Load Range E PSI??

[FirstTimeTruckOwner]

Hey guys!

Just put a set of Nitto Terra Grappler G3s on the truck in LT275/70/18. Unfortunately they only came in SL or E load range and I opted for E.

I don't do any towing, so it's probably overkill, but I'm wondering if it's ok to run them at a lower PSI for a better ride? I had them at 38 and when they warmed up on the highway they got up to around 41-42 and the ride was considerably rougher.

Right now I have them around 35 and the ride is better, but can they be run lower?

 

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[TravisJr]

Not exactly a direct comparison, but a data point for reference:

I’m on 37/13.50/22 Nitto Ridge Grapplers, which are 12-ply (load range F). They are definitely stiff. I run them at 35 front and 30 rear when not towing, and have had no issues. This is not my daily driver though, so I can’t speak to how that may affect wear over time.

Depending on how low you want to go, you may need to reset your TPMS values to avoid getting low pressure messages.

 

[TX_Critter]

You can, try doing a chalk test to find the correct pressure for even wear. Basically you color in with chalk in a strip across the tread and drive a few revolutions on a smooth surface, you want to see the chalk rubbed off evenly all the way across. If more rubbed off on the shoulders and left the middle fully colored then you are under-inflated, if vice-versa then you are over inflated.

 

[Pingbling23]

50 cold in my e rated ridge grapplers and they ride good.

 

[FirstTimeTruckOwner]

50 cold in my e rated ridge grapplers and they ride good.

Dang that seems so high!! You feel like it rides smoother at 50 than it does at 38?

 

[FirstTimeTruckOwner]

Not exactly a direct comparison, but a data point for reference:

I’m on 37/13.50/22 Nitto Ridge Grapplers, which are 12-ply (load range F). They are definitely stiff. I run them at 35 front and 30 rear when not towing, and have had no issues. This is not my daily driver though, so I can’t speak to how that may affect wear over time.

Depending on how low you want to go, you may need to reset your TPMS values to avoid getting low pressure messages.

I can tell they are definitely stiffer than the stock Goodyear Territory MTs that came with the truck. I'll have to do the chalk test and see what it shows. Running a lower PSI in the back makes sense though.

 

[FirstTimeTruckOwner]

You can, try doing a chalk test to find the correct pressure for even wear. Basically you color in with chalk in a strip across the tread and drive a few revolutions on a smooth surface, you want to see the chalk rubbed off evenly all the way across. If more rubbed off on the shoulders and left the middle fully colored then you are under-inflated, if vice-versa then you are over inflated.

I'll have to go borrow some of my kid's sidewalk chalk and do this. Right now all four tires are at 35 psi...I'm curious what the chalk test would show at that psi.

 

[Pingbling23]

Dang that seems so high!! You feel like it rides smoother at 50 than it does at 38?

Tire shop put 45 in when they installed. I felt like they were riding a little soft and went to 50 myself and I think it rides good.

 

[2SHOES]

I run 285/70R17's Load Range E BFG AT KO3's at 45 PSI for all road driving, and then drop to 20 PSI when I'm offroad. 45 psi is the correct pressure for the weight of my truck for the correct chalk test for my truck setup. I wouldn't run them too low, you'll end up wearing down the tire crazy fast.

 

[hdrolling]

Mine are 20" not 18" but I do 50 in the front and 45 in the back, I also have Bilstein shocks. Seems to ride fine but coming from 1 ton duallys this 1500 is a Cadillac.

 

[Sport0519]

I just put on a set of Bridgestone Dueler At Ascent in 275/70r18 load range E. Right at 45 psi cold ended up being the sweet spot for me.

 

[FirstTimeTruckOwner]

I'll have to air up my tires to 45 then and see what happens. I do a TON of highway driving (75-80mph) and want to ensure a smooth ride. In hindsight, I probably shouldn't have gone with E rated tires, but for this specific tire and size, my options were E or SL...

 

[Sport0519]

I'll have to air up my tires to 45 then and see what happens. I do a TON of highway driving (75-80mph) and want to ensure a smooth ride. In hindsight, I probably shouldn't have gone with E rated tires, but for this specific tire and size, my options were E or SL...

You can definitely tell a difference going from the load range C to a load range E tire, but I don't think the ride is terrible. I contemplated purchasing the General Grabber ATX 275/70r18 in SL but decided against it since I do tow a trailer. Finding tires larger than the factory 275/65r18 in anything but a load range E is a challenge...

 

[FirstTimeTruckOwner]

You can definitely tell a difference going from the load range C to a load range E tire, but I don't think the ride is terrible. I contemplated purchasing the General Grabber ATX 275/70r18 in SL but decided against it since I do tow a trailer. Finding tires larger than the factory 275/65r18 in anything but a load range E is a challenge...

I don't tow (and don't plan to), but I guess never say never. I also don't haul anything in the truck bed outside of a few tailgate chairs lol.

But can't hurt anything to air it up, drive it around, and see what happens.

 

[TreyK42]

2023 1500 AT4X - Toyo Open Country R/T Trails 285/75r18's. E-rated. I run them at 34 PSI cold. Once I get them warmed up they run between 36-38 PSI.

Ride is never going to be the same as an SL or C rated tire, but these run well at a lower pressure. Just hit 42,000 miles on them and wear is very consistent although they sure are getting noisier.

I'm thinking I'll get another 5k-7k miles out of them until I switch over to the R/T Pros.

From my perspective the lower the pressure the better for normal/daily use and air them up higher whenever you plan to tow heavy or carry a heavy load in the bed.