Sponsored

OK, Tire Gurus Tell Me....

Gladman

Well-Known Member
First Name
Alistair
Joined
Oct 25, 2020
Threads
4
Messages
398
Reaction score
295
Location
Alberta
Vehicle(s)
2021 Gladiator Overland High Altitude Diesel
Occupation
Retired
I am asking if my logic with tire inflation is beneficial or not recommended practice.
Quite a bit of my driving (60-70%) is with the vehicle unloaded and just me driving.
The tire pressure decal on the door frame lists max tire pressure fully loaded.
So, for example, the max pressure is 44 psi front and rear.
Considering thatI am only 25% loaded for max capacity I reduce the tire pressure 10% to 39 psi for my normal unloaded driving, and then increase to max when I know Iā€™ll be driving at or near max with passengers or supplies.

Is this consistent with maximizing tire life and running tires safely?

Thanks
Sponsored

 

RodRecket

Well-Known Member
Joined
Sep 13, 2019
Threads
27
Messages
989
Reaction score
1,235
Location
Minnesota
Vehicle(s)
2021 AEV JT370
chalk method is simple and effective. rub chalk across a section of tire and then roll it forward. If the pattern looks even there you are properly inflated. If it only shows chalk in the middle you are over inflated. The inverse, underinflated.

Do this with the tires mounted on the vehicle.

The size of tire, wheels, what you carry in your truck, the options it has all has an effect of what pressure is right.
 

ShadowsPapa

Well-Known Member
First Name
Bill
Joined
Oct 12, 2019
Threads
178
Messages
29,083
Reaction score
34,568
Location
Runnells, Iowa
Vehicle(s)
'22 JTO, '23 JLU, '82 SX4, '73 P. Cardin Javelin
Occupation
Retired auto mechanic, frmr gov't ntwrk security admin
Vehicle Showcase
3
I am asking if my logic with tire inflation is beneficial or not recommended practice.
Quite a bit of my driving (60-70%) is with the vehicle unloaded and just me driving.
The tire pressure decal on the door frame lists max tire pressure fully loaded.
So, for example, the max pressure is 44 psi front and rear.
Considering thatI am only 25% loaded for max capacity I reduce the tire pressure 10% to 39 psi for my normal unloaded driving, and then increase to max when I know Iā€™ll be driving at or near max with passengers or supplies.

Is this consistent with maximizing tire life and running tires safely?

Thanks
Why not check with the TIRE MAKERS? They have inflation charts that show how much pressure for given loads.

I'd trust the tire maker over what almost anyone else would give.
The chalk test works - mostly. Tire sidewall stiffness also comes into play.
 
OP
OP

Gladman

Well-Known Member
First Name
Alistair
Joined
Oct 25, 2020
Threads
4
Messages
398
Reaction score
295
Location
Alberta
Vehicle(s)
2021 Gladiator Overland High Altitude Diesel
Occupation
Retired
Why not check with the TIRE MAKERS? They have inflation charts that show how much pressure for given loads.

I'd trust the tire maker over what almost anyone else would give.
The chalk test works - mostly. Tire sidewall stiffness also comes into play.
Yes I can do that. However just sitting around online in the evening and knowing there is a great knowledge base here I thought I would ask the question and tap into that. Iā€™ll start with the chalk test though.
Thanks guys.
 

Renegade

Well-Known Member
First Name
Zac
Joined
Sep 11, 2017
Threads
38
Messages
3,562
Reaction score
4,693
Location
Signal Mountain, TN
Vehicle(s)
2020 JT
Build Thread
Link
I am asking if my logic with tire inflation is beneficial or not recommended practice.
Quite a bit of my driving (60-70%) is with the vehicle unloaded and just me driving.
The tire pressure decal on the door frame lists max tire pressure fully loaded.
So, for example, the max pressure is 44 psi front and rear.
Considering thatI am only 25% loaded for max capacity I reduce the tire pressure 10% to 39 psi for my normal unloaded driving, and then increase to max when I know Iā€™ll be driving at or near max with passengers or supplies.

Is this consistent with maximizing tire life and running tires safely?

Thanks
I thought they all recommended 37 psi on the door jamb...
 

Sponsored

OP
OP

Gladman

Well-Known Member
First Name
Alistair
Joined
Oct 25, 2020
Threads
4
Messages
398
Reaction score
295
Location
Alberta
Vehicle(s)
2021 Gladiator Overland High Altitude Diesel
Occupation
Retired
That could very well be, I was just using an example from a GC. I assumed the principle would be applicable to any vehicle.
 

ShadowsPapa

Well-Known Member
First Name
Bill
Joined
Oct 12, 2019
Threads
178
Messages
29,083
Reaction score
34,568
Location
Runnells, Iowa
Vehicle(s)
'22 JTO, '23 JLU, '82 SX4, '73 P. Cardin Javelin
Occupation
Retired auto mechanic, frmr gov't ntwrk security admin
Vehicle Showcase
3
I thought they all recommended 37 psi on the door jamb...
No.
Mine says 38, others will vary based on tire and "trim".
I run 36-37 in the A/T tires I'm running now because the foot print is bigger. More meat on the road, less PSI needed to support the same truck weight. These tires are a couple inches wider so the square inches on the road is more, less PSI needed to hold the truck up.
If I put skinnier or smaller tires on than the stock tires it came with, I'd run higher psi.
 

