VS2-8 transmission help

[tanman496]

My name is Mark, I bought a 1980 GMC  H8H649 about a month ago, The bus came with a manual transmission from GM someone installed a VS2-8 automatic transmission which is fine but , you have to shut the bus off to change gears from forward to revease. After looking high and low on the net noone seems to have a wiring diagram for the H8H649. I have one for a 1978 4905a bus but it dont show one with the VS2-8 trans as a option. can anyone help me wire this up , what parts will I need and where can I get them?? Thanks alot for reading Mark

[tanman496]

My name is Mark, I bought a 1980 GMC  H8H649 about a month ago, The bus came with a manual transmission from GM someone installed a VS2-8 automatic transmission which is fine but , you have to shut the bus off to change gears from forward to revease. After looking high and low on the net noone seems to have a wiring diagram for the H8H649. I have one for a 1978 4905a bus but it dont show one with the VS2-8 trans as a option. can anyone help me wire this up , what parts will I need and where can I get them?? Thanks alot for reading Mark

[Scott Crosby]

Why do you have to turn it off to switch from f-r?  Is it because it grinds and does not want to go into gear?  Has someone bypassed the neutral safety and you have to start it in gear? 

[Scott Crosby]

http://brandon314.wordpress.com/2011/08/12/vh-vs-series-service-manual/

[tanman496]

Yes it does grind when you try to put into gear. And yes it will start in any gear so I guess the neutral safety switch is disconnected

[Scott Crosby]

That is a common problem.  The neutral safety switch is a great work around.  I have a similar trans the VH9, you have the better looking sister trans to mine.  I start in gear to avoid the grinding.  I can switch gears from F to R once the fluid is warmed up.  But I have to do it fast.  Out and into the other gear really fast.  I've never heard of a fix for the problem other than the workaround which you already have. Loren joplin said it had something to do with a hanging clutch pack that was a GM change up that had that negative result.  I don't know about that, I was also told that it might be a few other things too.  Just don't grind the gears, if it happens stop it right away.   

If you find a fix, let me know....  I've asked, otherwise it's not to bad to live with it.  I avoid parking where I have to put it into reverse, and mostly just leave it in F 

[pabusnut]

I had a VS2-8 in my 5301 and had the same trouble.  I always started it in neutral until I had good air pressure.  Then I shut down-put in Forward, and restarted.  I could switch from F to R and back again if I did it quickly once the fluid was warmed up. 

It was never a problem for me, and some days I wish I had the Automatic in my 4905, especially when trying to back in a campsite and not slip the wet clutch!

Steve Toomey
PAbusnut

[tanman496]

well someone installed this transmission but never installed all the parts that go with it , like a shift switch and all the wiring that has to be hooked up so you have backup lights. Its a real pain to have to shut it off to change gears when your trying to turn the bus around.

[Scott Crosby]

My bus a 61 GMC didn't come with back up lights or any wiring for them.  I added them myself. 

[buswarrior]

tanman, you might want to look up Bill Gerrie over at BNO.

He knows an awful lot about these transmissions and might have a few ideas for you.

happy coaching!
buswarrior

[tanman496]

Thanks Bus warrior I never heard of BNO Who are they?? do you have a number for them?

[thomasinnv]

Thanks Bus warrior I never heard of BNO Who are they?? do you have a number for them?

BNO is "the other board"


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[luvrbus]

BNO, Bus Nuts On Line a forum like this almost the same they have some great GM people there

good luck

[RJ]

www.busnut.com

Click on the "BNO BBS" link in the LH column.

FWIW & HTH. . .