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  #16  
Old 03-21-2012, 06:00 AM
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Originally Posted by 1WildPig
Went on down to 55 in the rear and the very edges still show "clean"...so, gonna ease on down to 52 and drop the front down to 62 ... this should keep me in the 60 - 64 cold range for front and 50 - 54 cold range for the rear with ambient temperature fluctuation ... don't know if my conscience will let me, but I may even try it at the factory recommended 55 front and try 50 rear - unloaded, that is ... yep, gonna have to get me some chaulk!

Anybody other than F250_ running 55 or so in their 10 ply E load range tires with good results??
I have to run that in the rears cause my tires wear more in the center if I don't. And I tow a 4500# work trailer every day. If I lose a bit in mpg i'll make it up buying tires less often.
 
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Old 03-21-2012, 07:04 AM
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Originally Posted by guitarpicr
I run 70 in the front - 80 in the rear - While towing -

XXXXXXXXXXX2 Had to have 10 caracters
 
  #18  
Old 03-21-2012, 10:21 AM
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Originally Posted by 1WildPig
"As for ride comfort, the 55 psi pressure gives me a good situation as well. If my 20K miles per year were all highway or city/urban roadways, I might get better mileage at 60-65 on my fronts, but only at the expense of center-tread wear. Regardless, over half of my mileage is on narrow county back roads, half of which are regularly pot-holed and patched because of all the heavy log, chip, lumber, and bark trucks which are transported raw materials to either area lumber mills or paper mills. Given that, a lot of my 55 psi riding "like a big car" setup ends up more like a "log wagon" ride because of the road conditions. However, when I did try 55, 60, and 65 psi in the fronts on my old Revo's, I ended up getting [i]worse[i] mileage (due to higher front elevation and the subsequent loss of aerodynamics by running with the air dam in a higher and less efficient ground clearance position), noticeable increase in center tread wear, and an intolerably rough ride."

F250_ , that is interesting about the aerodynamics ... I wouldn't have thought that a fraction of an inch would have made any measurable difference...

I did, however, go back down from 75 F and 65 R to 70 F and 60 R due to the harsh ride and I had also noted that the rear tires weren't touching on the edges ... may have lowered the front end about a 1/16 inch ... I'll check again to see what the rear looks like next time out - may go on down to 55 R......seems as though the factory recommendation should almost be reversed when not hauling!
My personal opinion is that it won't make one iota of a difference. Sorry Pete.
 
  #19  
Old 03-21-2012, 11:31 AM
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If by "recommendation", you mean the psi specified on the door frame, thats the psi the "slide rule guys" at F* say you need to run IOT safely achieve the specified GVW's posted next to those psi figures.

Those door jam figures have nothing to do with MPGs or tire wear
 
  #20  
Old 03-21-2012, 11:35 AM
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Originally Posted by DieselCamper01
My personal opinion is that it won't make one iota of a difference. Sorry Pete.
Opinions are free for everyone, Jay, so no need to apologize.

Who knows, perhaps the fuel quality was degrading over the duration of those fill-ups and road trips.

Still, though, your opinion doesn't change my experience that is based on lots of highway mileage, fill-ups "to-the-neck", same fuel station every fill-up, same fuel pump every fill-up, vehicle parked on the same side of the fuel pump at every fill-up, and vehicle pointing the same direction every fill-up, and hand calculated mileages.
 
  #21  
Old 03-22-2012, 01:04 AM
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Originally Posted by Jmatthews
I have to run that in the rears cause my tires wear more in the center if I don't. And I tow a 4500# work trailer every day. If I lose a bit in mpg i'll make it up buying tires less often.

So you're saying you run 55 in the rears pulling a 4500# trailer and get even tread wear...this is interesting as I may be pulling about that weight or less on a trip this summer...what pressure do you run in the fronts and what fuel mileage do you generally get ?

