In my 1972 bus I changed out the stock engine and transmission for a 2 litre engine and an 091 transmission. After the swap I did a road test and discovered I only had 1st and 3rd gears. So I loosened the shift rod base, moved it forward as far as it would go and still no 2nd, 4th or reverse. Next I disconnected the flexible coupling from the tranny shaft and measured the distance it would pull out from the tranny. I also compared that distance with the distance my 72 tranny shaft would pull out; both measured approximately one inch so the tranny should have all gears. Then with the bus on jack stands I left the shift rod disconnected and pulled on the tranny shaft. Crawled out from under the bus, started the bus, and I had tire rotation. I did this several more times and no matter how far out or in the shaft was, I had tire rotation which to me means I have all gears but I just can't get all of them to engage.
It feels like I'm not getting the full travel that I need on the shift rod so that 2nd, 4th and reverse engage. Is the 091 slightly longer than the 72 tranny? Has anyone else made this tranny swap and if so, if you ran into this problem, what did you do to fix it. Thanks in advance, Gunthner.
tranny swap issues
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Re: tranny swap issues
The shift couple is probably not clearing the cross member in front of the tranny. You can either cut, grind, or bend to get it to work.
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Re: tranny swap issues
Wildthing, I will crawl under the bus again and do some research. I believe however that when my buddy positioned the shifter into second gear there was still room for the shift coupler to move forward (I was under the bus watching while he did this). I believe the gear shift lever simply was maxed out but the gears weren't engaging. You have however given me another idea.
Let's say that the coupler won't move any further than it does right now but it still has clearance. If I disconnect the gear shift from the shifter shaft and then pull on it, and then if it engages so that I have 2nd or 4th gear, I'm back to where I started. That would lead me to thinking that the engine and tranny need to be moved rearward a 1/4 to 1/2 inch so it will work.
I will get back to you on this as I can see that many have read the posting but you were the only person that suggested anything. Appreciate it.
Let's say that the coupler won't move any further than it does right now but it still has clearance. If I disconnect the gear shift from the shifter shaft and then pull on it, and then if it engages so that I have 2nd or 4th gear, I'm back to where I started. That would lead me to thinking that the engine and tranny need to be moved rearward a 1/4 to 1/2 inch so it will work.
I will get back to you on this as I can see that many have read the posting but you were the only person that suggested anything. Appreciate it.
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- Joined: Thu Jun 03, 2004 12:42 am
Re: tranny swap issues
The shift rod is a little longer in an earlier bus than a later one. Maybe this is part of your problem as well.
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- Posts: 98
- Joined: Sat Nov 16, 2002 12:01 am
Re: tranny swap issues
Wildthings, you were right on about rear shift rods being ever so slightly different lengths.
I crawled under the bus and disconnected the coupler that holds together the front and rear shifts rods. I then pulled on the rear shift rod engaging probably 2nd gear. Started the bus and the tires did spin. Just to be safe I pushed on the rear shift rod and engaged first. Started the bus and again, the tires would spin. Then I pulled out on the rear shift rod again, engaged 2nd gear and sure enough, the holes that the coupler screws through and holds the rods together, do not line up when the tranny is in second (or fourth) gear. You can see both holes but one is about 1/4" inch off from lining up.
I looked around and have thought abour various scenerios on where I can make adjustments to accomodate for the 1/4" difference, and for the life of me, there aren't any. I'm guessing that all front rods for all Bay years are the same and I have to fine another later year rear shift rod. Either that or go to a machine shop and have them drill a hole 1/4" closer toward the rear and on the other side of my current rear shift rod.
I crawled under the bus and disconnected the coupler that holds together the front and rear shifts rods. I then pulled on the rear shift rod engaging probably 2nd gear. Started the bus and the tires did spin. Just to be safe I pushed on the rear shift rod and engaged first. Started the bus and again, the tires would spin. Then I pulled out on the rear shift rod again, engaged 2nd gear and sure enough, the holes that the coupler screws through and holds the rods together, do not line up when the tranny is in second (or fourth) gear. You can see both holes but one is about 1/4" inch off from lining up.
I looked around and have thought abour various scenerios on where I can make adjustments to accomodate for the 1/4" difference, and for the life of me, there aren't any. I'm guessing that all front rods for all Bay years are the same and I have to fine another later year rear shift rod. Either that or go to a machine shop and have them drill a hole 1/4" closer toward the rear and on the other side of my current rear shift rod.
- fusername
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- Joined: Sun Jan 28, 2007 11:26 am
Re: tranny swap issues
I would suggest just making your own notch in the rod in the rod, since you need to drop engine/trans to pull the rear rod to replace it. instead pull just the front one and put the divit in where needed, screw it all back together and see if it works. if that doesn't fix it, or its too hard to drill, you could always tack weld it together, then use a set screw for insurance.
give a man a watch and he'll allways know what time it is. give him two and he can never be sure again.
Things are rarely just crazy enough to work, but they're frequently just crazy enough to fail hilariously.
Things are rarely just crazy enough to work, but they're frequently just crazy enough to fail hilariously.