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.

 

[Gunny 0369]

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.

 

[Gunny 0369]

Ok, almost 6,000 miles running echo hubs with original gears, 3126 engine with a 330 hp program. Note: I weigh 27,800 lbs
Oh and I had previously driven over 25,000 miles with the 3:07/ high speed gears and NO echo hubs.
Update…..
Love the noise reduction
Love knowing everything is spinning half the RPM’s

Hate that the exhaust braking only slows me down to 20 mph before they disengage. They were effective down to less than 10 mph before. Which means I’m using the brakes way way way more. Also while going down hill, I mean down mountains with single track dirt forest roads I have to manually shift the transmission into 1st gear to keep from riding the brakes constantly to maintain a nice controllable speed.
Also while going down 10% grade mountain roads on paved roads the exhaust brakes don’t keep me in a safe speed like they did before with the echo hubs.

FUEL Mileage everyone wants to know.
With 3:07/high speed gears I got over 25,000 miles averaging 6.5
With original gears and echo hubs I’m getting about 8-8.5 mpg. Not what I hoped for but it is what it is. It’s better! Also my max speed is 60 mph. I personally aim for 50-55 mph in 6th gear which is the optimal mpg while monitoring the instant MPG according to the ECM. I’m able to live monitor it. Oh and forget ever using 7th gear….got to 80mph and it still never shifted to 7th gear.

Hate that it starts from a stop in 2nd gear. Makes for a sluggish start.

Which brings me to my big question? Any possible way to reprogram the transmission to use 1st gear in all situations? Different ECU from a different vehicle? Just spit balling….

Thanks Keith for the real world testing, good info.
missed u in the midwest!