Danged if you and F250_ ain't got me wanting to try 55 front and 50 rear (empty)...The smoother ride at "lower" pressures are nice but I just figured that the fronts would wear the edges down quicker at that "low" of pressure as most cars do if run at the "recommended" pressure...

F250_, what fuel mileage do you get running those pressures compared to higher pressures?

Has anyone else compared their fuel mileage at 55 F / 50 R or thereabouts and then at higher pressures?

Still ain't got that chaulk yet ! ...
 
  #22  
Old 03-22-2012, 06:19 AM
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Originally Posted by 1WildPig
Danged if you and F250_ ain't got me wanting to try 55 front and 50 rear (empty)...The smoother ride at "lower" pressures are nice but I just figured that the fronts would wear the edges down quicker at that "low" of pressure as most cars do if run at the "recommended" pressure...
I run the full 80 in the front because the weight of the diesel gave the front tires "saddle bags" at lower pressure. Front alignment/wear, the way I drive, and/or tired shocks chipped away at the edges before regular tire wear did anything to the front tires. 80 in the back gave me flat tire wear, but more of it (a bit of wheel spinning from not going easy on the fun pedal). Bouncy? Yup... but the wife never complains - and that's a good barometer for me. Fuel economy? 19.5 Hwy.

 
  #23  
Old 03-22-2012, 06:39 AM
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[QUOTE=1WildPig;11607286]So you're saying you run 55 in the rears pulling a 4500# trailer and get even tread wear...this is interesting as I may be pulling about that weight or less on a trip this summer...what pressure do you run in the fronts and what fuel mileage do you generally get ?

Danged if you and F250_ ain't got me wanting to try 55 front and 50 rear (empty)...The smoother ride at "lower" pressures are nice but I just figured that the fronts would wear the edges down quicker at that "low" of pressure as most cars do if run at the "recommended" pressure...

F250_, what fuel mileage do you get running those pressures compared to higher pressures?

Has anyone else compared their fuel mileage at 55 F / 50 R or thereabouts and then at higher pressures?



I have had the same truck and the same trailer since 2001. It has taken a lot of tires to figure this works for me. I get 13.5 mpg towing like this, I don't really know if I would get better with more air in the tires, but after spending $1000 for tires it doesn't matter to me. I tried putting more in a few times but had the center wear problem.
 
  #24  
Old 03-22-2012, 02:26 PM
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Originally Posted by Tugly
I run the full 80 in the front because the weight of the diesel gave the front tires "saddle bags" at lower pressure. Front alignment/wear, the way I drive, and/or tired shocks chipped away at the edges before regular tire wear did anything to the front tires. 80 in the back gave me flat tire wear, but more of it (a bit of wheel spinning from not going easy on the fun pedal). Bouncy? Yup... but the wife never complains - and that's a good barometer for me. Fuel economy? 19.5 Hwy.
Yeah, that's the other thing about running "high" pressure is that I've read that it causes more wear on front end components - makes sense that if the tire doesn't absorb the impacts that the front end parts will have to...and if that's the case, then the money saved on fuel will go to parts and alignments while enduring the rougher ride...

Seems to be a trade off of either spend your money on tires and fuel with a smoother ride or parts and alignments with a rougher ride ... I'm looking for the happy middle spot ... BUT, that is excellent fuel mileage you got there! .. Say, do you run any fuel additives??
 
  #25  
Old 03-22-2012, 02:29 PM
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Per Jmatthews: I have had the same truck and the same trailer since 2001. It has taken a lot of tires to figure this works for me. I get 13.5 mpg towing like this, I don't really know if I would get better with more air in the tires, but after spending $1000 for tires it doesn't matter to me. I tried putting more in a few times but had the center wear problem.[/quote]


Nothing like experience to provide the best answer!
 
