Allison techs??

I drove a T800 with an ISL in it with an allison behind it and hauled 78,000 lbs. It wasn't the fastest truck out there by any means but it did do the job. I believe that it was a 400hp rating on the ISL. If you are not going over 48,000 pounds gross than the ISL would do you fine considering that they put ISL's in dump trucks and they haul more than 66,000 pounds.

 

"The bad thing that you can not use transmission to slow down and brake pads wear is doubled."
Sorry Pablo, but that is totally wrong!

The Allison transmission retarder is a very effective way to slow a vehicle without having to use the brakes.
On engines with exhaust brakes the transmission will downshift to keep engine revs high to increase the efficiency of the exhaust brake.

 

I cant say that fuel milage with alisson suffer to be a half of on manual tranny. I would say around 10-15%, but when converter clutch is bad ore torque converter is bad - yep... fuel milage is bad.

Bus drivers say about double difference becouse MAZ and LIAZ make city buses with auto and interstate buses with manual and they did not compare bus with manual with bus with auto in the city. The problem is that city buses got "slow" rear end and when they run over 40 MPH they have really bad fuel milage so they cant surelly say about fuel milage difference.

Ok, about ZF as-tronic. It is amazing this transmissin saves fuel compareing with regular manual transmissions, but all ZF are expencive to fix, autos on cars and buses are expencive too

 

You can get a Allison with a wide range of engine sizes in the T660 and the T800. I brought a truck back from Arizona. It was a T660 with a ISL and a six speed allison. The gearing was a little tall but I was able to go down the road at 75 mph running 1900 rpm. If you get a KW glider which I don't even know if they offer that then you could get factory mounts for the engine on certain models. The T660 had the studio sleeper that was 72" if I remember right. It may seem like I am pushing KW but for the ease of swinging an engine into them with factory options for certain engines makes them more appealing to me.

 

That was with a 32' trailer behind it. The trailer was a flatbed and it was empty. Went from arizona to indiana like that and got 7.4 mpg running 75 mph through the states I could and 70mph through the others. I figure that if you run it smarter than what I did with a load you could easily get 7 mpg out of one of those. Allison's aren't known for their good fuel economy at interstate speeds. They do tend to run at higher rpm's while doing the speed limit. The other guy that followed me back from Arizona was driving a Pete 388 heavy hauler. He was running 1800 rpm with an ISX 15 liter and an allison 7 speed at 75 mph. He had to fuel his truck up evey night. I think that he might have gotten 4 mpg.