Auto Shift Transmissions

Yeah, gotta go along with that. Aliison's in trucks is not like the auto in a car or pickup. The Allison does use torque converter, but their is a lockup at something like 2-3 mph so that the trans is not using the TC after that point. On a auto shift, the computer is basically "floating" through the gears. There has to be a short point where power is let off the engine to allow the trans to shift. All done very quickly, but it is still the same principle as any driver floating the gears on a manual. Now the newest auto shifts are going to dual clutch setups that can anticipate the next gear needed and can avoid this and be more like an automatic, but it still is not like an Allison.

And the Allison TC10 has the same 5 yr/750,000 mile warranty as any manual or auto shift out there, so reliability much not be an issue.

The Allison doesn't need to have power reduced on the engine for a brief moment to shift. It can shift under full engine load. And the avoidance of that small delay can help considerably under a hard pull. There is no power let off.

And Allison has been at automatics far and away longer before the auto shift was even a thought in any of the other OEM's heads. They have been used in everything right on up to some very serious heavy haul in hill country. See if this doesn't prove the point.... Most folks who pull this kind of stuff do not frequent forums like this....

http://www.youtube.com/watch?v=5svkrWrl-RM

Comparison of the Eaton Ultrashift and the Allison on a 25% grade....

http://www.youtube.com/watch?v=3rvTq0eXwdU

Then here is a vid on the test drive of the Allison TC10 done by Fleetowner mag....

http://www.youtube.com/watch?v=ip1C6AEo3f8

 

Thank's for posting the links Cowpie, beat me to it. If there was a variable for the Allison that impacts it negatively, I'd say the number one thing would be running too hot, not doing transmission fluid and filter changes, OR possibly too much horse power than what the trans is rated for. There's all sorts of articles out there, for example Greyhound getting over a 1 million miles on a B500 Allison mated to a Series 60. When they opened it up, very little to no wear. This is a highway application, but you get the point.

The Allison HD4060, which is the 6 speed version, you can accelerate and not use full throttle and it is still very respective. The only thing that bothers MPG's on the Allison is WOT full acceleration, go easy on the throttle and you have stellar MPG's. Once you're on the highway and it locks up, you're turning low RPM's, hit a hill or a hiccup and it down shifts. The sounds of a Series 60 and 6 speed Allison are simply music to a persons ears. The thing I enjoy the most, is feeling the brute power and feeling how it accelerates. You can't get that with a manual or auto shift.

 

It is strange they only compare it to The Eaton Ultrashift and not to a I-shift or a Detroit.

ANd where are their tests with semi's?
All you see s straight trucks.

Which is what you don't want.
With a modern engine,which the OP is talking about,you want it to not downshift but pull as long as possible on torque.

Now do i say that the Allison doesn't have any uses?
NO,maybe for garbage trucks and the like they have their use but on road semi's ???

 

daf105paccar, you're really failing at convincing anyone whythe Allison is bad. If you look in their channel, they have many videos:

1. A super market chain: https://www.youtube.com/watch?v=1dPPCJKDgeo&list=UUIF8AGfWwRIryZNDaAEdn3A

2. A logging company: https://www.youtube.com/watch?v=uS46wQRWs6E&list=UUIF8AGfWwRIryZNDaAEdn3A

3. A tanker company: https://www.youtube.com/watch?v=MDJVupg33bI&list=UUIF8AGfWwRIryZNDaAEdn3A

4. A trucking company: https://www.youtube.com/watch?v=iMzFaCSN26A&list=UUIF8AGfWwRIryZNDaAEdn3A

I should have reiterated the down shift on the hill or hiccup. The only time it will down shift is if you start dropping speed and your RPM's drop low enough that the gear is to high. I failed to make the point that when climbing a hill, it down shifts instantly and smoothly and you still have full boost.

I still don't get why you hate the Allison, no real reason. The I-Shift is a decent transmission, but still I'd take the Allison.

 

Allison's got a few transmission specs that can take as much as 900 hp input, with 1950 ft/lb torque at first and (if I am reading their spec sheet correctly) a max input torque of 3000(!). In my current gig, I drive one frequently, in severe back road and offroad usage, in a straight truck that bends 80k loaded, and sees grades in excess of 10%. This one happens to be in a Mack, unfortunately with the exceedingly limp-wristed 400hp MP7 motor, but keeps right on pace with our 500hp ISX/18spd rigs until it sees a hill. Another hundred horses would solve that, though.

Zero problems. Never mis-shifts, ham handed drivers don't wreck anything except the fuel mileage, rarely breaks traction except at WFO, where it'll actually squeal the tires on a shift. Just keep it cool, and change fluid/filters at specified intervals. If spec'ing an auto, Allison's got my vote.

 

Try the first and last video I posted. Or did you not even look at them. The first video is the heavy haulers one. Best I can tell, that is a class 8 semi truck that is pulling that 375,000 load. And the last one is the one the Fleetowner mag did, and that is with a International Prostar. Again, last I heard, the Prostar was offered as a class 8 semi truck. At least I sure see a lot of them. You might want to re-watch the vids (or watch the first time if you didn't). And there are a lot of other vids and such about the Allisons. Wasn't going to post all of them. You do have to do some of your own legwork once in a while and not be like one of those folks that loves Obama and thinks he is going to provide them a cellphone and car and pay their mortgage for them.

 

Cowpie, this was the same guy trying to convince every one that the Pacar engines were a quality product.

 

Oh yes they have, they've happened to me and not with just one truck, I've probably driven 20 of them with this company and not a one worked like it should.
It's unnerving to have the thing go out of gear starting down a big grade and not be able to recover, I've had this happen numerous times rolling well over 100,000lbs down a 6% grade.
Getting on the brakes as quick as possible and stopping the truck completely is all you can do, sometimes it will go back in gear once you stop but other times you have to set the brakes get out and shut all the power off at the battery to reset the computer.
Never had a problem with the Allisons we have and they do pull steady on the hills and from stoplights as freightlinerman said, no road-speed lost on shifts like the auto-shifts do.
Often if you let an auto-shift shift itself in drive up a hill it will either upshift then bog down because it took too long or it will try to shift but go right back in the same gear with speed lost.
Believe me I deal with this every day hauling heavy loads up and down big hills.

 

Pics or it clearly didn't happen. Others have reported nearly having an accident. There is a video on youtube a guy holding a gear going down hill with the jakes on, when it shifts to the highest gear even though its being held(not video of the event, but describing it). The scariest grade I've been on was a 7%, rule of thumb, 6% percent, drop 1 gear, 7 percent, drop 2 gears. BUT, in reality that 7% should really drop 3 gears, on the event in any truck regardless of transmission, the jake brakes were to fail. I could only imagine turning 2,100 in 8th gear(on a 10 speed) down hill with the jakes on high, then the transmission upshifting. Not good.

 

Cowpie,i am bit disappointed in you that you have to result to personal insults.(and lets not kid each other,you meant it as a insult)
I taughed you were smarter guess i was wrong.