  #26  
Old 03-22-2012, 03:46 PM
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The differences I saw was roughly 1 mpg between the highest and lowest pressures in the front. At the same time, though, you have to keep in mind that I am running a 2WD truck which had a slight door stop profile at the time because I had not yet installed my 2" front leveling kit. Today, since the front is sitting higher with the leveling kit, I don't know that I would see as much of a difference, and truth be told, I suppose the same would have to be true for a 4WD truck as well. This was also prior to the complete conversion over to ULSD which also cost all of us 1-1.5 mpg.

That being said, I was running around 16-17mpg overall during that time, not towing anything, running about 50:50 highway and county roads, traveling at 75-80 mph on the highway, and I also did not have my bed cover at that time (which has not proven to give me any gains in mileage anyway).

Don't mean to sound so iffy about the numbers, but there are a lot of parameters which influence every individual's mileage, and I don;t want you to get the idea that you should necessarily see the same mileages I saw. For context, right now, with the front leveling kit and driving a little more aggressively, but on the same roads, I tend to get about 14.5-15.0 with the ULSD part of the picture. I can still see 17 on the highway if I don't push it hard.
 
  #27  
Old 03-22-2012, 04:26 PM
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Originally Posted by F250_
The differences I saw was roughly 1 mpg between the highest and lowest pressures in the front. At the same time, though, you have to keep in mind that I am running a 2WD truck which had a slight door stop profile at the time because I had not yet installed my 2" front leveling kit. Today, since the front is sitting higher with the leveling kit, I don't know that I would see as much of a difference, and truth be told, I suppose the same would have to be true for a 4WD truck as well. This was also prior to the complete conversion over to ULSD which also cost all of us 1-1.5 mpg.

That being said, I was running around 16-17mpg overall during that time, not towing anything, running about 50:50 highway and county roads, traveling at 75-80 mph on the highway, and I also did not have my bed cover at that time (which has not proven to give me any gains in mileage anyway).

Don't mean to sound so iffy about the numbers, but there are a lot of parameters which influence every individual's mileage, and I don;t want you to get the idea that you should necessarily see the same mileages I saw. For context, right now, with the front leveling kit and driving a little more aggressively, but on the same roads, I tend to get about 14.5-15.0 with the ULSD part of the picture. I can still see 17 on the highway if I don't push it hard.
Yeah, mines a 2wd 6sp. If i'm not towing and making a looong highway run I can get around 20mpg. But I am always towing since I got my Excursion. I keep track of my mpg on my IPhone app. so it Doesn't really tell me much from tank to tank. That's just my average over the last 3 years or so towing in town with the trailer.
 
  #28  
Old 03-22-2012, 04:43 PM
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Yeah, mine's a 4wd, so a little more weight in the front and a different ride level ... what pressure do you run in your fronts Jmatthews?
 
  #29  
Old 03-24-2012, 05:55 AM
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Originally Posted by 1WildPig
Yeah, that's the other thing about running "high" pressure is that I've read that it causes more wear on front end components - makes sense that if the tire doesn't absorb the impacts that the front end parts will have to...and if that's the case, then the money saved on fuel will go to parts and alignments while enduring the rougher ride...

Seems to be a trade off of either spend your money on tires and fuel with a smoother ride or parts and alignments with a rougher ride ... I'm looking for the happy middle spot ... BUT, that is excellent fuel mileage you got there! .. Say, do you run any fuel additives??
Front end wear? I hadn't factored that in. Good catch!

I use the Redline Oil Diesel Fuel Catalyst. That's not the silver bullet for getting good economy though: Everything is the silver bullet. Studies have shown it's common that a person's driving habits are the explanation for getting up to 30% better fuel economy in a vehicle over another driver in that same vehicle.

I get over 16 city/hwy every day, but cruise control on the highway allows the diesel to do one of the things it does well - drone on.
 
  #30  
Old 03-24-2012, 08:02 AM
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Originally Posted by 1WildPig
Yeah, mine's a 4wd, so a little more weight in the front and a different ride level ... what pressure do you run in your fronts Jmatthews?
I run 55-60 in both front and rear. If I tow our camper I'll bump them up for the trip, but it works with my work trailer well.
 


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