When did AT545 stop being used in school busses?

[t-chuck]

Recently I have seen a few ads with AT545 transmissions in 200x busses.
What year did they stop making/using the AT545?

[cadillackid]

2003 was the last manufacture year for AT545... the allison 2000 wasnt released until mid - late year 2000 so its common to find 00,01,02 busses with 545.. and even a 03 or 2 though rare

[Booyah45828]

I saw an 04 with one once, on a isb 5.9 cummins.

The engine was an 03 model though, not an 04 common rail, so it was likely an 03 built transmission too.

[cadillackid]

Definitely have seen year-behind chassis in school busses before. My red one is like that in someways . 99 and 00 were pivotal and it has some 99 parts that fit and some 00 that fit.. so seeing an 03 drivetrain in an 04 bus doesn’t surprise me

[fo4imtippin]

I have an 03 Bluebird. I went through their portal for all front engine buses of the same year. None of the All Americans had a 545. For the TC2000, it was like 10% 545, 70% 2000series, 20% 3000series. They were really phased out around that time.


Really weird the other day, i was helping a guy on reddit identify his motor. He had a 2006 common rail Cummins 5.9 in a bus. It was real weird. His air compressor and hydraulic pump were mounted to the bell-housing side. I have never seen the common rail 5.9 in anything on-road industrial. After the 24v VP44 ISB, Bluebird seemed to use Cats until the 6.7 Cummins came out.

[cadillackid]

didnt some of the FS65's get CR 5.9s for a short period? I mean those are freightliners but ,ightve been a stop gap for Bluebird

[fo4imtippin]

Originally Posted by cadillackid

didnt some of the FS65's get CR 5.9s for a short period? I mean those are freightliners but ,ightve been a stop gap for Bluebird

I haven't seen them in the FS65. I have seen a lot of them with Mercedes during that period. Its possible the bus i was looking at was an FS65. He was sending pictures of the engine only. Just thought it was odd.


It looks like Marine engines (QSB) went from the 12v to the common rail 5.9 and skipped the VP44.

[t-chuck]

Thanks , I saw a 2006 RE300 with a rebuilt AT545 and was wondering if that was even possible.

[Booyah45828]

Oh I've worked on ones that were equipped with the common rail 5.9.

They were rear gear, like you saw, and I wouldn't call them rare by any means. I believe dodge was the only ones to use front gear stuff with common rail, as most commercial stuff was rear gear when it went to common rail if I remember right.

I thought qsb went rear gear as well, but they might have been both too, I'm not all that familiar with off road stuff.

I just know we had cats and cummins engines in those years, seemed about a 50/50 split. I'll have to ask around as to why, maybe it was cheaper to go cat, or maybe it was an availability issue, but they definitely were installed.

[fo4imtippin]

Originally Posted by Booyah45828

Oh I've worked on ones that were equipped with the common rail 5.9.

They were rear gear, like you saw, and I wouldn't call them rare by any means. I believe dodge was the only ones to use front gear stuff with common rail, as most commercial stuff was rear gear when it went to common rail if I remember right.

I thought qsb went rear gear as well, but they might have been both too, I'm not all that familiar with off road stuff.

I just know we had cats and cummins engines in those years, seemed about a 50/50 split. I'll have to ask around as to why, maybe it was cheaper to go cat, or maybe it was an availability issue, but they definitely were installed.

Good to know. Was it certain manufacturers or models with the CR 5.9? I wouldn't mind a bus with that motor.


(Sorry to hijack this thread btw)

[cadillackid]

Originally Posted by t-chuck

Thanks , I saw a 2006 RE300 with a rebuilt AT545 and was wondering if that was even possible.

probably wrong tag.. the ECM-II which was used in 04+ motors doesnt even have an AT/MT trans setting...

[Booyah45828]

Most of the buses we have are predominantly bluebrid AAFE's, with a handful of internationals.

Apparently in 2005 bluebird offered only the c7 in FE's. I believe by 06 the ISB was added back. So 2004 yes, 2006 yes, no 2005.

Still, I remember working on at least one common rail because I had to change the lift pump in it, and I remember struggling to find it because it was located behind the ecm up towards the front of the engine. They didn't use the same carter pump use by the vp44 engines that we changed by the hundreds, but I still remember it vividly.

[fo4imtippin]

Originally Posted by Booyah45828

Most of the buses we have are predominantly bluebrid AAFE's, with a handful of internationals.

Apparently in 2005 bluebird offered only the c7 in FE's. I believe by 06 the ISB was added back. So 2004 yes, 2006 yes, no 2005.

Still, I remember working on at least one common rail because I had to change the lift pump in it, and I remember struggling to find it because it was located behind the ecm up towards the front of the engine. They didn't use the same carter pump use by the vp44 engines that we changed by the hundreds, but I still remember it vividly.

Crazy stuff. What a weird period be be manufacturing diesel vehicles. I don't mind working on most of the stuff in the Front Engine. Only thing that is most irritating is the cold side of the block. A maze of stuff with the injection pump, fuel filter, air compressor, lift pump, and ECU. All pretty close to the frame rail. Although, the AA drop frame may make this better or worse. I'm debating moving the ECU off the block to the frame rail. I'm also debating moving the lift pump further back on the frame rails by the racor filter and delete the block fuel filter (maybe adding a low micron filter in front of the lift pump). Do you know if there was a reason when cummins put out the service bulletin for the VP44 that they didn't recommend doing any of that? It appears on my bus, they just added a pressure sensor linked to the check engine light. If my pump started to burn out, i would at least try to clean this all up. My original plan was a FASS pump, but im trying to spend some money on the conversion and ill just monitor the pump pressure for now.

