Standard to automatic changeover

Raymond smith · March 21, 2021, 01:42:16 PM

Want to change from standard to automatic in 1989 102C3. Donor bus is 1976 MC8. 740 allison with cable operated shifter. What parts will i need to find to do this. My engine is 6v92. Donor bus is 8v71. Will the flexplate fit my engine. Thanks in advance for any help. Raymond

luvrbus · March 21, 2021, 02:34:48 PM

The flex plate itself will work but you need to change the center hub,your bell housing may or may not work some MCI bell housing are not deep enough for a 740 because the starter ring gear on the 740 is on the torque converter

Raymond smith · March 21, 2021, 02:44:15 PM

Is that the sae 1&2 bell housings i have read about. No sure what you mean by the center hub. Will the bellhousing off the 71 fit the 92. Basically what im asking, besides the 740 and shifter will anything else work. If it is a big job I will just change my clutch. Thank you Raymond

TomC · March 22, 2021, 07:54:07 PM

Don't worry about whether it is a big job or not, the rewards of having an Allison automatic over just a 4 speed manual are big. The performance, ease of driving, backing up is fantastic. Yes your fuel mileage will take a hit, but the performance factor is second to none. Good Luck, TomC

freds · March 23, 2021, 01:59:55 PM

Quote from: TomC on March 22, 2021, 07:54:07 PM
Don't worry about whether it is a big job or not, the rewards of having an Allison automatic over just a 4 speed manual are big. The performance, ease of driving, backing up is fantastic. Yes your fuel mileage will take a hit, but the performance factor is second to none. Good Luck, TomC

Plus you might be able to convince a lady friend to do some of the interstate driving...

dtcerrato · March 23, 2021, 03:03:30 PM

Mine does but won't shift it. She takes the wheel for hours on the open hwy. - thankfully we have power assist steering...

usbusin · March 23, 2021, 04:19:54 PM

I don't want to incriminate you, but do you change drivers on-the-fly? In my 4104 on a cross country trip my boys and I would change drivers that way. Real easy in the 4104, just stand up and steer and the other driver slide in underneath you. Texas, Kansas, Nebraska real straight and flat. Many, many years ago.

ol713 · March 23, 2021, 04:27:09 PM

Quote from: usbusin on March 23, 2021, 04:19:54 PM
I don't want to incriminate you, but do you change drivers on-the-fly? In my 4104 on a cross country trip my boys and I would change drivers that way. Real easy in the 4104, just stand up and steer and the other driver slide in underneath you. Texas, Kansas, Nebraska real straight and flat. Many, many years ago.

That's the way I have done it!! Many years ago.

Merle

chessie4905 · March 23, 2021, 04:44:35 PM

Wife and sil drove my 1948 Brill. They really had to hang on the wheel to steer on the off ramps. Manual steering. Only interstate driving without crazy traffic.

dtcerrato · March 23, 2021, 06:24:00 PM

Changing drivers on the fly is a cinch with throttle lock...

TomC · March 23, 2021, 06:54:33 PM

Exactly why I took out the 13spd Roadranger manual transmission and had an Allison HT740 installed. Even though I lost the overdrive, the 11R-24.5 and 3.55 rear end ratio will still give me 1830rpm at 65mph with a 2,200rpm top speed of 78mph-plenty fast. And after 1.3 million miles of driving a 13 speed, I have nothing to prove. Good Luck, TomC

Raymond smith · March 28, 2021, 07:24:49 PM

Thanks to all that answered. I was hoping to aquire all the needed parts before I commit to the change over. I will have to find someone who knows about the different bellhousings Cheers. Raymond

luvrbus · March 29, 2021, 03:48:13 AM

Quote from: Raymond smith on March 28, 2021, 07:24:49 PM
Thanks to all that answered. I was hoping to aquire all the needed parts before I commit to the change over. I will have to find someone who knows about the different bellhousings Cheers. Raymond

Your bus will have the SAE 1 bellhousing ,if you look above the starter there is a plug if your bellhousing has that plug a 740 will work if not start looking for another bellhousing

Raymond smith · March 29, 2021, 03:10:47 PM

Thank you Luvrbus for your reply. I have a 1-1/4" threaded hole above my starter, no plug in it. We should be good to go then,just have to find the center for the flexplate also do you think the driveshaft will work. Thanks again. Raymond

Utahclaimjumper · March 29, 2021, 03:30:33 PM

You almost always have to have the drive shaft shortened,, it varies with bus model. When doing my 4106 I ended up with 17 inches,, it makes alignment very important..>>>Dan