ECO Hubs Who needs 3:07 gears?

[Ronmar]

Yea the manual-auto lockup programming might help, you hold it down into 2nd, or even use it in 1st gear for a little more effective hill decent mode. Just need a reliable way to release it before you take the engine below idle RPM…

 

[GeneralDisorder]

Must be a difference with the older controllers. I don't experience exhaust brake issues at all. There's actually a really steep grade near my house that is between me a groceries many times. Coming down that hill I might have to use the brakes for a couple seconds once to bring the speeds down to where I want it then the exhaust brake and trans gear keep it from accelerating.

I'll have to pay closer attention to what speed it disengages at as I'm slowing down.

If you are talking about crawling speeds only then using the brakes isn't causing that much wear at those speeds so it doesn't overly concern me.

 

[Ronmar]

I think it was lost chain who put up a video showing it hold lockup/ex brake down into second gear. where it drops out in 2nd will probably be a factor of how fast you are decelerating. I shot a crappy video of my scan tool looking at the F/lockup solenoid and mine currently drops out right with the shift to 2nd, but I don’t have any weight on yet, so it slows pretty fast when I roll off the throttle even without the ex brake…

 

[aw113sgte]

Fuel economy update (with eco hubs)
2007 A1R m1096 with 20ft shipping container.
30,400 lbs
Speed 60-65mph
Stock ECM map
5.82 mpg

 

[GeneralDisorder]

Fuel economy update (with eco hubs)
2007 A1R m1096 with 20ft shipping container.
30,400 lbs
Speed 60-65mph
Stock ECM map
5.82 mpg

Try 50-55 instead. You're junk is big and heavy. Congrats on your sizeable gear

Tire pressure? I run the M1088 settings so 81 psi.

Guessing at that weight the best it will get under ideal conditions is probably around 8 or just under. 7.8 to 8.2 would be believable for that combo if all the stars align. But without the hubs you would probably be even lower than your most recent calculations.

From my experience it does seem that the MTV takes a hit of 1-2 MPG or so from the extra axle gear out back. The 4x4 trucks do the best with some guys reporting 11-12. I myself was around 10.2 but I should update that test. It's been a while.

 

[Ronmar]

Yea thats a lotta weight… have you taken individual axle weights? Balance too far outta wack will really show tire wear running a single CTIS pressure across all 3 axles…

”Your junk is big and heavy” Waaaay TMI…

 

[aw113sgte]

Try 50-55 instead. You're junk is big and heavy. Congrats on your sizeable gear

Tire pressure? I run the M1088 settings so 81 psi.

Guessing at that weight the best it will get under ideal conditions is probably around 8 or just under. 7.8 to 8.2 would be believable for that combo if all the stars align. But without the hubs you would probably be even lower than your most recent calculations.

From my experience it does seem that the MTV takes a hit of 1-2 MPG or so from the extra axle gear out back. The 4x4 trucks do the best with some guys reporting 11-12. I myself was around 10.2 but I should update that test. It's been a while.

But I don't want to go slower! I don't really care about the mpg (too much). Running in the 80s psi, I forget the exact value (I think I copied the 1088 values). It cruises nicely at 60-65, well 70-75 too but I "feel" like going that speed may be getting into the unsafe category. We aren't in a rush anyways.

Of note, that mid axle is always about 15f warmer than the front and rear diffs. I assume some extra energy put into that torque divider. May be where some of that mpg go.

 

[aw113sgte]

Yea thats a lotta weight… have you taken individual axle weights? Balance too far outta wack will really show tire wear running a single CTIS pressure across all 3 axles…

”Your junk is big and heavy” Waaaay TMI…

Junk is big and heavy....if only, my wife says otherwise.

Nope I haven't. Best info I have is the little tire whiskers on the new tires, they all wore off very evenly. When going low pressure all the tires bulge out the same - best as I can eyeball.