[Booyah45828]

I think the pressure sensor add-on was a retrofit cummins paid for. While the lift pump would function better farther back, it wasn't deemed "necessary" and therefore wasn't done. They make jumper harnesses that you could likely add wire to in order to relocate the pump wherever you'd like to put it. IMO I'd put it next to and after the primary filter/ water seperator if you wanted to relocate it. The stock secondary filter seems to work good enough, so I'd only ditch that if you were upgrading to a 2 micron cat filter or something similar.

Some things are easier with the drop frame, some stuff is more difficult, it just depends on what you're trying to access. Working on an FE isn't impossible, it's just more difficult compared to an RE or CE.

If you're going to move the ecu anywhere, move it someplace cool. Some of the dodge guys mounted it parallel to the ground to catch air flow from the fan. I'm not sure if that really helped anything.

I'd say monitor the pressure and see. The fass stuff is nice, but I wouldn't consider it bulletproof, and it's not cheap either. We've had luck with the airtex style pump upgrades over the carter unit fwiw. They flowed more fuel/higher pressure and seemed more reliable. Those used to be purchased for 100 bucks or so years back, but that's likely all changed since.

A plethora of info on the internet about the vp44, lift pumps, etc. A lot of times it's hard to decipher what's legit, especially when picking through 20 year old info.

Most of the vp44 fleet has been retired for us. Now repair work is seemingly nothing but emissions issues. Times were a lot simpler(and cheaper) back then.

[Gorzie]

What transmissions beside the 545 could I swap in to my 1997 (1998 model year) that would not require a computer upgrade. Is the MT634 the only other option without?

[Booyah45828]

Originally Posted by Gorzie

What transmissions beside the 545 could I swap in to my 1997 (1998 model year) that would not require a computer upgrade. Is the MT634 the only other option without?

Without a computer of any type you're limited to either an mt or at series. There are numerous transmissions available in those two series units. 4 and 5 speeds, different lockup schedules, different gear ratios, etc.

If you have a t444e like your profile suggests, I don't understand the aversion to a computer. You've already got on running the engine, and the electronic transmissions from allison are head and shoulders better then the older mechanical units. Plus you get an overdrive gear(or two) to boot. And like I said, your engine is already computerized, so you've already got the computerized headaches on the bus already.

Some people prefer mechanicals so they can fix it themselves, the problem is that few people nowadays would know how to diagnose or fix a trans issue themselves anyways, so I don't understand that mindset.

Being a 444e, christopher would be the go-to guy on here regarding the swap and compatibility, as he went very in-depth on his when he converted his redbyrd bus over.

[Gorzie]

Sorry I was not clear. Yes I have a T444E. I have no trouble with computers I am wondering if there a transmission that I would not need to get a new/different/upgraded computer. In short my existing computer.

[fo4imtippin]

I dont think i have seen the AT545 with anything other than a SAE3 bellhousing. I think all the MT643 had SAE2. The AT545 and MT643 are the only two Allison automatics without their own computer. You can:
1. Swap in a manual with SAE3. Eaton makes a 6 speed.
2. Add an Allison 1000/2000 with a tcm and some programming. Redbyrd thread for details

3. Swap the bellhousing and adapter plate and bolt on an MT643 with no computer.

[Gorzie]

Originally Posted by fo4imtippin

I dont think i have seen the AT545 with anything other than a SAE3 bellhousing. I think all the MT643 had SAE2. The AT545 and MT643 are the only two Allison automatics without their own computer. You can:
1. Swap in a manual with SAE3. Eaton makes a 6 speed.
2. Add an Allison 1000/2000 with a tcm and some programming. Redbyrd thread for details

3. Swap the bellhousing and adapter plate and bolt on an MT643 with no computer.

Thanks.

I would like to get that 5 or 6th gear to get some lower RPMs when heading down the highway. Also I would like something I don't have to worry about getting to hot when I eventually head over some mountains. Maybe even add an electronic retarder. I am not in a rush as my 545 is working fine now. Just looking for my options before I NEED to swap.

[Booyah45828]

I'd go with a 2000. You should be able to use your engine ecu as is. Chris upgraded to the latest ecu unit from navistar for the t444e, and you'll find that you'll probably want to do that as well. That's not a big issue.

Read the redbyrd thread.

And then read this thread https://www.skoolie.net/forums/f37/t...ons-29535.html

Rolesvillemarina swapped a allison 2000 for an at545 on his vista by purchasing a similar bus and swapping the parts. IIRC he resold the parts bus and broke even on the deal. A parts bus is the best bet as it will have all of the parts that you should need, and after reselling(even if it's at a loss) you'll be money ahead vs buying the parts at retail.

How rolesville did it with the parts bus is how I would do it. To pull off a swap like this without a parts bus you'll be buying every last component needed, which will require a lot of time, patience, and knowledge. Whereas with a parts bus it will be mostly swapping components from one to the other. It will still be work, but much less mental work IMO.