What Drivetrain Should I Get?

Hey all!

I'm getting a progressively worse vibration coupled with a bit of morning sickness on my '67 vert. It currently has a C-4 trans.

Now that I have to fix all this, I've decided I want to upgrade the entire drivetrain, beginning with an AOD trans, new drive shaft, and LSD. I may or may not need to replace my rear end. It's an 8" currently. Should I go 9"? If heard that is a good idea.

It is a daily driver, so I need the low RPMs at high speeds on the freeways, but I'd also like respectable off-the-start power, even though I'll never race it.

So here's the question: Beginning with a TCI AOD transmission, what else do you all recommend I get to complete the project? (brands, sizes, ratios, etc.)

I've seen a couple articles from Mustang Monthly and Mustang 360, but I wanted to get your input if possible.

Thanks in advance!
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SN Certified Technician
Apr 12, 2002
i would run an AOD, preferably the wide ratio version that some companies will build for you, and 3.50 - 3.73 rear gears. that will give you good off the line dig, with a decent cruising rpm at 65-70mph.
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I prefer to be called "Evil Genius"
Founding Member
Oct 10, 2001
Western Mass
A tip on the AOD output shaft: Make sure you get a 7 tooth output shaft vice the 8 tooth. It will make speedometer calibration that much easier!

Also; back when the 5.0 Mustangs were so popular, most of the guys with the AOD transmissions were running 3.73 or 4.10 rear gears on the street.
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Thanks again guys.

I called around, and it looks like the Mustang Shoppe here in SD has the best deal to make the conversion: $4500 out the door not including the rear end. Best price I saw by about $1000, and they specialize in Mustangs, so I know they'll do it right.

Turns out my progressively worse vibration was a slowly-deflating tire (sidewall tread hitting the pavement when I went over bumps and dips). Hardly registered any PSI! (below 20) So the rest of the driveline may be fine.

Any additional thoughts?