Allison, Sweet Allison, Who Art Thou?

[Oldyeller]

As I posted in the general discussion section, I just bought an 2004 IC bus with a t444e and an Allison. Below is the ID tag on the trans which says '2000' in the top left. I'm assuming that identifies it but which model of the 2000 line is it. I'm going to start researching myself but if someone here has already done the leg work I'd be appreciative for a translation of the tag.

I sure hope I got the right tag. Just now occurred to me that just because it's the first on I found it might not be the only one.

BTW the gear selector has 1-2-4-D-N-R. I once found an Allison manual that showed that pattern, I'll have to see if I can find it again. If I recall correctly it indicates a 5 speed.

[banman]

You is correct! It's an A2000 by the # in the upper left.

I believe the second line starting in the upper left is the SN.
If you go to Allison's website you can plug that # in and learn some more about the internals of your trans. Most of it will be sub-component #'s which meant nothing to me but would to a rebuilder...

[Oldyeller]

Originally Posted by banman

You is correct! It's an A2000 by the # in the upper left.

I believe the second line starting in the upper left is the SN.
If you go to Allison's website you can plug that # in and learn some more about the internals of your trans. Most of it will be sub-component #'s which meant nothing to me but would to a rebuilder...

Thanks Banman, my research got sidetracked after I found the Allison 1000/2000 owner's manual in PDF. Been reading that.

[Oldyeller]

I tried that S/N in the Allison site and it just reiterated the S/N and said its a 2000. I know there are various models of the 2000 (2100, 2400, 2500) so do I assume mine is 'just' a 2000? Everything else on the page is sales stuff unless I'm missing something.

[Catterson]

Originally Posted by Oldyeller

As I posted in the general discussion section, I just bought an 2004 IC bus with a t444e and an Allison. Below is the ID tag on the trans which says '2000' in the top left. I'm assuming that identifies it but which model of the 2000 line is it. I'm going to start researching myself but if someone here has already done the leg work I'd be appreciative for a translation of the tag.

So have you found the translation?

[Oldyeller]

It's a 2000. I got a response from Allison.

[RolesvilleMarina]

I also have a 2000 (now)

and when I was doing my swap I don't recall anything in my research about 2100, 2400, etc

but apparently I learned the other day there is?


So I am also curious what the other numbers mean? is a 2400 "better" than a 2100? Thats kind of joking but seriously what do they mean?


I thought it was all just A-2000

[Booyah45828]

The different 2000's are for different options and internal changes. Changes like different gear ratios, internal park pawls, lower 1st gears, more clutch packs, etc. Some models designate specialty use transmissions too, such as those in trash trucks and motorhomes.

But they're all still a 2000 series allison and operate in similar fashion.

[Ronnie]

I had the idea the 2000 actually has 6 speeds but 6th is locked out? Can anyone confirm this? A bus my friend has(in my shop) is a 2000 series, and governs at 65mph. Which seems good.But wondering if indeed there is a 6th gear to be unlocked. The other threads about 6th gear all seem to be applied to the 3060 trans.

[musigenesis]

I'd love to know if a 2000-series has a sixth gear that can be unlocked. My bus currently shifts into 5th gear (its top gear) at 30 mph.

[Booyah45828]

All 1000 and 2000 version allisons have the planetary gear sets - the internal gears to the transmission, to have a 6th speed. There is a break year and serial number in the mid 2000's where they changed the valve body and components so as to gain the 6 speed capability. Pre-serial number transmissions will have to do a valve body/harness/tcm swap in order to gain 6th, where as post-serial number transmissions can gain the gear with a software change.

I've talked about this before on here, so a search might turn up more details. I've never done the swap, because it costed too much for any of my customers to go through with it. Now that stuff is all 15+ years old and I'm sure the price didn't go down at all.

[RolesvilleMarina]

Originally Posted by Booyah45828

All 1000 and 2000 version allisons have the planetary gear sets - the internal gears to the transmission, to have a 6th speed. There is a break year and serial number in the mid 2000's where they changed the valve body and components so as to gain the 6 speed capability. Pre-serial number transmissions will have to do a valve body/harness/tcm swap in order to gain 6th, where as post-serial number transmissions can gain the gear with a software change.

I've talked about this before on here, so a search might turn up more details. I've never done the swap, because it costed too much for any of my customers to go through with it. Now that stuff is all 15+ years old and I'm sure the price didn't go down at all.

wait so 2000 models have a 6th? I thought it was just md3060??

how do you find out then? although I am sure mine is the old no 6th style

[Booyah45828]

Originally Posted by RolesvilleMarina

wait so 2000 models have a 6th? I thought it was just md3060??

how do you find out then? although I am sure mine is the old no 6th style

Yup, they all have a 6th available internally. Before IIRC 06 you'll need to change the valvebody and it's associated solenoids, sensors, wiring and tcm.

You'll have to get it all cleared through allison to get the 6th enabled tcm files, which like with the 3060, is the hard part in the process. I imagine some in the aftermarket have finally cracked the code and can do it for you without approval letters and all that crap.

If you're capable of swapping your 545 to a 2000, you're capable of the valve body swap.

Truthfully, unless you're geared super tall, you likely won't see any improvement in mpg going to 6th. And it will also likely be too low of an rpm that you'll drop into 5th at every hill.

Christopher has a 6th enabled allison in redbyrd. No idea on the trans year, but you can talk to him about the files. In my experience, the software was always the hard part of the process.

[Booyah45828]

Once again, this has been discussed before in years past, search the forum and it should be there.

[cadillackid]

its much easier to say that none before 2006 have the capability of a 6th gear.. you need to change the valve body / the wiring harness and the TCM to be 6 speed capable.. its more than just a valve body swap.. changing a valve body is not for the faint of heart, it also involves changing the internal harness, external harness to support the 4th gen TCM and of course getting the TCM programmed for your application..



if you feel comfortable working with checkballs and small wiring / solenoids , and the like then a valve body swap is in the cards.. it will cost a couple grand to do.


from what ive seen its only the GMC's that can get away without changing their wiring harness .. suncoast has a 'no wiring' type kit..



there were a couple others thajn I cant find now which were designed for the medium duty market.. those companies may be defunct//




here is an example for the GMC 5 speed allison 1000 (very similar to 2000).. I wouldnt use this kit without first talking to suncoast..



you'll need a medium duty J1939 TCM, whereas this kit likely ships with a GMLAN TCM by default..


https://suncoastdiesel.com/i-3049792...5-6-speed.html

[Oldyeller]

There's more than one way to skin an Allison. You could change the diff. carrier to one with a lower ratio. I was looking into that a while back. Going that route would be cheaper (parts-wise) and simpler than upgrading the trans but you'd have to be careful you didn't go too far (low a ratio) or you'd regret the decision.