Twin stick AOD problem

[ngsd]

I am finishing up a project with a new engine and AOD with a D20 all rebuilt. Just got it going and the D20 feels like it is only in rear low. I can't get it to find high in either front or rear. Could the input gear be on backwards or any idea?

 

[Broncobowsher]

Does the shifter go into gear? Or the shifter doesn't move into position? Might be fighting the interlock pills.

Input gear on backwards you will get the shifter going into gear but will have no high power to the rear, but you will front.

 

[ngsd]

The rear goes into gear but the high position puts it in low

 

[JB Fab]

Rear output sliding gear backwards?
Open the PTO cover and take a picture?

 

[Broncobowsher]

The rear goes into gear but the high position puts it in low

That makes no sense to me. I don't see how high could be low. When the shift shaft is pushed in, and the shifter is a lever so that is forward, that can only be low range.
Pull the shifter back, pulls the shift shaft out of the case, can only be high range.

 

[ngsd]

it makes no sense to me either. The high position is in low, the neutral position is still in low and I cant get it into a high position as that goes into neutral.

 

[ngsd]

Rear output sliding gear backwards?
Open the PTO cover and take a picture?

is that possible? I will drop the cover and take a pic if so.

 

[ngsd]

I was able to pop the cover today. It definitely does not engage the gears and is way off but not being familiar with these I cant tell was is correct.

 

[Broncobowsher]

You somehow put the rear selector gear in backwards. I didn't know that was even possible. The gear needs to be flipped. The straight cut gears go in the middle, not up against the rear output.

FYI, the input gear. The helical one that goes on the spud shaft. That is the one that is typically installed backwards. When that happens you don't gear high output to the rear. The selector gear has no teeth to mesh with. In this case you are getting the low range to engage when it should be mating for a direct connection.

What you have done is a new one to me. And I thought I had seen it all by now.

 

[ngsd]

Thanks I was totally confused by what I saw too. I have never built one so I was just going off Youtube for verification of what I was looking at. It was built and installed before I bought it and just got it running. I have have no idea who built it. Out it comes! Thanks

 

[ngsd]

Here is a better pic of it, now you really can say you have seen it all!

 

[mpboxer]

Love this forum. Such a knowledge group of individuals! Glad it's figured out Nick.

 

[ngsd]

You somehow put the rear selector gear in backwards. I didn't know that was even possible. The gear needs to be flipped. The straight cut gears go in the middle, not up against the rear output.

FYI, the input gear. The helical one that goes on the spud shaft. That is the one that is typically installed backwards. When that happens you don't gear high output to the rear. The selector gear has no teeth to mesh with. In this case you are getting the low range to engage when it should be mating for a direct connection.

What you have done is a new one to me. And I thought I had seen it all by now.

Since I have never torn into one, I was watching the videos but only have found full rebuild. How far down do I have to disassemble to get that gear out to turn it around? Thanks I appreciate all the responses.

 

[Broncobowsher]

Since I have never torn into one, I was watching the videos but only have found full rebuild. How far down do I have to disassemble to get that gear out to turn it around? Thanks I appreciate all the responses.

Short answer, don't know.

Transfer case has to come out. Shift fork needs to be removed. Rear output probably needs removed (I would count on it). Maybe the middle shaft. Front output can probably stay.

It has been 15 years since I was last in one. And I wasn't trying to take it half apart, I was going full in on it.

 

[ngsd]

Thanks, well I just wanted to get this thing going but I guess it is a good opportunity to finally learn how do do one. Thanks everyone this is a great group.

 

[ngsd]

Not sure why I was so concerned, watched a few videos and it was pretty easy. Now i will put it back in and see if I messed anything up! I did get to weld up a stand for the trans jack to lift the TC back in, been wanting to do that for a while anyway.

 

[ngsd]

Well that excitement was short lived. It worked and went back in fine but now that I can drive at speed it has a vibration under acceleration. May be a driveshaft issue but hope it is not the TC. I have not driven it until now so I dont have any reference as these are all new parts.

 

[Broncobowsher]

That sounds like rear driveshaft vibration from axle wind up. The pinion climbs under load and the U-joint vibrates. Have a GoPro? Aim it at the pinion U-joint and go drive it. See what the loaded angle looks like.

 

[ngsd]

That sounds like rear driveshaft vibration from axle wind up. The pinion climbs under load and the U-joint vibrates. Have a GoPro? Aim it at the pinion U-joint and go drive it. See what the loaded angle looks like.

Thanks, I assumed it was driveshaft and the carden seemed rather stiff. I swapped out the the shaft from my other one just to eliminate that possibility and it feels great. So that was the issue. I will now try this shaft back in the other rig since it has 2" less lift and see if it feels better there. Thanks as usual for your quick response.

 

[ngsd]

Rear output sliding gear backwards?
Open the PTO cover and take a picture?

You were spot on with that one. Easy fix and working great with your new Twin stick shifter in it!