AOD to 4r70w swap in an 86 Bronco

[Nickelplate]

I doubt you'll get your core fee back. And I'd be surprised if they don't send it to collections. But you are prepared for that, although you may have to get an attorney even then.

Good luck! http://www.garysgaragemahal.com/uploads/6/5/8/7/65879365/crossed-fingers-20-pixel_orig.png

I got a question about the shift linkage that I grafted together.

Here's the AOD arm. I took the whole assembly out and cut the shaft off of it so that I retained the metal circle there at the top. That way I could tell where the center was to compare it with the 4r70w one.

This is the the 4r70w arm. Instead of a hole at both ends, it has that weird pin, so I had to cut and weld.

Here's the right stuff! It's just tacked in the picture, but that was the length and size it stayed, and it's in use now.

The dimensions I had to consider:

1. center-to-center length of the AOD arm. (Lefthand green line) It was shorter than the 4r70W one, so the whole assembly needed to be shorter

2. distance of the linkage-side eye from the transmission to where the linkage should connect. (right-hand green line)

 

[Tarheel Blue]

I got a question about the shift linkage that I grafted together.

Here's the AOD arm. I took the whole assembly out and cut the shaft off of it so that I retained the metal circle there at the top. That way I could tell where the center was to compare it with the 4r70w one.

This is the the 4r70w arm. Instead of a hole at both ends, it has that weird pin, so I had to cut and weld.

Here's the right stuff! It's just tacked in the picture, but that was the length and size it stayed, and it's in use now.

The dimensions I had to consider:

1. center-to-center length of the AOD arm. (Lefthand green line) It was shorter than the 4r70W one, so the whole assembly needed to be shorter

2. distance of the linkage-side eye from the transmission to where the linkage should connect. (right-hand green line)

Thanks Brad,

I’ve pulled some of those arms over time as seen here

I honestly don’t remember each arms original donor except that of the two that are the same, one of them was attached to the ‘95 4R70W that I’ve rebuilt. The only difference in those two is that I disengaged the pin from the one. FYI, the c/c hole dim is 2.5” and the face to face offset is 7/8”.

What I’m most interested in figuring out is which bracket I need to find to support the transmission side of the bell crank shaft.

I pulled this off of an ‘85 F159 w/ 4.9 and an automatic, but me being the idiot that I often am, I forgot to identify which auto it was. I have to imagine that it was either an AOD or a C6.

And this is the bracket that was attached to the 4R70W and is used to secure the shift cable.

I’m trying to decide if I want to use the 80-86 bell crank connection between the steering column and the tranny or the newer cable system.

[Tarheel Blue]

Thanks Brad,

I’ve pulled some of those arms over time as seen here

I honestly don’t remember each arms original donor except that of the two that are the same, one of them was attached to the ‘95 4R70W that I’ve rebuilt. The only difference in those two is that I disengaged the pin from the one. FYI, the c/c hole dim is 2.5” and the face to face offset is 7/8”.

What I’m most interested in figuring out is which bracket I need to find to support the transmission side of the bell crank shaft.

I pulled this off of an ‘85 F159 w/ 4.9 and an automatic, but me being the idiot that I often am, I forgot to identify which auto it was. I have to imagine that it was either an AOD or a C6.

And this is the bracket that was attached to the 4R70W and is used to secure the shift cable.

I’m trying to decide if I want to use the 80-86 bell crank connection between the steering column and the tranny or the newer cable system.

Oops!

I guess I got too excited to hit that “ post message” button, I should have continued to say that this bracket

does not marry well with my tranny. Only one of the two attachment points lines up and the pivot point grommet would end up being located in the wrong spot for the bell crack rod. I guess in came off of a C6 as the AOD and 4R70W cases are very similar. So I’m looking for help as to which bracket you used to attach your bell crank to your tranny.

 

[mat in tn]

Oops!

I guess I got too excited to hit that “ post message” button, I should have continued to say that this bracket

does not marry well with my tranny. Only one of the two attachment points lines up and the pivot point grommet would end up being located in the wrong spot for the bell crack rod. I guess in came off of a C6 as the AOD and 4R70W cases are very similar. So I’m looking for help as to which bracket you used to attach your bell crank to your tranny.

pretty sure this older bracket is for c6. one of the points that I look at which I have not heard you mention is each transmission has its own "range of throw" of the lever. this must match the range of throw of the shifter and the transfer bar assembly. I am doing the same thing right now and have three different transfer assemblies that have different length levers. if this does not get correct then the trans may not go to park or first gear following the shifter.

[Rembrant]

I got a question about the shift linkage that I grafted together.

Here's the AOD arm. I took the whole assembly out and cut the shaft off of it so that I retained the metal circle there at the top. That way I could tell where the center was to compare it with the 4r70w one.

This is the the 4r70w arm. Instead of a hole at both ends, it has that weird pin, so I had to cut and weld.

Here's the right stuff! It's just tacked in the picture, but that was the length and size it stayed, and it's in use now.

