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Actual, honest, real world MPG from your 6.5

Right or wrong, I dont know.
I just run what is posted on the drivers door frame.
I then watch the tread wear. It most always seems to be about even.
Even though the tires are 285/75 R16 and IIRC rated up to 80 pounds.
 
dbrannon79 said:
running... oversize all-terrain tires
Click to expand...

Unless those A/T tires are absolutely necessary, consider going with H/T for the next set for an instant 10% increase in mileage. I run H/T Load Es on the pickups and used them on the Burb. Never had a bit of trouble with the tires doing their job whether it was through mud at the dump / landfill or pushing through 20" of snow (no plow, just truck).

Tried A/T once and they lasted 4K miles as they tore up my lawn, made the truck ride like it was on a marshmallow, and ate more fuel. No bueno for a mostly highway cruiser.

I do air-down depending on the surface conditions where I have gone as low as 15psi to get out of slick mud on an incline with a full load in the bed. While the tires are lower than normal psi, I moderate the speeds accordingly.

In general, the H/T tires run at max cold rating and have no downsides in terms of handling or tread wear. Actually, I prefer the more firm ride, but that is me. With the dually though, max cold seems like a bit much for the rears and have not settled on an empty pressure yet.
 
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dbrannon79 said:
In all honesty I should have gone with HT tires. this is what I have on the truck now.

Pathfinder AT LT265/75R16 123S E1 OWL

Discount Tire | Tires and Wheels for Sale | Online & In-Person

www.discounttire.com www.discounttire.com
Click to expand...
That looks to be about the same tread as what the tires on My truck has.
I despise that tread, howler growler to the max.
For some reason I was thinking My truck required the 265/75-16 tires but then a while back I checked the PSI rating and seed that it said 245/75-16. To Me that seems a little bit small but guess thats what I will go with when it is time.
I am also going to eliminate these custom aluminum wheels and I’ll be looking for a set of stock steel wheels in the meantime.
 
When taxes come in I desperately need new rear tires. (Dually problems lol) I've always ran a/t tires because.. well.. NY. Icey roads suck.. but I'm thinking maybe I'll buy HT tires this time..see how they hold up.. for some reason I go through tires fast even when properly aligned..I considered buying a extra set just because it would be nice to have them when needed and but not sure on that one yet... The truck will hit the big 300,000k mile mark in about 800 more miles so priority is going to be getting injectiors and manifolds done .. engine still seems strong as hell so want to treat her.
 
dbrannon79 said:
Mine don't howel or at least I can't hear them lol but I think when the time comes HT's will be the way!

@MrMarty51 before going to 245's check your speedo with your phone's GPS. mine actually was correct with the 265's installed.
Click to expand...
Yup, speedo is off about 5%, reads slow. 65 is about 63 on the speedo.
 
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Soft tires becoming the suspension system works the rest of the truck harder.
If suspension is too rough and you dont max payload, consider redoing your springs (probably due after 25 years) and maybe have them go lighter on main springs and use heavy overloads for when you do max out. Max weight should ride rough anyways.

On AT tires- they will always wear out sooner. Softer compound tires for more traction during acceleration especially off pavement. If there is still 10% tire life left- get the new tires before the old ones wear out. Use the hiway tires on road and save the AT for the rough trips. Junkyard rims for the AT are pretty cheap.
 
My 95 1 ton always had 235/85 r16 tires. With the bale deck on (1ton)+ it was rough with the original sacked out leaf springs. I put the heaviest leaf set in I could get. It is about an inch above the over loads, it is my nicest riding vehicle now.

In winter I run singles on the back, 265/75 r16 tires, the same on the front. My OK tire guy said they were the same diameter as the 235/85 tires. These are Toyo tires with a very aggressive tread. Go anywhere you want.

I run about 45-50 psi in the back duals, makes for a nice ride, it will still support the weight.

Front about 65, the same on rear singles
 
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I wish I knew how to get a smoother ride out of mine without loosing height. I've thought about 3/4 ton front coil springs and maybe doing something to the rear leaf springs but I don't want it to get costly! my overloads are right at 1/4" from touching the rest of the leaf pack. when I let all the air out of the air shocks they dam near touch. probably worn out lol but the height seems right though
 
I ran air shocks which made the ride much better. My trouble was with a 2000 lb deck on, if the air leaked out I was on the over rides. It was very rough until I had one or 2 bales on.

The factory leafs are 2750 per side, The other options were 3000 and 3250. They were not as expensive as I thought they would be.
 
Just went out this afternoon after work and took a good gander at my tires and how everything was sitting. All four tires seemed to be slightly squating or have a slight bulge on the sidewall (ground side) and I could press my thumb into the tire slightly. lol my hillbilly way of seeing if the tires are low. haha

Decided to up the tire pressure from 50 to 65, plus when I checked my air shocks, they only had 20lbs in them. filled the shocks to 60 since I have that 500-800lb camper shell on the bed now. I'll do the chalk test hopefully this weekend, but I am curious if the truck will feel like it's rolling easier.

If the weather is warm enough this weekend I may also jack up both ends and check if there is any wheel roll resistance along with checking the rear brake shoe adjustment again. I know the extra pressure in both is gonna make it rough, but just for the curious cats sake it shouldn't hurt anything for the next couple of days.

While I was out there with the tire gauge in my hand my wife tells me "you gonna check mine too" lol good thing I did, her tires were all over the place, surprised her tire warning light wasn't on! had to even them all off!
 
A less common anymore, but good thing to do is do a chalk test when empty, and jot it down. Then get your normal heavy load, and do another chalk test. Write it down.
Guys that run empty most of the time run on the lower setting and air up when they hook up to big trailer or set to do heavy work load for that season.

