Allison v730

Winging it · April 28, 2021, 04:58:03 PM

Hi all, transmission failed. We bought a used one and put it in, it does not work at all. I have another that was rebuilt 20 years ago and never installed, it is a V730d. I will swap the tail and the valve body. I am putting it in a 1969 pd4107, with an 8v71. Do I need to worry about the rotation of the transmission? I am pretty sure the bus is LH rotation.

luvrbus · April 28, 2021, 05:26:30 PM

Your engine is left turning post the model number and some one here can tell you here if it is a right hand V730,I doubt you have one though they were only found in the RTS with the 6v92TA and series 50 engines

chessie4905 · April 28, 2021, 08:16:09 PM

Right hand v730-v731r or rh, has about an additional 3 to 4 inch extension on the input side which contains reverser gearing.

chessie4905 · April 28, 2021, 08:19:00 PM

what system do you have to select n,r,d 1,2,etc? A shift lever or a push button keypad?

Winging it · April 29, 2021, 05:06:52 AM

Hi, the tag says

Winging it · April 29, 2021, 05:11:27 AM

Today I will swap the valve body and tail housing. It's there anything I need to know, or worry about?

luvrbus · April 29, 2021, 05:21:01 AM

Do you have gaskets ? why the valve body change

Bill Gerrie · April 29, 2021, 05:40:02 AM

Like luvrbus says "why the valve body". I have changed the valve body several times and it is easy but about 40 bolts. I was always able to reuse the gasket without any problems if it comes off in one piece which it probably will.

Winging it · April 29, 2021, 05:43:30 AM

Thank you. Do you know if the trail housing will swap in one piece?

Bill Gerrie · April 29, 2021, 05:45:45 AM

The tail housing will swap out very easily. I assume you have a different one with speedo take off etc.

Winging it · April 29, 2021, 05:48:50 AM

Yes, the one I am taking off has a two wire governor. I need to put on the shaft with the regular governor.

luvrbus · April 29, 2021, 06:07:44 AM

You do know any Allison dealer can Dyno the transmission and then you will know if the transmission is good or not and they can set the shift points before installing it, still trying to figure out why you are changing the valve body

Winging it · April 29, 2021, 06:15:14 AM

The valve body on this one is different. The shift selector tab it's not on this one. It also had a plug in for electric. It looks like some kind of 730-731 hybrid conversion that I an reversing. I hope this makes sense. I can post a picture of the two side by side, In about a half hour.

Bill Gerrie · April 29, 2021, 06:18:15 AM

My post didn't post so here it is again.
I found the easiest way to remove the rear housing is to use a floor crane and stand the trans with the rear housing straight up. You will need a gasket for this one or you can make one from a sheet of gasket material. The housing isn't very heavy so no need for a crane to lift. I assume you have the V730 manual which shows the inside of the trans.

Bill Gerrie · April 29, 2021, 06:20:33 AM

Sounds like you have a V731 which is identical inside except for the valve body. I have switched the 730 and 731 valve bodies with no issues. Just make sure you put all the bolts back in the proper holes.