Using 7:5 rear / stock AOD with HO motor on '88 Tbird ?

gary3072

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Dec 7, 2018
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Im currently doing a motor swap in my 88 Thunderbird Sport for a 1990 HO Mustang motor but keeping the stock 7:5 rear and AOD. Will this setup be sufficient with the increased motor power ? Also swapping stock 2:73 gears for 3:45's...

Any help or info would be greatly appreciated...

Thanks!
 

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7991LXnSHO

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Sep 1, 2010
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If the stock rear has an open differential, you do not use slicks, and driv In an enthusiastic, but not on an abusive manner, the rear end will be fine for a long time, and you will have time to save up for a better AOD. Now if do the shift shuffle to keep it in second, and do not have any valve body upgrades, the transmission will start to act goofy soon.
I put a Ford clutch type Limited slip in the 7.5 rear in my 79 5.0. Street tires and the SROD were the leak links. So the 7.5” rear stood up to moderate abuse, a lot of daily driving and an E7 roller motor and Edelbrock intake swap.
 

Rcdgl

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Feb 19, 2018
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I have a 7.5 in with a Ford Performance or whatever it was called traction lock and 4.10 gears that I bought new and installed. Its in an 82 hatch with a carbed 302. Its been 7.80 in the eighth, with 1.8 sixty foots on drag radials. Seems fine.
 

7991LXnSHO

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Sep 1, 2010
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@Rcdgl how many trips, how long and what type of transmission in this car?

I have a 7.5 in with a Ford Performance or whatever it was called traction lock and 4.10 gears that I bought new and installed. Its in an 82 hatch with a carbed 302. Its been 7.80 in the eighth, with 1.8 sixty foots on drag radials. Seems fine.
 

gary3072

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It's a stock 4 speed AOD....1988. Rarely take long trips in it aside from work...82k on it. Longest trip i ever took in it was from Missouri to Connecticut
 

CarMichael Angelo

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Power doesn't kill a rear end. Abuse does. Putting a set of drag radials, or slicks on the car will most certainly cause that thing to fail. If a 7.5 diff was up to the task of handling 300 ft lbs of torque, there was never any reason for Ford to upgrade it to an 8.8.
If you street drive the car on street tires, and you don't act a fool, the rear will probably never give you any trouble. Travel Distance will not affect it at all.

Conversely, if you do ever plan to drag race the car on any tire better than a street tire, you are setting yourself up for failure. It may, or may not happen immediately, but don't kid yourself.
 

gary3072

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Dec 7, 2018
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Power doesn't kill a rear end. Abuse does. Putting a set of drag radials, or slicks on the car will most certainly cause that thing to fail. If a 7.5 diff was up to the task of handling 300 ft lbs of torque, there was never any reason for Ford to upgrade it to an 8.8.
If you street drive the car on street tires, and you don't act a fool, the rear will probably never give you any trouble. Travel Distance will not affect it at all.

Conversely, if you do ever plan to drag race the car on any tire better than a street tire, you are setting yourself up for failure. It may, or may not happen immediately, but don't kid yourself.
Thanks for the helpful info...no, i have no plans of racing the car. Maybe just a little fun with burnouts now and then lol. My big concern is the transmission being 30 years old and stock....it still works great but with the added HO power i hope it keeps up. I am adding an aod cooler to it as well. Ive also kept Lucas treatment mixed in with the type F fluid
 

CarMichael Angelo

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That does not sound nearly as fragile as many here think.
Yeah I guess..you can also ride a mtn bike along the spine of a really, really treacherous mtn. and survive too.

There are videos of guys doing it..everybody should be able to do that then.......right?