Adding J1939 to a 3 box for allison swap

[nikitis]

I'm willing to put in 5-6k into it, not 15-19k. I'm gonna call CAC again and tell them i'm not trying to build a hotrod bus. I just need a used swap with standard converters. If they don't want to work with me on it then I'll obtain what I need and find someone to install it or eventually try it myself.

Questions I have before I do though.

In my recent research (as of today) I noticed the T444E have SAE2 housings, but the AT545 is a SAE3. So I went to look under my bus just now, and I believe I do have the SAE2 to SAE3 Adapter on it. What's to stop me from just bolting on an SAE2 MD3060 directly? Are there flywheel considerations? Torque converter considerations?

 

[cadillackid]

the converter is their KC converter and works excellent... i love the converter well over a pickup truck stock.. harness is expensive.. I think jason charges half that (maybe less).. they put their wiring on it for their throttle box...



the core is because you are not turning in another allison 1000 / 2000 with SAE3 bell.. you wouldnt pay the core charge if you were handing them a dead 1000 / 2000 SAE3 unit.. so if you could buy a broken 2000 series for a couple hundred bucks that has SAE3 bell im guessing you can save the core charge of $1400. Omni is right that the bell and tail are swappable on the 1000 / 2000.. you can bolt on an SAE3 bell t oa GM transmission.. you'd be buying the harness and TCM from CAC.. you'd need the same generation.. they use the 2006-2009 generation transmisisons and TCMs (at least what they did on mine).. their price of $5400 is decent for a fully reman dry transmission... you can find a used one a whole lot less.. I wanted new because i know I drive that bus a ton of miles... im in nearly 8 years and zero issues...



buying a complete bus is what rolesvillemarina did on this board.. in fact he was so thorough he re-sold the donor bus as a running driving bus with an AT545 in it... he hasnt had any issues that i know of...


I suspect a stock 2000 series with TCM (3rd gen) with the AU converter would get you up and running with a 5 speed alot cheaper and most likely succesfully... 6 speed you'd need to find one from a VT365 or DT466E (post 2006) 4th gen (not a maxxforce..they use SEM).. and you could probably do all the same and have 6 speeds.... SAE3 bell was by far the most common usage on school busses...

 

[cadillackid]

I'm willing to put in 5-6k into it, not 15-19k. I'm gonna call CAC again and tell them i'm not trying to build a hotrod bus. I just need a used swap with standard converters. If they don't want to work with me on it then I'll obtain what I need and find someone to install it or eventually try it myself.

Questions I have before I do though.

In my recent research (as of today) I noticed the T444E have SAE2 housings, but the AT545 is a SAE3. So I went to look under my bus just now, and I believe I do have the SAE2 to SAE3 Adapter on it. What's to stop me from just bolting on an SAE2 MD3060 directly? Are there flywheel considerations? Torque converter considerations?

if i remember right the MD3000 series has the same bolt pattern and offset as an MT643.. dont quote me on that.. it just seemed familiar when I looked at going with an MD3060 in my DEV bus.. the part numbers for spacers and flexplates seemed the same.. this would mean youd need that nearly unobtanium spacer ring that the T444E used to run an MT643.. and the flexplate.. if you are lucky your 545 going to your 444E will have a converter bolt pattern adapter ring on it... however that doesnt cover the SAE2 spacer ring... 444E were sold with MD3060's they just werent real common.... the 444E was considered the budget engine and the MD3060 was considered the expensive transmission.. so not many had it.. thiough ive seen a couple RE amtran busses that had 444E and MD3060..

 

[nikitis]

if i remember right the MD3000 series has the same bolt pattern and offset as an MT643.. dont quote me on that.. it just seemed familiar when I looked at going with an MD3060 in my DEV bus.. the part numbers for spacers and flexplates seemed the same.. this would mean youd need that nearly unobtanium spacer ring that the T444E used to run an MT643.. and the flexplate.. if you are lucky your 545 going to your 444E will have a converter bolt pattern adapter ring on it... however that doesnt cover the SAE2 spacer ring... 444E were sold with MD3060's they just werent real common.... the 444E was considered the budget engine and the MD3060 was considered the expensive transmission.. so not many had it.. thiough ive seen a couple RE amtran busses that had 444E and MD3060..

Do you still require a spacer if it's sae2 to sae2?

Or just with an MT643?

 

[cadillackid]

Do you still require a spacer if it's sae2 to sae2?

Or just with an MT643?

the MT643 is SAE2... it all has to do wit hthe converter offset.. (how much does the converter stick out from the SAE2 mounting flange.. the 3060 is an SAE2.. youd still remove the 2 to 3 ring.. youd have to look up the offset measurements to see if the converter sticks out less on the 3060 than the 643.. I thought they are the same..

 

[nikitis]

Just seems kind of odd though right? To develope a sae2 standard t444e housing and not make room for a converter and transmission sae2 Bell housing mount and it not fit. They should be designed to work with out spacers especially for a default converter. I can see needing spacers for upgraded converters with more thickness. Are the standard torque converters on the bus transmission bigger than usual?

 

[cadillackid]

Just seems kind of odd though right? To develope a sae2 standard t444e housing and not make room for a converter and transmission sae2 Bell housing mount and it not fit. They should be designed to work with out spacers especially for a default converter. I can see needing spacers for upgraded converters with more thickness. Are the standard torque converters on the bus transmission bigger than usual?

there were a lot of different transmissions.. you have to remember there were manual transmissions as well.. and in the truck side of things in 94 the majority of medium duty work trucks were stick shift.. so I suspect that the housing is perfect for a clutch and the most common spicer manual transmissions... i also believe that housing is the same as was used on the IDI which came out in the 1980s so even a lot of school busses were stick then... the MD3060 wasnt even out when the housing was developed.. the MT643 was out but likely the minority of vehicles built... the provision for an AT545 was an SAE2 to SAE3 adapter ring and a spacer ring from the flywheel to the 545 converter.. so not a big deal..



the fact these MT643 spacer rings are tough to get speaks volumes about how the correct design was picked.. it means not many of them were ever used..