allison swap now it is my turn in the driveway

[magnakansas]

I have the 545 and going to buy a 2500pts I hope this dude has all the parts.

william

[cadillackid]

welcome to the Club!!!!!!!!!

[turf]

congrats!

aww the memory of my 545 hitting the ground hard as i removed it the first time

good times


good luck on the swap!

[Mountain Gnome]

Originally Posted by magnakansas

I have the 545 and going to buy a 2500pts I hope this dude has all the parts.

william

I surely want to know about the yolk match-up. Does it fit the splined shaft, and does it fit the rear-seal? Although I should be able to find out myself in a couple weeks.


I'm envious!

[cadillackid]

I took the same yoke off my 545 and stuck it right on my 1000..

[cadillackid]

Originally Posted by Mountain Gnome

I surely want to know about the yolk match-up. Does it fit the splined shaft, and does it fit the rear-seal? Although I should be able to find out myself in a couple weeks.


I'm envious!

the only time I check my Yolks is right before I beat em and pour em in a buttered skillet

[Mountain Gnome]

Originally Posted by cadillackid

I took the same yoke off my 545 and stuck it right on my 1000..

Yes. I've seen that here. I'm just worried that the 2000 or the 2500 is different. Because no one has shown me why they are different model numbers except for the 2500 having different gearing.


2500HS = Highway Series
2500PTS = Pupil transport system


So I can see that there is something different, the valve body and or the software controls the tranny a bit different.


What is different between:
1000HS

2000HS

?



?

[cadillackid]

as long as we are dealing with Medium duty 2WD stuff , no MH (motorhome units) (no transfer case and no GMC units).. the mate up will be the same.. SAE3 bells are the most common by far (until you get to the 2400, ive seen those with SAE2 in trash trucks)..


GM did some different stuff with their versions, the MH versions all have parking Pawls.. most times the SAE3 units wont have a parking pawl.. I had one put in my 1000, though ive never installed the shifter to use it.. (I bought the shifter just havent put it in)..


torque converters.. theres lots of them but for medium duty they are very similar in their stall.. if buying a used unit the 2500 PTS was by far the nost common in a school bus.. if going new you can have it built for whatever you want.. (which is what I did.. had mine purpose built knowing id eventually be tuning the engine and driving lots of miles)..

[musigenesis]

The buses I drive at work (year-old Thomas C2s) have a switch where you can set the engine braking to "LO" or "HI" (on "HI" it makes the bus really jerk when the transmission downshifts). Is this something common to the 2500 PTS or do you guys know anything about it? The brochures that came with the buses describe the transmission as a "2k".

[cadillackid]

Depends on what they are using for “engine brake” it could be a function of the engine and trans together.. shutting down a VGT turbo, raising the shift sequence and then a slight flare on a downshift results in a good shudder in an allison ..

[Diverdude0075]

I would try to get the whole donor bus or access to it. ECM, TCM, trany harness, etc. may come in handy. Look at the emergency brake setup on both. One could be air brake and the other hydraulic for example. This site was key to swapping my 545 to the 2000. I put 1500 miles on her a few weeks ago with no issues and towed an old F100!

[Trooper2]

Originally Posted by cadillackid

as long as we are dealing with Medium duty 2WD stuff , no MH (motorhome units) (no transfer case and no GMC units).. the mate up will be the same.. SAE3 bells are the most common by far (until you get to the 2400, ive seen those with SAE2 in trash trucks)..


GM did some different stuff with their versions, the MH versions all have parking Pawls.. most times the SAE3 units wont have a parking pawl.. I had one put in my 1000, though ive never installed the shifter to use it.. (I bought the shifter just havent put it in)..


torque converters.. theres lots of them but for medium duty they are very similar in their stall.. if buying a used unit the 2500 PTS was by far the nost common in a school bus.. if going new you can have it built for whatever you want.. (which is what I did.. had mine purpose built knowing id eventually be tuning the engine and driving lots of miles)..

I am working to track down a 1000/2000 trans to replace the 545 behind my 93 12v. If I understand your post above as long as the trans has the SAE3 bellhousing, it does not matter what engine it came off of ? In looking around the local market we have lots of non Cummins Allison transmissions available which would make my life a bit easier.