See, one more reason y’all need hummers or duece and a half! Central Tire Inflation System. Raise and lower air pressure on the fly. A couple guys around here adapted hmmwv portals (geared hubs) to their pickup axles and have the extra low gearing and ctis.

Search around to see if you have a good spring/ suspension shop near you. The one that was here forever, you could just tell him - “I want it 1 inch lower or 2 higher than now, and a softer ride empty and not hit overloads until X weight in bed.” He could look at the springs and tell you if he could re-arch them or if had to be new. Skips Spring Service here incase anyone is around the Vegas area, but I haven’t used them in a decade.
 
I just watched a couple of youtube videos to get a better understanding on the chalk test. now it all makes sense! one of the videos did mention that it can decrease fuel mileage depending on the weight of the rig and type of tire. they also talked about accounting for weight distribution with bumps and turns. I wouldn't be surprised if by the time I get done with the test unloaded, the tire pressure ends up at something like 30 psi like they did in the video even though the tires are rated for 80!

on the rear springs, we have a spring shop in the big city nearby that will do re-arching and can custom build them but they are high priced. I do remember a while back someone at my work had mentioned that I could do a couple of things with the overloads since I am running air shocks. they mentioned something about pulling and flipping the overloads upside down or even pulling them off to have a softer ride as long as I don't plan to do any heavy hauling but for light loads the air shocks would cover for them on short trips.
But I'm not sure doing that would be a very good idea as a cheap fix.

as for the front with a arms and coil springs, I don't think much can be done, although bouncing the front end seems "springy" with stiff shocks lol all around I think a soft shock would be the best bet for a softer ride. shocks were replaced when I did all the front end. I thought I had used AC Delco ones but I just looked at my purchases and see where I bought Gabriel 81668 guardian shocks. not sure if those are rated "heavy duty" but that could be the problem with a stiff ride.
 
MrMarty51 said:
That looks to be about the same tread as what the tires on My truck has.
I despise that tread, howler growler to the max.
For some reason I was thinking My truck required the 265/75-16 tires but then a while back I checked the PSI rating and seed that it said 245/75-16. To Me that seems a little bit small but guess thats what I will go with when it is time.
I am also going to eliminate these custom aluminum wheels and I’ll be looking for a set of stock steel wheels in the meantime.
Click to expand...
LOL I have always been a fan of the 265/75's and the aluminum wheels.

The 265's always corrected my speedometers
 
Remember your truck may originally came with tires for 75 psi, but light wall tires and now the different tires are rated for 90, but because of different way tire is made you might need only 50.
Hmmwv for instance is between 24 and 55 on same exact tire, rim, truck- just all depending on load. Or even terrain- they are rated down to 8psi.
So it’s all circumstance...
 
Yeah, I did notice a bit of difference today going to work. the front is a bit more rigid but steers a little easier. the back, well it almost feels smoother since I added enough air to get the springs off from resting on the overloads. air shocks are at 60 psi and with the camper shell they are up about a 1/4 inch from the overloads. before I thing they were on them.

I think for ride quality I need to look at some softer shocks in the front, then research for the best size highway tire. I wonder if a taller but slightly narrower tire would help kill three stones. softer ride, better mileage and lower rpm for the freeway. only thing is these allterrains are still somewhat new, Ill have to go back through records but they might only have 6-7k miles on them.

Even later on if I ever find a cheap used set of 3.73 gears, that will drop rpm's by about 200, this combined with slightly taller tires maybe drop it by 300 and get some better mileage. I have a complete pumpkin gear set that has posi-lock and pinion already set in the pinion housing but it has 4.10's on it. all I would need to do is swap out the gear and pinion and install. but that is another topic for research. the truck has the famous one wheel wonder spider gears with 4.10's installed.
 
dbrannon79 said:
Yeah, I did notice a bit of difference today going to work. the front is a bit more rigid but steers a little easier. the back, well it almost feels smoother since I added enough air to get the springs off from resting on the overloads. air shocks are at 60 psi and with the camper shell they are up about a 1/4 inch from the overloads. before I thing they were on them.

I think for ride quality I need to look at some softer shocks in the front, then research for the best size highway tire. I wonder if a taller but slightly narrower tire would help kill three stones. softer ride, better mileage and lower rpm for the freeway. only thing is these allterrains are still somewhat new, Ill have to go back through records but they might only have 6-7k miles on them.

Even later on if I ever find a cheap used set of 3.73 gears, that will drop rpm's by about 200, this combined with slightly taller tires maybe drop it by 300 and get some better mileage. I have a complete pumpkin gear set that has posi-lock and pinion already set in the pinion housing but it has 4.10's on it. all I would need to do is swap out the gear and pinion and install. but that is another topic for research. the truck has the famous one wheel wonder spider gears with 4.10's installed.
Click to expand...
I might have a set of 3.73 gears. I am pretty sure I do. It was a kit for the 1994 K3500. I was going to up the gear ratio and use 1st gear.

Make an offer
 
3.73's will drop 60 mph rpm's by about 400 from the 4.10's

Get some 20" rims with the low sidewalls, should help mpg and look cool too, in the "Hood" anyway. :D Oh and a set of air bags for the front with a storage tank and a dump valve. Then you can fit right in :)
 
NVW said:
3.73's will drop 60 mph rpm's by about 400 from the 4.10's

Get some 20" rims with the low sidewalls, should help mpg and look cool too, in the "Hood" anyway. :D Oh and a set of air bags for the front with a storage tank and a dump valve. Then you can fit right in :)
Click to expand...
Here is the calculations I did online. the first screenshot is what I see now at 65 in overdrive and TCC locked. second is with 3.73
The third one is if I can fit a set of 285/75-16 highway tire without needing a lift going from a 265/75-16

1642032446100.png
1642032490214.png
1642032921933.png
 
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