Fuel Mileage - Automatic vs. Manual

Running the mid west. Ohio Alabama Illinois. I just took 44,979 lb Ohio to Texas. It drop my average down to 8.3 over the pass 11,500. Usually I do Ohio to South Carolina but not with this new truck yet. That's got big pulls going back North so that probably drop it some.

I heard if you need a new clutch in the DT-12 it like $4,000. Because it more then just a clutch. It will give warning if you getting the clutch to hot. I found that out in my other truck when sliding trailer tandems.

It also has Downhill Mode. You lock in the speed you want to downhill and it will hold the gear for you and run the Jake brakes. Lots of people drive them like regular transmission and they complain how it keeps shifting gear downhill or they say it's will not hold the gear and roll in neutral and say they are not safe.

 

There's a reality TV show in the making here!
We get a brand new glider of some kind and install a 1693 Cat and 5X4 or 6X4 tranny in it, along with the shift pattern decal on the sun visor or dash, then put out an add for a driver.

"Driver wanted, brand new truck, top wages, company benefits, 85 cpm, paid layovers, hotels and meals, mountain driving experience preferred but not a necessity, flexible home time, apply in person at blah blah blah address."

How many drivers do you think would show up, and how many do you think might get the truck started and make it out of the parking lot?

 

The automated manual transmissions, AMTs, are not prone to problems. The older Eaton Ultrashifts are clunky because you have an Eaton computer talking to an OEM computer and they don’t speak the same language. The new Eaton Endurant does not have that problem. The iShift and DT12 have an advantage being an integrated power train product. An AMT does not improve fuel mileage vs a good driver. It gets better fuel mileage through integration and down speeding.

 

Ive got a 2017 Volvo D13 with iShift... Gets 7.6 mpg average since I started driving it (80k miles ago), running from Rockies to Mid West and back every week. About 80% of miles are loaded to 75k +. Pretty sure I could do just as good or better with a 13 or 18 speed manual. But have yet to convince the bosses to get me one.

 

I hear that. I'm just st starting to warm up to the idea of auto. If the mileage is better.

 

You only get better fuel mileage with them if you're not driving the manual right. My dad sees 7 regularly around 80k pounds and he gets about 8 around 60k, this is with a 97 fld 120 with an N14 and a super ten. I get 6.5 steady between 85 and 90k with my cat and 18 speed in a 97 W9, did 7 once with a good tail wind. The point is it's all in how you drive the truck and the automatics/automated manuals aren't worth the headache to me, but then I don't like automatic trannys in anything.

 

If a good driver misses one shift in 5 years he
Loses to the automatic.
If he overrevs the motor 1 time he loses.
If he lugs the motor 1 time he loses.
If he grinds 1 gear ever, he loses.
If he gets caught out of gear 1 time ,he loses.

Humans can't beat machinery.

 

One mouse chews one wire, you're fancy smhancy automated crap turns is a brick, not even a close competition to a remotely competent driver.

 

Theoretically yes. My Ultrashift blows shifts every day.
Sometimes it goes to shift, can't find the gear, truck slows down, it goes back into the gear it started from.
Climbing a large hill, holding it in 11th just fine. It decides to go for 12th, can't catch it, drops all the way down to 7th at 2200 rpm, works it's way back up to 11th and wants to do it all over again. So I have to put it in manual mode.