1 engine 1 Trans question

[Eric]

First off 1991 Ward bus
5.9 cummins.
At545

So when starting the bus it's "choppy" then abruptly it smooths out and all is well(engine) and no unusual smoke either

2nd

Is it better to manually shift the 545 or let it do it's thing... Seems it shifts mighty fast through the gears .... Well just like a school bus

As usual
Thanks in advance
Eric

[chev49]

i dont get what you mean except maybe allison writings say to not just drive off without warming up the transmission... i know i read that on their site somewhere, when i was looking up something for a 643

[opus]

With my 643 you tell it where to shift, with the throttle.  If you come off a stop with a light throttle, it will shift through the gears plenty quick.  You'll then be in high gear with nothing.  Get right on it and see if it shifts properly.

Not sure if you can compare the 545 with the 643, but you get what I mean.

[Eric]

It does shift down when I throttle it downshifts but my old 730 in my previous coach it was better to shift it myself

[Seayfam]

Eric,
As far as your 5.9 goes... I think you have a problem with your grid heater. That is a common problem. It probably does it on a cold start and not the rest of the day? It is a cheap and easy fix.

Sent from my GT-I9100 using Xparent Green Tapatalk 2

[chev49]

my 643 i mainly use the d and r.... except in hills... as previously mentioned, shifts quickly. like it better than my older allison.