4106 with 4 speed auto?

[shaneblaser]

I am going to look at a 4106 with a 6v92 and a 4 speed auto? I do not see any talk of other  auto trans than the v730 (and the 2 speed).

Are there 4 speeds auto that fit int he 4106 ?


Thanks

Shane

[HB of CJ]

Could it be the three (3) speed auto that has that lock up clutch in second, (2nd) or third? (3rd)  That might make it sound, feel and tachometer operate like a four speed.  First convertor, (1st) second convertor, (2nd)  then second lock up, (2nd LU) then third, (3rd LU) or high lock up.

I also think or remember some of the 730 automatics could be modulated to have the lock up function in first gear?  This would be very handy coming down slow steep grades where a Jake Brake would be nice.  Like already said better before me, the 730 is like a 740 only with no first gear? 

Different models within a family also had different options.  Some heavy fire apparatus had the older HT740 4 speed Allision that had the lock up option in every gear along with the convertor mode to increase acceleration.  Those trannys felt and sounded like a 7 or 8 speed.  HB of CJ (old coot)

[shaneblaser]

Thanks,

I had thought they might have taken the converter locking for an extra shift, I will find out when I go look at it.

Is there an easy to see model number on the trans ?

[RJ]

Thanks,I had thought they might have taken the converter locking for an extra shift, I will find out when I go look at it. Is there an easy to see model number on the trans?

Shane (?) -

HB's description of the V-730's upshifting is accurate (1C-2C-2L-3L) which makes it feel like a 4-spd.  Common error by unfamiliar folk.

When you open the engine compartment, if you look to your right and see a giant aluminum salad bowl tipped on end, it's a V-730.  I don't remember if the ID plate is on the curb side or the driver's side of the transmission, either way it's a flat plate about the size of a 3x5 card.

FWIW & HTH. . .

[TomC]

To go one step further, I can make my V730 sound like a 5spd. I can get lockup in first by pulling the selector to 1 and accelerating with my foot about an inch off the floor. So I can get 1C-1L-2C-2L-3L. Good Luck, TomC

[Bill Gerrie]

Tom
I have a V731 and no matter what I do it is c-1, c-2, L-2, L-3. No way to lock in 1.

[Purplewillie]

V730
Mark

[luvrbus]

New Flyer used a ZF 4 speed on a V drive

[TomC]

To bad Allison didn't use the same system as ZF-which took one of their normal 4spd automatics and added a Vdrive to it-which by the way ran a normal right hand engine. Good Luck, TomC

[HB of CJ]

Since I do not know I will ask.  Are all 730 three speed Allisons capable of being locked up in first gear?  Or only some?  Can they be re modulated to do so?  This might be a deal maker/ breaker regarding steep grade mountain performance with a Jake Brake. 

I can see this would be cool either going up or coming down a very long slower steep grade.   Reduced transmission oil temperatures going up and less brake usage/ heating coming down when using the Jake Brake come to mind.  Thinking safety here mostly.

Also;  Are most or all HT740 4 speeds capable of being locked up in first gear?  Same reason, only a lower gear than the 730.  If memory serves, some older heavy fire apparatus would lock up in every gear accelerating but I don't know about decelerating.

Thank you.  HB of CJ (old coot) I love this Bus Conversion Forum!

[RJ]

To bad Allison didn't use the same system as ZF-which took one of their normal 4spd automatics and added a Vdrive to it-which by the way ran a normal right hand engine. Good Luck, TomC

Yup, and that angle-drive attachment to the output end of the ZF practically bankrupted Cummins and Flxible with warranty claims when they first came out.

Seems the aluminum casting that housed the bevel gears wasn't thick enough, and as the powertrain heated up from normal transit use, the case would expand to the point that the bevel gears would start skipping teeth.  The next thing you knew, the case would come apart and the bus would be dead in the water.  NYC had over 200 of them fail w/in the first year of revenue service!

ZF solved the problem by using cast iron instead of aluminum for all later production angle-drive installations, and that became the most dependable part of the gearbox.

As for the gearbox itself. . . talk to any big transit agency's shop about the ZFs.  You'll learn a lot.

FWIW & HTH. . .

[Barn Owl]

This might be a deal maker/ breaker regarding steep grade mountain performance with a Jake Brake.

Not a all, it is a wonderful setup. I go up and down some extremely steep grades and I don't recall ever using first gear to creep my way down. Also the Jake is still effective even when the tranny is not locked (At least on the light 4106 with the v730, not sure about the VS-2).

[TomC]

If you have a R-N-3-2-1 shifter, then you can pull the gearshift to first. It will hold in first up to 2,400rpm where it will shift to second to keep the engine from over revving. When in first, and you are going down a hill, the torque converter should be locked up for maximum Jake brake.
We were in the Sierra Nevada's going over highway 4 where we had the bus in 1st gear going up and 1st gear going most of the way down. I got to the bottom of the grade without smoking the brakes. Good Luck, TomC

[shaneblaser]

Thanks for the replys everyone