86 5.0 Auto Rearend Question

[Wildstanger86]

I have an 86 5.0 automatic and am trying to find out what rear is in it. The axle tag is 3SL27A886F03 and what does this mean. I think it has 3.27 gear and looking at putting 3.73. Will I notice a difference by doing this?

 

[mikestang63]

yes you will notice a difference in acceleration
at 60 mph your tach will be about 300 rpm higher
You will need to buy a different speedo gear to compensate and keep your speedometer somewhat accurate- LMRS and Steeda have the calculator and correct speedo gear.
your AOD will also shift sooner in the powerband and the TV cable will need to be adjusted or an aftermarket valve body
I would also buy the largest plate trans cooler you can fit in front of the radiator

 

[Mustang5L5]

3.27 Limited slip 8.8.....assuming nobody changed them out.

And yes, 3.73s will give you a boost at the sacrifice of top end. Not very gear choice for an AOD driven on the street.

 

[Nutty 5.o]

Fwiw, I drove my 89 daily for 2-3 years with 4.10's and AOD. 3.73's would be good IMHO. But to be fair, it did have a mild built trans and converter. If you like the extra gear and sacrifice mileage, 4.10's. I drove it gentle and preferred the shifting early.

 

[Wildstanger86]

How do you adjust the tv cable if I put in the 3.73.

 

[Wildstanger86]

Fwiw, I drove my 89 daily for 2-3 years with 4.10's and AOD. 3.73's would be good IMHO. But to be fair, it did have a mild built trans and converter. If you like the extra gear and sacrifice mileage, 4.10's. I drove it gentle and preferred the shifting early.

Did you adjust your tv cable when you put the gears in?

 

[Nutty 5.o]

Did you adjust your tv cable when you put the gears in?

Yes I did. Always a good idea and checked mine regularly.

 

[Wildstanger86]

is there a special gauge that you need to set it and where do u get it.

 

[Nutty 5.o]

is there a special gauge that you need to set it and where do u get it.

EDIT: Apparently there's a better way using a gauge so recommend following that procedure:

There's no tool that I used but I would get the brass/bronze bushing and clip to replace the the rubber bushing. I followed this procedure and it had held up fine for the 2-3 years I drove it every day 50-60 miles and the new owner until he passed away drove it regularly with a SC trim on it.

http://www.txchange.com/aodadj.htm

I'm 99% sure you would have the block setup to follow above.


View: https://www.youtube.com/watch?v=6L3hNzxdiYw