaxed while others are increased. If 43-psi is the pressure required to hold the tire in its rigid shape then the PSI will not change.

So, what about a blowout from overloading?? If you have a P-rated tire for example that's aired to 35-psi then overloaded so the sidewalls are about to burst and put a pressure guage to the tire, the total PSI will still be at 35-psi. The difference is the pressure points where the flattened tread area has been relaxed which requires another area to take over the load (like the sidewalls) and the weakest area is the most flexible so as the pressure pushing against the tread is reduced, the pressure on the sidewall is increased, BUT the total PSI is still at 35-psi. If a tire is rated for 2,000-lbs and 43-psi is documented as enough pressure required to keep the tires shape enough to prevent pressure redistribution then that scenerio will not happen until the max load is exceeded.

I hope my babbling makes some sense.

2005 Armada LE 4x4

Last edited by Pops; 08-21-2009 at 08:38 PM.
Pops is offline  
#11 (permalink) Old 08-21-2009, 09:05 PM
Registered User
 
NorCal 4x4's Avatar
 
Join Date: Aug 2004
Location: Sierra Nevada foothills - CA
Posts: 6,185
Thanks: 1,028
Thanked 964 Times in 810 Posts
iTrader Score: 4 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

All the lady from Nitto did was look at the maximum load the stock P265/70R18 tires can handle, (at their maximum 35 psi), and match the load capacity via psi on the LT325/60R18 D. However, she forgot to de-rated the OEM tires' 2601 lbs. capacity to 2365 lbs. because they are being used on a truck instead of a car. [Divide by 1.1].
So to match the OEM tires' maximum capacity, the LT325/60R18 D needs only 36 lbs.

But as Loufish said, it is dependent on load, not matching the OEM's tire's maximum capacity. However, you also don't want to run the LT's below 35 psi unless you're off roading. For this tire, 36 or 35 isn't a big difference, but for many sizes of LT's the range will be more like 50-35 psi, that can be selected for loading on a Titan, while the same tire could be used up to 80 psi for some models, on bigger trucks.

Quote:
Originally Posted by walleeme View Post
And that sounds right to me.

I run the stock Rugged Trails at 40 and bump to 44 for towing the car hauler.
The P285/70R17 Rugged Trail is rated for a maximum 35 psi. You must not exceed 35 psi, and if one were to blow while airing up ... not good for the face.

Most things are engineered for a 10% buffer, so you might be safe at 39 or 40 psi, but at 44 psi you're exceeding spec by 25%.

Last edited by NorCal 4x4; 08-21-2009 at 09:18 PM.
NorCal 4x4 is offline  
#12 (permalink) Old 08-21-2009, 09:54 PM
Registered User
 
loufish's Avatar
 
Join Date: Oct 2004
Location: Sunny Burbank, CA
Posts: 6,375
Thanks: 78
Thanked 678 Times in 480 Posts
iTrader Score: 11 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

Quote:
When I was early at truck driving, I was asking an experienced diesel mechanic about sliding the fifth wheel and a trailer's tandem axle for weight distribution. The discussion strayed to discussing retreads then PSI. To put it simply, he said the only way to increase PSI is to add air and the only way to reduce it is to remove air. He said it's the volume of air inside the tire that determines the PSI. I asked about a tire squatting. He said, yea it's squatting flatter on the bottom but it's also bowing out wider somewhere else so the total volume is still the same. Bottom line, unless there is air being added into the tire or the total allowable volume space that it can occupy is being reduced, the total PSI remains constant regardless of the weight set on top. The only thing that changes with a changed shape are the areas where the stress on the container (tire) are relaxed while others are increased. If 43-psi is the pressure required to hold the tire in its rigid shape then the PSI will not change.

So, what about a blowout from overloading?? If you have a P-rated tire for example that's aired to 35-psi then overloaded so the sidewalls are about to burst and put a pressure guage to the tire, the total PSI will still be at 35-psi. The difference is the pressure points where the flattened tread area has been relaxed which requires another area to take over the load (like the sidewalls) and the weakest area is the most flexible so as the pressure pushing against the tread is reduced, the pressure on the sidewall is increased, BUT the total PSI is still at 35-psi. If a tire is rated for 2,000-lbs and 43-psi is documented as enough pressure required to keep the tires shape enough to prevent pressure redistribution then that scenerio will not happen until the max load is exceeded.
Think about it, if the tire is rated for max load of 3000 lbs at 50 psi, 50 psi isn't needed when the tire is only loaded to say 1250 lbs. I'm not advicating running the tire down at 25 psi, I'm just saying a tire with that much load rating can be run safely at less pressure with less load.