The dimensions I had to consider:

1. center-to-center length of the AOD arm. (Lefthand green line) It was shorter than the 4r70W one, so the whole assembly needed to be shorter

2. distance of the linkage-side eye from the transmission to where the linkage should connect. (right-hand green line)

I remember going through all of this. My 4R70W is from a 2wd 1996 F150 and I too cut the original shift lever and welded a new end on it. I’m using an aftermarket B&M shifter that has its own detent positions so I had to match it perfectly. I made a bracket for the cable end and modified the shift lever to fit copying pictures from the instructions. Luckily for me it seems to have worked fine on the first try:)

[Nickelplate]

pretty sure this older bracket is for c6. one of the points that I look at which I have not heard you mention is each transmission has its own "range of throw" of the lever. this must match the range of throw of the shifter and the transfer bar assembly. I am doing the same thing right now and have three different transfer assemblies that have different length levers. if this does not get correct then the trans may not go to park or first gear following the shifter.

Hey, Mat! The "throw" is the lefthand green line on my drawing. the 4r70w lever was slightly longer than the AOD one, so I had to make sure to keep the AOD length, since the attached lever on the column shift apparatus did not change.

Luckily the detents in the column and the shift positions in the 4r70w line up. I take this to mean that the detents in the AOD and in the 4r70w are the same.

the problem I have right now is the clocking. If the default AOD clocking is 8 o'clock, then the 4r70w is at 6. Luckily the column shifter has some adjustment to it. Unfortunately, that makes the column side of the linkage max out before it can swing the trans-side arm to the 1st gear position. The truck was sitting outside and it was raining today, so I couldn't get the pictures I wanted. But when I can get under there without getting muddy, I'll take pics to explain what I mean.

The solutions are either to lengthen the rod between the two arms so that the column side doesn't max out before the trans side. Or I could cut and reclock the trans-side arm to closely match the original AOD angle. I think the rod will be cheaper.

[Nickelplate]

Hey, Mat! The "throw" is the lefthand green line on my drawing. the 4r70w lever was slightly longer than the AOD one, so I had to make sure to keep the AOD length, since the attached lever on the column shift apparatus did not change.

Luckily the detents in the column and the shift positions in the 4r70w line up. I take this to mean that the detents in the AOD and in the 4r70w are the same.

the problem I have right now is the clocking. If the default AOD clocking is 8 o'clock, then the 4r70w is at 6. Luckily the column shifter has some adjustment to it. Unfortunately, that makes the column side of the linkage max out before it can swing the trans-side arm to the 1st gear position. The truck was sitting outside and it was raining today, so I couldn't get the pictures I wanted. But when I can get under there without getting muddy, I'll take pics to explain what I mean.

The solutions are either to lengthen the rod between the two arms so that the column side doesn't max out before the trans side. Or I could cut and reclock the trans-side arm to closely match the original AOD angle. I think the rod will be cheaper.

I was able to find someone else's pic of the linkage.

You can see how that upper arm is at the same angle as the lower arm. With mine, the lower arm and upper are at different angles. I would just cut that rod and add whatever length was needed to bring them back to the same angle again.

[Tarheel Blue]

I was able to find someone else's pic of the linkage.

You can see how that upper arm is at the same angle as the lower arm. With mine, the lower arm and upper are at different angles. I would just cut that rod and add whatever length was needed to bring them back to the same angle again.

If you notice in my picture above where I have the three shift arms that attach to the mlps, one of them has the oblong hole at a different “clocking” than the other two. Perhaps Gary or someone else that has a decoder ring can tell us in which applications those engineering numbers were used.

[Nickelplate]

If you notice in my picture above where I have the three shift arms that attach to the mlps, one of them has the oblong hole at a different “clocking” than the other two. Perhaps Gary or someone else that has a decoder ring can tell us in which applications those engineering numbers were used.

The one with the different clocking is the one for the cars that "pull" the shift lever of the transmission into gear rather than "push" like the AOD does.

[mat in tn]

The one with the different clocking is the one for the cars that "pull" the shift lever of the transmission into gear rather than "push" like the AOD does.

I went out to the garage and looked at a couple different installations last night and then laid awake sorting out design and explanations. hopefully I can clear up what I was trying to convey in regard to "range of throw". by this I'm referring to the arc of movement more in degrees as opposed to length of radius referring to the lever and its relative leverage. you are almost there with your comment on how the levers are clocked. take the mustang or t bird and the console shift. the shifter is on a horizontal plane so being clocked at 12 in the center of the range of throw provides the best leverage to operate the selector. in trucks/vans with column shift, the "cable" is mounted on a horizontal plane also and comes from the front, so the same lever is clocked at 6.

now we take this lever and put in a vehicle with a bell crank that is at a 30-degree slope and the center line of the range of throw needs to be about 7:30. if the rod is just lengthened then the center line of the range of throw is not correct. leverage is best at right angles. 90 degrees. before and after that the leverage is diminishing whether pushing or pulling. if you start at 90 in park then the bell crank may be running out of leverage before you are able to get down to 1st gear. the detent plate inside the trans has a range of throw of approx. 45 degrees. so, the lever has the same. so, splitting this, the degrees of travel for and aft will have a minimal reduction in leverage. at the point over an arc of 180 degrees of travel leverage goes from 0 (basically locked) to best at 90 then diminishing back to zero at 180. I only use the 180 example to explain the diminishing leverage.