AOD transmission crossmember

7173Mustangs.com

Help Support 7173Mustangs.com:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
May 19, 2021
Messages
1,342
Reaction score
934
Location
Fort Mohave, AZ & So Cal (Upland)
My Car
73 Grande will undergo three phase build process. Phase 1 is complete (driver). Phase 2 is interior/exterior restoration. Phase 3 is ++ performance.
While this topic may have been covered on the site, try as I may I could not find it. I’m installing a 302/AOD from a 87 TBird and wonder if the original crossmember and trans mount from my previous 351/FMX would work as is?

 
My swap about to happen, delayed by some stubborn Lincoln Explorer that refuse to let my friend's lift free.

So got plenty time to prep it: 
Mine is a 351/fmx, so basically exactly the same.
The cross member will need some rework, and the holes moved +- 2inches further back
I have seen the aftermarket supports and frankly... well lets just say, i'll adapt the original using good stuff. 

a few details you may need to think about:

- the speedometer gear should fit right into it. But you could keep the electric sensor, as there are some special adapters for the speedometer.
- you need make sure the shifter linkage is facing upwards may you want to keep the original linkage
While it's easy, make sure you do set the TV valve back into the groove and test it with the return spring before close it back.
Do change the o-rings. You will need also to pull gently the locking pen out and push it back it leveled to the casing flat surface, not deeper! Unless you want the future you be mad at past you, may you'd need reopen the trans again!
- Unless you have reinforced the middle shaft or added a ring to prevent it to bang the direct clutch and ruin that clutch by closing an oil passage ( 87 trans are with soft metal cast drums and not the steel ones of 91 and younger), I suggest you buy a lock converter. May you'd go for a non lock, add an extra cooler if you want your trans to make more than 20k miles.
- Unless you can reuse a 28 splines yoke, for t5 or c4, I bought a Sonax and I must say it was refreshing to see some real quality. Truly a nice piece and affordable too.
- Make sure you have longer bolts ready, because the AOD casing will not allow you to reuse them. Do not use the advertised ARP kit for AOD bell housing, they are 3/4 inch too short. The originals will not even reach the engine block.
- I've bought a set of waterproof connectors for the light switch and will install the other side once I know whats doing what on location. You'll need special pliers may you go that way.
- the TV cable is important for this trans so you will need a Lockar cable kit or similar, but keep in mind (in Lockar case) that you will be able to use only the cable and the return spring. The rest of their kit is total garbage and there is some fab involved if you want your cable tension to be perfectly sync with your throttle.
- you will need to fab an anchor for the tv cable that is aligned to the throttle bracket. My application being with an Holley Sniper, the bracket was already modified to go 3.5 cm sideways to be in line, so made instead a new stronger one piece bracket for both cables vs modifying again the bracket.

There are more details, but its late so I forgot :D

Hope that helps

 
Last edited by a moderator:
I’m a bit luckily in that, I’m swapping a complete eng/trans from the 87 TBird (and I’m hoping to add to my small build thread as soon as I have the motor ready to test fit), and I’m planning to use the shifter and cable from the same to make it go easier, at least one more thing I will not have to adjust. The cabling from the throttle-body has the downshift cable, and initially, I plan on leaving it where it was adjusted to (it was a driving car before the swap). I have both driveshafts, so I’ll see how integrating those go. I also have a nice Hayden cooler I found new at a thrift store.

I was wondering if I should change the converter. For the AOD, what is the primary benefit for the lockup converter? I know what one is and what it does, just wondering the benefit in this circumstances.

Does anyone know what trimming or grinding mentioned in using the original crossmember? I suspect he is referring to the mounting holes fir the transmission mount, but there were no pics or explanation. If someone could clear that up, that would be great.

 
I just reused the FMX cross member.  I'd bought a Ron Morris cross member and it fit like crap.  Wound up just notching the FMX piece, since the AOD's valve body/pan is a bit bigger than the FMX.  But to do it over again, I would've taken a little more material out of the 'flare' piece, as it's a little close to the pan (but not so much that it's an issue).

Also, I'm not sure which engine you're using, but I had to get a different flex plate for mine, going from my 351C to the '89 Mustang GT AOD I went with.  I used the '89 torque converter, and since the '89 GT also had 3.00:1 rear gears, it was a direct drop-in for me.

Here's the problematic Ron Morris cross member.  Won't fit in the standard holes for the FMX piece and wound up not level.  Can't have that.

View attachment 26899

I notched the FMX piece...

View attachment 26900

And it fits WAY better (imagine that).

View attachment 26901

This is the part of the FMX piece I would've trimmed a little better.  Not a problem... just doesn't look like it wouldn't be.

View attachment 25553

Hope that helps!

 
Wow, Mister, that the best illustration of the trans crossmember I’ve ever seen. Thanks!  I’m still wondering what the lockup converter that Fabrice recommended would do?

 
Back
Top