AOD-M Trans recommendations

I would like to hear about who I should look at for a rebuilt AOD-M (not electronic) to put into the 70 Eliminator I’m doing for a customer.
Std build 351 Clev.
Don’t want stall issues & shift kit craziness. Thanks!

Don’t buy anything from Monster. Bad product and zero support.

Thank you Royce!

And yet I put one behind a y block in a 55 tbird and it has been flawless. They modified the valve body so it shifts manually 1 2 3 and then into OD.

I hope you did not buy that transmission from Monster. They supplied a transmission to a local guy - for his '67 Cougar - it was an AOD-M and the rebuild consisted of cleaning the outside and rattle canning the transmission. When the clutches turned out to be bad my friend sent the transmission back to Monster they sent another reject for him to try. Then he tried to send that one back and got nothing.

It came from Monster. It had definitely been rebuilt and also modified to change the shift sequence. It also came with a new torque converter. It’s been in service now for about 4 years.

This is why I discourage negative comments. People have different results. Not saying Monster is great. Your experience is as good as mine. The point is that it’s not useful to use the forum to litigate the reputation of any particular company. There are people unhappy with every supplier in the automotive space. There are guys who are still mad at the engineers that designed these cars 60 years ago.

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Monster is quite deserving of Royce’s comment. The comment is right inline with the numerous customer complaints as well as the complaints and comments from transmission shops that worked on Monster transmissions. How would I know what other transmissions shops say? I’ve been in the transmission industry for 28 years and owned a shop for 19 years. Subscribe to transmission forums and groups, so I hear and see a lot about transmissions. Transmissions is a tough business and I don’t like to criticize anyone that is trying. With what I’ve seen, I’m surprised Monster is still in business. I guess their flashy advertising gets them enough new customers. I feel like it would be a disservice to other members of this site to promote the one good transmission they had and disregard all the rest.

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I am being too subtle. If you have a problem with a vendor, take it up with them. One of the very few rules is that we don’t use the forum to try to punish anybody. No matter how deserving they are of the criticism. Other wise it can rapidly turn into an ugly place. We don’t accept advertising from ANYONE so don’t go down that path. I cannot tell you how many people join the forum just so they can air their complaint about one vendor or person or what ever. I am positive that there is not one vendor that’s never made the list, and a good many of the members here that work very hard to try to help get trashed as well.

Given that I highly respect Royce and 9F91H. Both of you have contributed greatly to the forum.

I could have easily had one of those bad experiences. When we installed the transmission It was quite difficult to adjust the throttle position linkage. It was Lokar kit and the cable was binding and it even stretched a little bit. I had the gauge on the transmission and I was insisting that we do what ever it took to get it right. The owner of the car has a about 15 cars in his collection and he was saying he thought it was close enough and the shop owner wasn’t really familiar with how easy it is to blow up an AOD. Had I not stood my ground and got it dialed in properly, and locked it down to stay that way, I am sure they would have blown that thing up. Both of them thought we could just skip that step.

You definitely can’t skip proper TV adjustment on an AOD…especially with a Lokar cable. The Lokar TV cable is another kinda crappy part. Unless you plan to adapt a factory cable, Lokar is the only thing available.

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With an AOD what are the considerations for changing rear end gearing?

I’ve got 3.0 gears, and thinking an AOD would allow a higher ratio.

There are many considerations to changing the rear gearing with an AOD. You can go much higher than 3.0 gears, for example, with 4.11 gears and still have an overall final drive ratio of around 2.75 (4.11 x 0.67)

Ive found that a 3:50 is about perfect for a Cougar used like most of us do.

3.00 is about as small as you can go with OD as long as you have short tires in the rear and a stock camshaft.
3.25-3.50-3.73 is best balance in most applications.
Any bigger rear gears like 4.11 might be desired if you are trying to drag race and/or have taller tires.

IMHO a typical carburetor equiped car needs around 2000 rpm at cruise ( 70mph) to perform well. 3.50 / 3.73 seem to work well for the tire size on Cougars

I have a T-5Z in my XR-7. the old 3.00 were to tall for using the OD at anything less then 75moh. I went to 3,5 and now 76mph is just about 2K rpm. Works well for my application. I am running 255/60R 15s on the back. Smaller tires would raise the RPM at 76.

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It doesn’t seem like this thread has provided you with any answers to this question.

What are the considerations in a mechanical vs electronic AOD?

Both require crossmember mods for installation. Both require a slip yoke. May require drive shaft length change. Shift lever on trans modifications for both. Needs 2-3/4" length bell bolts.

The AOD has no electronics. Can be finicky with the TV cable adjustment. Depending on application, can be boggy going into 3rd due to direct mechanical connection. Easiest overdrive swap there is for any vehicle.

AODE and 4R70w must use a stand alone computer. Must add TPS to carb if an EFI set-up does not offer a TPS output. Other wiring and mounting TCM. Making adjustments to shift parameters in TCM can be finicky if you don’t know what to expect. Higher torque capacity than AOD. Must choose correct bellhousing for your engine. Overall, more expensive than AOD.

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