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TomA 06-05-2020 06:55 PM


Originally Posted by Kubla (Post 390578)
I was informed tonight that ZF made a transmission to replace the V drive allisons in city buses, did not get any details though

That's the Ecomat, which is a great transmission, but its huge and heavier than an Allison VT730. Also fully electronic, and expects a fair amount of data from the engine to work. ZF have a number of different tailshaft angles and configs for it, and if you used a lighter engine, like a Cummins 5.9, it would THEORETICALLY work. but that's a whole lot of engineering to hang that from the roof of a GM coach (yes, that is how the engines are mounted,) and make it work at all let alone be a good set of compromises. The factory package from the 1950s is already a good, proven and durable set of compromises, so the bar you're trying to get over is very high. Worst of all, you're starting with about $50k worth of stuff (built on different continents in different centuries) on a major undertaking that nobody knows anything about.

To get from the back of a napkin sketch to driving it down the road would take YEARS and the likelihood of failure is very high. That's something to do if you already have a serviceable bus you like and use, and you want to prove something to yourself or the rest of the world. As Crown Guy wisely says, if you want to use it, just buy a nice example with the best available equipment and go from there.

Kubla 06-05-2020 07:13 PM

I know all about putting electronic controlled transmissions in buses that had a mechanical one, spent much time reading Christopher's thread on putting one in his redbyrd, and I have an allison 2000 for my bus, paid more for the wiring harness than the trans

TomA 06-05-2020 07:19 PM

Crystal, why don't you consider taking it at right angles and going for something like this:

Nice, clean, low mileage bus with a gem of a drivetrain, no emissions and tons of space. Keep the roof and the windows as they are, and start your conversion. This one is priced high, but it is a pristine example. In my experience, paying too much for the best available vehicle usually works out to be a bargain...

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