I've run 33-35 inch LT tires all my life on the rear of empty p/u trucks at 35 psi and never had a wear problem, or tread seperation. Of course when loading up the trucks I'll run more pressure.

Titan KC SE 2wd StreetFighter...(Step away from the Titan)
PRG Performance Kit w/SAW's
including rear SAW 2.25" Piggys
Rear Bumpy-Bumps
35" General Red Letter Grabbers on Pro Comp 1028 Wana-be Bead lock wheels
3.73 Gears and TruTrac for Gription
Born 9/2004
I replaced the factory air in my tires with a Citrus scented air package...
Oh yeh....I replaced the screw that holds on the mirror with a trick black oxide one that nobody will see or care about...


2002 Honda XR650R
loufish is offline  
#13 (permalink) Old 08-21-2009, 10:06 PM
Registered User
 
RyBo's Avatar
 
Join Date: Jan 2008
Location: Laguna Niguel, CA
Posts: 2,132
Thanks: 361
Thanked 394 Times in 216 Posts
iTrader Score: 23 reviews
Send a message via AIM to RyBo
Re: 43psi recommended in 325/60-18 Terra Grapplers

Holy sh!t I run mine anywhere between 32-36 psi lol...40 would cause mine to bounce like no other on the freeway...wonder what I should run them for being a 325/50R22?


"No offense Titantalk, but I'd rather be on a beach..."
RyBo is offline  
#14 (permalink) Old 08-22-2009, 05:46 AM
Registered User
 
loufish's Avatar
 
Join Date: Oct 2004
Location: Sunny Burbank, CA
Posts: 6,375
Thanks: 78
Thanked 678 Times in 480 Posts
iTrader Score: 11 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

Quote:
Holy sh!t I run mine anywhere between 32-36 psi lol...40 would cause mine to bounce like no other on the freeway...wonder what I should run them for being a 325/50R22?
I just installed a set of Pro Comp Extreme A/T's in 35-12.50/ 17....Dropped pressure from 40 to 35 and made a big difference in ride...

Titan KC SE 2wd StreetFighter...(Step away from the Titan)
PRG Performance Kit w/SAW's
including rear SAW 2.25" Piggys
Rear Bumpy-Bumps
35" General Red Letter Grabbers on Pro Comp 1028 Wana-be Bead lock wheels
3.73 Gears and TruTrac for Gription
Born 9/2004
I replaced the factory air in my tires with a Citrus scented air package...
Oh yeh....I replaced the screw that holds on the mirror with a trick black oxide one that nobody will see or care about...


2002 Honda XR650R
loufish is offline  
#15 (permalink) Old 08-22-2009, 08:25 AM
Supporting Vendor
 
Discount Tire's Avatar
 
Join Date: Apr 2008
Posts: 1,085
Thanks: 225
Thanked 185 Times in 144 Posts
iTrader Score: 1 reviews
Re: 43psi recommended in 325/60-18 Terra Grapplers

According to Goodyear, the stock tire (265/70-18 114 SL SR-A) @ 35psi carries 2601lbs. The 325/60-18 119 D2 (50 PSI MAX cold) Nitto Terra Grappler @ 35 PSI carries 22405lbs and @ 40 PSI carries 2605lbs. If one were to air this size Terra Grappler up to 45 PSI, the tire will carry 2780lbs. At max pressure (50 PSI cold), the tire will carry 3000lbs.

Low Prices! More Choices! FREE Shipping!
At The Store: www.discounttire.com
To Your Door: www.discounttiredirect.com

Sales and Technical: 1.888.459.4080

Found a Lower Delivered Price?

Useful Links:
Tire Size Calculator
Current Promotions
Interactive Wheel System
Wheels & Tires 101

Last edited by Discount Tire; 08-24-2009 at 11:21 AM.
Discount Tire is offline  
Reply

Jump to top


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes Rate This Thread
Linear Mode Linear Mode
Rate This Thread:



  Similar Threads
Thread Thread Starter Forum Replies Last Post
nitto terra grapplers 325/65/18 titan922 Buy/Sell 24 02-03-2009 12:52 AM
325 60 18 Terra Grapplers KIT-SS Buy/Sell 6 09-03-2008 07:47 AM
Eagle 026 and 325/60 18 terra grapplers trophybass Buy/Sell 5 03-29-2007 03:40 PM
Nitto Terra Grapplers 325/60/18 Footloose301 Titan Wheels, Tires & Brakes 6 11-22-2006 05:19 AM
325/60 18 Terra Grapplers mnmsmith Titan Wheels, Tires & Brakes 26 06-26-2006 10:14 AM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On