Renegade

Well-Known Member
First Name
Zac
Joined
Sep 11, 2017
Threads
38
Messages
3,562
Reaction score
4,693
Location
Signal Mountain, TN
Vehicle(s)
2020 JT
Build Thread
Link
No.
Mine says 38, others will vary based on tire and "trim".
I run 36-37 in the A/T tires I'm running now because the foot print is bigger. More meat on the road, less PSI needed to support the same truck weight. These tires are a couple inches wider so the square inches on the road is more, less PSI needed to hold the truck up.
If I put skinnier or smaller tires on than the stock tires it came with, I'd run higher psi.
Ok, but the OP specifically said 44 psi on the door jamb. This seems off in comparison to standard. Maybe the diesel gets a higher spec? Or, maybe he doesnā€™t have his Gladiator yet and hasnā€™t seen the door jamb?
OP- Is this just a hypothetical question? If so, sure, you can run less pressure when unloaded.
 

Renegade

Well-Known Member
First Name
Zac
Joined
Sep 11, 2017
Threads
38
Messages
3,562
Reaction score
4,693
Location
Signal Mountain, TN
Vehicle(s)
2020 JT
Build Thread
Link
I go with what's recommended from the tire manufacturers usually 5 PSI under max if it's unloaded I only adjust it after that depending on the terrain. Spend a lot of time off road and during the winter a lot of time on the highway. The chalk method works great for determining an optimal pressure... If you want to be quick about it go 5 to 10 PSI under the max on the sidewall. Awaiting the 17,000 other responses based on opinion...
The sidewall means nothing for your particular vehicle. Itā€™s a maximum pressure, which is for meeting that particular tireā€™s maximum weight rating. Thereā€™s my ā€œopinionā€.
 
OP
OP

Gladman

Well-Known Member
First Name
Alistair
Joined
Oct 25, 2020
Threads
4
Messages
398
Reaction score
295
Location
Alberta
Vehicle(s)
2021 Gladiator Overland High Altitude Diesel
Occupation
Retired
Yes it is a general question that could be applied to any vehicle.
I have run 6 vehicles this way but have not run out a set of tires in 20 years due to low mileage.
My JT will be delivered to the dealer tomorrow so I donā€˜t know the specific rating on the Overland high altitude diesel. I know it has 20ā€ tires, same as the GC.
 

Sponsored

OP
OP

Gladman

Well-Known Member
First Name
Alistair
Joined
Oct 25, 2020
Threads
4
Messages
398
Reaction score
295
Location
Alberta
Vehicle(s)
2021 Gladiator Overland High Altitude Diesel
Occupation
Retired
5psi under max? lol

max inflation on my tires is 65; thatā€™d mean 60. Nope.

The psi listed on the door jamb is what the factory tires should be filled to.
Note that I said 10% under, or in the case of 44 psi, 5 psi less.
 
OP
OP

Gladman

Well-Known Member
First Name
Alistair
Joined
Oct 25, 2020
Threads
4
Messages
398
Reaction score
295
Location
Alberta
Vehicle(s)
2021 Gladiator Overland High Altitude Diesel
Occupation
Retired
Also, my understanding is the door jamb max is also max load.
 

CerOf

Well-Known Member
Joined
Jan 1, 2021
Threads
18
Messages
1,377
Reaction score
1,611
Location
Dallas
Vehicle(s)
ā€˜21 JTRD
Also, my understanding is the door jamb max is also max load.
Door jamb is the cold inflation amount for stock tire.

If youā€™re towing or hauling a heavy load, youā€™ll likely want more.

in a sports car/sedan, youā€™ll want more if driving aggressively.

remember the Ford Explorer? It listed something like 28psi in the door placard. This led to increased heat, tread separation, and roll overs.

it was mentioned above to consult the tire manufacturerā€™s load to inflation chart. Thatā€™s a great idea!
With experience you will know what psi you can do when unloaded.
My current tires are ā€œeā€ rated. I would feel comfortable running them at 34~35 unloaded. But do your own research on the specs for your tires and vehicle.
 
OP
OP

Gladman

Well-Known Member
First Name
Alistair
Joined
Oct 25, 2020
Threads
4
Messages
398
Reaction score
295
Location
Alberta
Vehicle(s)
2021 Gladiator Overland High Altitude Diesel
Occupation
Retired
Door jamb is the cold inflation amount for stock tire.

If youā€™re towing or hauling a heavy load, youā€™ll likely want more.

in a sports car/sedan, youā€™ll want more if driving aggressively.

remember the Ford Explorer? It listed something like 28psi in the door placard. This led to increased heat, tread separation, and roll overs.

it was mentioned above to consult the tire manufacturerā€™s load to inflation chart. Thatā€™s a great idea!
With experience you will know what psi you can do when unloaded.
My current tires are ā€œeā€ rated. I would feel comfortable running them at 34~35 unloaded. But do your own research on the specs for your tires and vehicle.
You are saying put more psi than max at max load? That doesnā€™t seem correct to me.
Sponsored

 
 



Top