[Jolly Roger bus 223]

thats the easiest but you can get a 2-3 adapter plate and a few more issues to make them work.
and if i remember right the torque converter will still work but there is something extra with the flywheel because of the spacer and i might have those two backwards.
havent done that swap yet but have researched it a few years ago.
and i might have vehicles mixed up because i am in the middle helping my son build and swap a dt 360 into his f250 with a ford tranny.
if your not following it check out a tranny problem thread from mountain knome.
him and caddilac have already had almost all the discussions

[Trooper2]

Originally Posted by Jolly Roger bus 223

thats the easiest but you can get a 2-3 adapter plate and a few more issues to make them work.
and if i remember right the torque converter will still work but there is something extra with the flywheel because of the spacer and i might have those two backwards.
havent done that swap yet but have researched it a few years ago.
and i might have vehicles mixed up because i am in the middle helping my son build and swap a dt 360 into his f250 with a ford tranny.
if your not following it check out a tranny problem thread from mountain knome.
him and caddilac have already had almost all the discussions

I am digging into caddilac's thread now ! thanks for the info.

[cadillackid]

Originally Posted by Jolly Roger bus 223

thats the easiest but you can get a 2-3 adapter plate and a few more issues to make them work.
and if i remember right the torque converter will still work but there is something extra with the flywheel because of the spacer and i might have those two backwards.
havent done that swap yet but have researched it a few years ago.
and i might have vehicles mixed up because i am in the middle helping my son build and swap a dt 360 into his f250 with a ford tranny.
if your not following it check out a tranny problem thread from mountain knome.
him and caddilac have already had almost all the discussions

physically from a 545 to an SAE3 1000 / 2000 that came out of said SAE3 application the trans will bolt right up.. converter wise you want something in a simlar RPM range. . ie you dont want a gasoline chevy or high rev diesel converter to put on a 12V but if you ended up with 1000/2000 that came off another truck diesel.. DT466,T444E,5.9 24 valve, CAT3126 and the like you will have the right RPM range in the stall speed..



now if you are trying to roll your own by buying an SAE3 bellhousing from one place and swapping it onto a GMC trans, etc then there are likely things that may not mate up..



the SAE3 1000 / 2000s that ive seen all have the same converter offset and bolt pattern as a 545.. of course its like any trans swap you need to clearance out your converter.. on mine it fit perfect with 1/4 inch (little less) of clearance so it pulled in nicely and still made good pump engagement..



the controls and such need to match the application.. dont expect a GMC duramaxx TCM to work in a custom app .. you'll want a TCM programmed for the RPM your engine runs.. for instance if your max RPM on the 5.9 is 2600 you want as close to a 2600 RPM shift calibration as you can find.. and with a 12 valve like mentioned you'll need an external throttle box as there is no ECM to send data to the trans..

[Trooper2]

Originally Posted by cadillackid

physically from a 545 to an SAE3 1000 / 2000 that came out of said SAE3 application the trans will bolt right up.. converter wise you want something in a simlar RPM range. . ie you dont want a gasoline chevy or high rev diesel converter to put on a 12V but if you ended up with 1000/2000 that came off another truck diesel.. DT466,T444E,5.9 24 valve, CAT3126 and the like you will have the right RPM range in the stall speed..



now if you are trying to roll your own by buying an SAE3 bellhousing from one place and swapping it onto a GMC trans, etc then there are likely things that may not mate up..



the SAE3 1000 / 2000s that ive seen all have the same converter offset and bolt pattern as a 545.. of course its like any trans swap you need to clearance out your converter.. on mine it fit perfect with 1/4 inch (little less) of clearance so it pulled in nicely and still made good pump engagement..



the controls and such need to match the application.. dont expect a GMC duramaxx TCM to work in a custom app .. you'll want a TCM programmed for the RPM your engine runs.. for instance if your max RPM on the 5.9 is 2600 you want as close to a 2600 RPM shift calibration as you can find.. and with a 12 valve like mentioned you'll need an external throttle box as there is no ECM to send data to the trans..

Thanks for condensing all the info, and confirming what I was thinking. Now to start chasing down the parts!