Twin Stick Transmissions and Modern Powerplants

That, and fuel economy.

 

No sir. Detuned engines do not get better fuel economy than that same engine at the factory setting. A company will buy a bunch of trucks with 455-515HP and detune them to 350-430HP. Brand new truck runs like garbage and constantly is in the shop. Fuel economy suffers and there’s all kinds of issues with the DPF. The manufacturer’s shop will reset the ECM back to factory specs and the truck will run fine. As soon as it gets back to the trucking company, once again it is detuned and will be back in the shop I no time.

 

There is a company that still makes the Spicer 6x4, but they ain't cheap. Still, I wonder WHY you would want such a tranny behind a high-horsepower modern engine? I once drove a 6x4, and it is NOT something I'd ever want to have with any 400+hp motor. Back in the old days, a 'high horsepower' motor was like a Cummins 290. climbing a 12% grade at full load, you NEEDED all those close-spaced gears. Today, with anything more than 400hp, a simple 10-sp will suffice. You could even do OK with a 9-sp...

FWIW, I'd heard about guys back then driving teams, where BOTH drivers would work the sticks together on really steep climbs, to avoid mis-shifts on those double-stick shifts. They were THAT difficult to double-shift, especially on really steep climbs...

 

There is a small specialized heavy haul outfit in these parts that just ordered 4 389’s with 4 speed aux boxes behind big X15 power. Can’t really call them Brownies anymore. Spicer teamed up with Tremec a handful of years ago to make them. Owner of this outfit was a longtime friend of Marvin Rush and like my uncle and a few others around here bought trucks from him back in the 60’s when he was taking build orders from the back of his station wagon at the old San Antonio Union stock yards and then personally driving them back to the only factory in California.

 

It all depends on what your dragging behind you... Just last summer I was in a 2007 W900 with A 550hp CAT, an 18 speed, and 3:36 rears. At 106,000 pounds pulling an A-train tanker, I NEEDED every single hole I had, and often wished for another 2 or 3, running some of the grades I took it on. Getting back into some of the places I had to go.

 

You and I both know that is true when a truck is properly driven, but companies seem to think that there is an inverse relationship between horsepower and fuel economy.

 

I worked for a company in 07 that bought brand new trucks with 455HP and 13 speeds that took the trucks, detuned them to 350HP and 9 speeds. You cannot detune them more than 10% of the factory settings. Brand spanking new truck I had, 455Cummins. Stayed in the shop. Fuel economy suffered 1.5-2 mpg. They sent me west on 70, and had to get towed out of the Rockies. 4 times, I got towed out of the Rockies. Finally, the dealer checked the ECM tune, reset it to 455, and the truck ran fine. When I got to our yard in Houston, they detuned the truck back to 350. Truck broke down. Eventually, the dealer realized what the company was doing and threatened to void all warranties.

I am not a diesel mechanic, but I know from experience that there comes a certain point that detuning an engine will severely hurt both performance and efficiency. Soon after this breakdown, my dispatcher had me brought into the office and had me talk with some woman in the office about becoming an owner op, and she was concerned about success. This woman wanted me to look into their lease purchase program as a step before going to buy my own truck.

“You do well as a company driver. Why do you want to be an owner op or lease operator?”

So that your shops cannot touch my truck without my permission.

“Well, they do the lease trucks the exact same way that they do the company trucks..”

Really? Glad you said that. There’s no way in hell I would pay for a truck that your shop idiots can jack around with.

She got furious. “YOU TRUCK DRIVERS ALL COME IN HERE WITH YOUR OPINIONS, BUT IT’S A PROVEN FACT THAT YOU WILL BE MOST SUCCESSFUL WITH OUR SYSTEM!”

You must be the idiot that wrote the bean counter engine tune for the trucks. I’ve been stuck in Denver Colorado for two weeks! They towed me out of the Rockies 4 times! Brand new truck with under 20k miles! I know you think you’re intelligent, but you don’t know what the F…!

Dispatcher comes running up, and office people are staring in horror, “ Six! Come on dude! We gotta go!”

Curses, foiled again.

 

So what are they called nowadays? I'd sure like to look them up.

Man, that's cool! I love learning new things about San Antonio's history.

 

I've seen some new bed trucks with them, but they are air shifted.