I have a 03 F250 sc 4x4, 5.4 with plow. Tag says tire pressure should be 55 front and 70 rear. Should front be higher with plow on or doesnt it matter.

 

i usually have 70-75 in the front and 75-80 in the back with the plow on and 55 front 70 rear normally. i usually have 600-900lbs of ballast behind the back wheels because thats where Western said to put it. Some people say to put it over the axle but i havnt had any problems yet.


2000 F-350 reg cab 5.4L, auto, snow plow package, 8' western pro plow

 

When I had the Load Range E Steeltexs on my truck, I went with the full 80 psi in all 4 tires when I was running the plow. That is where you get your highest load capacity. I had somewhere between 500 and 1000 # in the bed plus the plow on the front, so I thought I needed to go the full 80 psi. Other than that I played around with the psi and could only tell a difference in the ride when it got down to 50psi. I didn't like the steering response at that pressure so I settled for 65 all around or 65 front/ 80 rear if I knew I would be loaded.

big

2000 F250 SD SC 5.4L Gasser
4.10s 4x4 L/S rearend
Western 7'6" plow
White with parchment cloth

 

Welcome Kaufman_sm
We just discussed this topic within the last 2 weeks. It's usually a good idea to do a quick search because often there's been previous disussion that's helpfull. I'll repost what I said last time:

The label on the door jamb is assuming a truck is loaded to the GAWR’s (Gross Axle Weight Rating). If you are operating at a lower weight, you can reduce the pressure for better tire wear, smoother ride and better traction.

Here’s the proper way to determine what pressure to run in your tires. Weigh your truck, getting individual weights for each wheel (or at a minimum each axle). Then consult the tire inflation chart for your brand/model of tire. The chart will tell you what pressure to run based on your weight. If you got individual wheel weights, use the heaviest wheel on an axle to determine what pressure to run on all tires on that axle. If you weigh your truck unloaded you’ll need to do this again with your normal load. If your load fluctuates all the time, it’s probably easier to just keep the tires inflated to handle the highest load you anticipate.

In my case, I carry a 4000 lb slide-in camper occasionally. I keep the truck tires inflated for unloaded driving most of the time. Then before I load the camper, I pump them up for the extra weight. That way the truck rides smoothly with good traction and even tread wear while unloaded. If I was loading and unloading the camper daily or even weekly, I’d probably just keep the tires pumped up. Changing tire pressure daily on a dually would get old real quick.

It's a good idea to read the footnotes and fine print in tire inflation manuals also. For instance, in the Firestone manual it says that if you are driving for long periods at 65 to 74 mph, you should increase the tire pressure 10 psi (provided the wheels are rated to handle the pressure). In the case of the Firestone Steeltex 265/75-16 tire that would be 90 psi if you are at max load. This means that the 80 psi listed on the sidewall is not the max pressure. If you want to drive 75 to 84 mph , you still need those extra 10 psi, but you also need to reduce you max weight capacity by 10%.

You can view a tire inflation table for LT235/85-16 tires at http://www.goodyear.com/truck/pdf/LoadInflLTMetric.pdf .

Here’s the inflation table for the LT265/75R16 Firestone Steeltex tire

Weight Pressure
1910 35
2100 40
2280 45
2470 50
2625 55
2790 60
3000 65
3105 70
3260 75
3415 80

65-74mph add 10psi
75-84mph add 10psi & decrease max load 10%



Harald

2000 F350 4x4 CC DRW V10 4.30ls Lariat LWB.
Firestone Ride-rite airbags, Rancho RS9000 shocks and Torklift Superhitch.
1998 Alpenlite Pendelton 11'10" camper held on by Torklift tie downs.
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Here's the thread https://www.ford-trucks.com/dcforum/DCForumID117/4402.html

I still believe that inflating your tires above 80psi is improper. You'll notice in the chart harald supplied the tires with max. inflation pressures over 80psi were load range F and G.

I haven't had the time to check into this, not to prove harald wrong or myself right, but for my own info. I've never heard harald's explanation about LT tire inflation that he gave in his follow up post before. It is true, the tire is not stamped max. 80psi exactly. I have always been under the impression that the max. load was given at the max. tire inflation as stamped on the tire. If harald is correct then there are probably a lot of people like myself in the dark about it and improperly inflating their tires.

Worth looking into I guess, but I don't know how you'd get a straight answer from your average tire shop.

