Question about rear ends

cantcatchme

Registered User
What would the best rear end be for my 89 5-spd?? I heard a rumor that swapping a rear end from an auto would be perfect for a 5spd, any truth to this??

Danny
 
If the AOD car has a 3.27 rear end like my 35th does then it would be a good swap. Your 5spd has a 2.73 and that is a significant difference. You won't lose too much mpg either.
 
Just what I wanted to hear

That's just what i wanted to hear:D !! now, is this an easy swap. is there any modification involved?

Thanks
Danny
 
I get my friend Otis to do it for me. I watched him once, he pulls the axles out, disconnects the U-joint for the driveshaft, unbolts the original, and bolts the new one in and reinserts the axles and U-joint. A Mark VIII has an aluminum housing but I'm not sure what the ratio is. It might be a 3.08.
 
Rear ends

Are the 3.27's the BEST for my 5 spd, or is there a better ratio for it? I'm trying for optimum performance for a 400 hp motor (give or take 20 hp) and I want to make sure I have the best rear gears to put that power to the floor. Also my other sc is a 91 auto, any idea what gear ratio is in that rear?
 
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For the street 3.27's are best overall for a 5 spd. 3.55's are almost too short as you can't much speed out of 1st before you have to shift, but they are fine for the 1/4 mi dragstrip.
 
Check the tag in the drivers side door jamb under AX. E = 3.27 Trac-Lok, 5=3.27 Standard, Z=3.08 Trac-Lok, and Y= 3.08 standard
 
wooow

That's just what i wanted to hear !! now, is this an easy swap. is there any modification involved?


OK i just swaped my 3:27 to 3:73 and it was no Easy swap buddy good luck:::confused:
 
Its a real easy swap unless your a (edit - derogatory personal comments). Just take out your pumpkin with the old gears in it, then take that and your new gears to a shop, have them put in the ring/pinion, then take home the pumpkin and re-install it
 
mn12sc35th said:
Check the tag in the drivers side door jamb under AX. E = 3.27 Trac-Lok, 5=3.27 Standard, Z=3.08 Trac-Lok, and Y= 3.08 standard

Very helpful info! Is there any listing or guide for which year models, motors, etc had a specific rear end ?
 
The original pumpkins also have a metal tag on one of the upper cover bolts with the gear ratio. You see something like "3L27 for a locking 3.27 rear.

For the most part all the 5-speed SCs had the 2.73s with traction lok, the 89-93 AOD had the 3.27s with traction lok and the 94-95s 4R70Ws had 3.27s or 3.31s, but were an open diff. Not sure on the Mark VIII gear ratios (probably 3.27s or 3.31s), but all were open diffs.
 
I went from 2.75's to 4.10s in my mustang,with an aod. IT is the best thing I ever did.. shifting into 2nd at 60mph with the 2.75's was terrible... witht the 4.10s it shifts at 35mph, and lightes them up very nicely.. and on the highway im running 2500rpm at 70.

milage droped about 1-2mpg.. I still get 24..
 
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