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Discussion Starter #1
I just got my first Excursion 4 days ago and I'm loving it so far. It drives so much better than my ex. cab 250 did. My question is what PSI do you guys run in stock 265 size tires. I was thinking 80 because of fuel milage and the truck weight of 7190 pounds. But I know that my 250 rode a lot better at 65 all the way around. Thanks.
 

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I run mine 55-60 in the front and 70 in the rear. That's what I ran in the stock size tires and what's on it now (285's). I would make sure you have "E" rated tires before you pump a lot of air in them.
 

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I've played a little bit w/ tire pressures and have found on my stock BFG AT KO's that front at 60 and rears at 55 (no load or towing) seems to be the best ride and handling. Didn't notice what engine you have. The PSD is heavier than the V10.

When I start to tow I increase the rear to 65 but leave the front at 60.

It's well within the load limit of the tires (E rated), gives a good contact patch, and does not "wander" but then my tongue weight is light at 1000#. I'd suggest you go to a scale and weight the beast with a full load of fuel and the driver (front and rear) so you have an idea what loads are actually being carried.

The other thing you can do is the "Chaulk test". Run a couple of lines across the tread with chaulk and then move the truck forward until a couple of revolutions of the tire have taken place. Check the Chaulk mark and see if it is evenly "worn".

D
 

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I've played a little bit w/ tire pressures and have found on my stock BFG AT KO's that front at 60 and rears at 55 (no load or towing) seems to be the best ride and handling. Didn't notice what engine you have. The PSD is heavier than the V10.

When I start to tow I increase the rear to 65 but leave the front at 60.

It's well within the load limit of the tires (E rated), gives a good contact patch, and does not "wander" but then my tongue weight is light at 1000#. I'd suggest you go to a scale and weight the beast with a full load of fuel and the driver (front and rear) so you have an idea what loads are actually being carried.

The other thing you can do is the "Chaulk test". Run a couple of lines across the tread with chaulk and then move the truck forward until a couple of revolutions of the tire have taken place. Check the Chaulk mark and see if it is evenly "worn".

D
I do the same when towing also :)
 

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Don't set your pressure according to the load rating. When I had my Procomps installed, I was surprised to find that they only hold 65PSI even tho there E rated. Bottom line, regardless of what you decide to set them at, make sure it's within the range printed on the side of the tire.
 

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Discussion Starter #7
They are Firestone Transforce A/T's load range E. The tire says max load 80 psi and the drivers door says 50 in the front 55 in the rear. Im going on a long trip in a couple of days and I think I'll set them on 55 psi all the way around.
 

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I don't remember the year but at some point Ford changed from Load Range D tires as the reccomendation/OEM for Excursions to Load Range E. When they did that they applied the reccomendation to ALL year Excursions even the ones that came from the Factory w/ Load Range D tires.

I did not see the year of your EX but on my 2002 that is what happended. The door sticker and inside the Fuel Door says Load Range D and the lower pressure 65 psi, but the E's are much higher.
 

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Discussion Starter #9
Mine is an 01 ex. Im not sure what it had from the factory but it had new load range E tires when I got it. I set them to 55 but I dont think 65 would hurt anything. I want the best mpg but I dont want it to ride like a tank.
 

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Since the E Range tire sidewalls are so much stiffer than D's, I keep mine at the "lighter" end of the pressure and pretty much never go over 65 psi (even when towing).

The chaulk test will tell you if the are under inflated at 65.

D
 

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65 psi here. Except for the one with the slow leak. It can get down to 35 before it begins to show any sign of being low. But I keep a close eye on it.
 

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They are Firestone Transforce A/T's load range E. The tire says max load 80 psi and the drivers door says 50 in the front 55 in the rear. Im going on a long trip in a couple of days and I think I'll set them on 55 psi all the way around.
I threw the exact tires on my ex the day I got it. (82k miles on it at that time) I played with air pressures till I found just the right setting. I go 5lbs above what ford recommends. (60/55 i think?) I just remember it being 5lbs more. I air up the rear when hauling 10 lbs more.

I rotate every other oil change (would have been 6k miles back then) but now that I switched to synthetics with a bypass filter, I rotate every oil change (7500 miles)

I am now about to turn 160k, and still have even and perfect wear. I probably can get away with another 10-20k on em down here in Florida. I still have a bit of room before the wear bars. :thumb:
 

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That's the best way to set your tire pressure, if you have access to a dirt road even quicker way, go from the asphalt to dirt about 50 feet or so and look at your tire, I'm not talking soft dirt or sand a solid dirt road, if you have a fresh dirt print crawling up your sidewalk and you know the ground didn't break under you it's not enough air, if you get a strip down the middle but doesn't make it all the way to the tread shoulder you have to much air.
I run mine at 65-70 all the time with stock rims on Michelin 265/70-16 E rated
Let me also note that also depends on the width of your rim and width of your tire, if you have a 6" wide rim and a 12" wide tire obviously there is going to be a problem with getting proper tread wear
 

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Discussion Starter #14
55 psi sucked it felt like rolling on marshmellows. I tried 70 psi on the way home from the beach. That slammed us every little bump. I will probably try 65 next.
 

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I think 65 is the magic number for stock setup, I run at 65 psi no issues and even tread wear, only go to 70 in the rear with a heavy trailer maybe 75 but that's a huge load
 

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Discussion Starter #16
I ended up putting them at 60 tonight. They felt good on the way home but we will see when I go back to the beach this weekend.
 

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Might want to try and stagger the pressure 5lbs. Little minor change, but it helps. (I know ford recommends 50/55. but don't remember which is which.) I run 55/60, I'd have to run out and check which. (I run nitro, so my garage set it for me) I think it's front/rear. So I'd try 60/65 since you like the 65 setting.
 

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I like the 60 psi figure an just finsihed 400 miles of towing w/ my (roughly) 1000 lb tongue load. It makes for a decent ride with the "E" rated tires in the rear since I'm still not loaded heavy and we only have 2 passengers up front. I have the WD hitch set to bring the truck down evenly across fornt and rear.

I only go higher when I relly load the TT up w/ stuff and/or the rear of the EX.

D
 
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