Waxy

 

Thanks for the replies. I figured if I ran a avg. of 62 psi in front and 70 in rear based on plow and frame weighing 700 lbs I would be good all around for both load and ride.

 

Harald and Waxy, I have followed these tire pressure discussions for some time now, and have concluded that it is very complex. Thus, I propose that Ford would design an automatic tire sensor for all situations based on speed and weight. The tire maker would have to be involved also. Then the truck would automatically fill or deflate all tires to the proper psi regardless of the theories or ignorance of the driver.

 

I'd pay $5 for that, Canadian mind you.

Waxy

 

From reading many discussions on tire pressure in various forums/newsgroups, I can tell you that there's a lot of misinformation and confusion on this topic. I think one of the problems is that people are used to thinking in terms of car tires (size starts with P) that do have a Max pressure. Truck tires (start with LT in size) have a max load, but the pressure listed in not necesarily the max. Here's proof from the Goodyear web site
http://www.goodyear.com/truck/pdf/SelectionDefinitionsLimits.pdf . If you look under inflation limits on that page you can see where higher pressure is required or desireable. If you download the whole manual and go to page L-2, you can see the table that specifically tells you to add 10 psi for higher speed operation. I really didn't make this up I researched all this when trying to make the best of a overloaded condition I had years ago. It's interesting that you can also exceed the max load for slow speed operation! Check out the chart on L-2 if you don't believe me.

Harald

2000 F350 4x4 CC DRW V10 4.30ls Lariat LWB.
Firestone Ride-rite airbags, Rancho RS9000 shocks and Torklift Superhitch.
1998 Alpenlite Pendelton 11'10" camper held on by Torklift tie downs.
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No, really, I do appreciate your factual responses and try to adapt them to my situation. Thanks, again.

 

 

At least Goodyear puts this information on their web site.
If Firestone has tire load/pressure table on the web, I have not yet been able to find it.

I wanted to get the straight story about tire load vs pressure from the people who should know best. So last week I paid a visit to my local Firestone tire dealer.

After explaining that I had just purchased a new Ford F-350 and that it had come from the factory with SteelTex Radial R4S LT265/75R16 BW Load Range E tires, I asked for a table of tire pressure vs tire load for this tire.

And here is the definitive answer that we all have sought:
"Just use the pressure that Ford specifies."
Well, there it is, then. End of discussion. Pretty simple, huh? No need to further beat this topic into the ground.

I can see three possibilities for this answer:
1) This Firestone employee is a) new, b) not too quick, c) busy
2) This information is a Firestone secret and the employee was following SOP by referring me to Ford's inflation info
3) This truly is the best answer that Firestone has for me and my tires.

Let's just say that I felt I wasted a trip to the Firestone store.


2003 F350 Regular Cab XLT 4WD V10 6-Spd 3.73LS
Additions: Access Cover

 

I did the same thing by going to a Firestone dealer. With a little persuasion, I got him to get the book out and I spent some time reading the chart for the Steeltex LT265/75-16 tire and the footnotes. The info is very similar to what Goodyear says. That makes sense because they all go by guidelines from their industry group, the Tire and Rim Association.

I think a lot of these tires guys are like salesmen; they don't have a clue, but want to sound like they know it all.

Harald

2000 F350 4x4 CC DRW V10 4.30ls Lariat LWB.
Firestone Ride-rite airbags, Rancho RS9000 shocks and Torklift Superhitch.
1998 Alpenlite Pendelton 11'10" camper held on by Torklift tie downs.
Remove I_HATE_SPAM_ from email address to email me.

 

I have had my 2002 F350 for a couple of years. I mostly have it to pull my 27 foot 5th wheel camper. The door post shows 80 lbs all around. I recently noticed on the inside of the fuel door a sticker that shows front 50 lbs, rear 80 lbs. The sticker has a number "D35510" My local Ford dealer has no clue about which numbers are correct. I just have kept 80 lbs all around even if it gives a rough ride.

Bosskat

 

I run unloaded except for a camper shell year round. The heaviest thing I pull is a small trailer with an ATV. Front axle weight was 3960 and rear axle was 3040. If I run anything over 45psi. front and 40psi rear I get excessive wear from the center of the tires. I really wish I could find the chart mentioned above for BFG All Terrains! One question I pose is if I switched from an E to a D rated tired would the pressure I've been running change as well?