Diff Swap

Mustang Australia

Author Topic: Diff Swap  (Read 453 times)

Offline Dizzy

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Diff Swap
« on: April 08, 2021, 04:22:37 pm »
A local bloke has an 8" diff with 3.20 gears for sale @ $1,500. Said to be in excellent order and out of a 66 Mustang. My diff is also 8" but with 3.00 gears. Should I grab the one on offer, swap them and then sell mine. Looking for a little more grunt around town at the traffic light drags and don't mind a few extra rpm at hwy cruising speed. Tyres are 14/60/215f/225r

Online scollist

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Re: Diff Swap
« Reply #1 on: April 08, 2021, 04:45:43 pm »
Sounds to be expensive for an 8inch diff.

Is it an Open or LSD/Locker?  For that price I'd be hoping it is the latter - and you would want that for traffic light drags.

It also depends on how much you get for yours when you sell it. Will the price difference be worth the change from 3.0 to 3.2 ratio?

Offline Dizzy

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Re: Diff Swap
« Reply #2 on: April 08, 2021, 05:13:11 pm »
I will check if its open/LSD - mine is open

Online GEOFF289

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Re: Diff Swap
« Reply #3 on: April 08, 2021, 05:57:15 pm »
I agree with Shane - it seems pricey unless its some sort of locker.

You would notice the improved acceleration but it won't be that dramatic, and not enough to justify the cost. 3.50's would wake it up more and could be swapped into your own diff centre for less than that money I reckon.

Offline Dizzy

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Re: Diff Swap
« Reply #4 on: April 09, 2021, 06:29:11 am »
The diff is a factory equa-lock unit..

Online GEOFF289

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Re: Diff Swap
« Reply #5 on: April 09, 2021, 08:51:47 am »
Ok, I guess that makes it better value. However, the Equa-Locks are not regarded as being as effective as the later Traction Lock diffs Ford changed to.

How much mumbo do you have? Is a locker something you really need?

Offline GLENN 70

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Re: Diff Swap
« Reply #6 on: April 09, 2021, 02:46:44 pm »
Wow I can reply  :pepper: no performance gain from a 3.0 to 3.2

Offline Dizzy

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Re: Diff Swap
« Reply #7 on: April 09, 2021, 03:27:30 pm »
So 3.40/3.50 'ish makes more sense. Car has around high 200hp now but i want some more takeoff and overtaking punch. Not into drags/racing/track days so a locker isn't necessary. Think I will investigate a gear swap for my diff - recommendations for a workshop in Brisbane or the Sunny Coast and estimate of likely cost would be appreciated. Cheers

Offline birdman

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Re: Diff Swap
« Reply #8 on: April 09, 2021, 05:38:49 pm »
So 3.40/3.50 'ish makes more sense. Car has around high 200hp now but i want some more takeoff and overtaking punch. Not into drags/racing/track days so a locker isn't necessary. Think I will investigate a gear swap for my diff - recommendations for a workshop in Brisbane or the Sunny Coast and estimate of likely cost would be appreciated. Cheers

Glenn 70 would know of someone your way.

Rough estimates from 2 yrs ago
Gears $400
Bearing kit $250
Axle bearings? and seals $160
Plus labour $$$?
That's not including a locker.

Online GEOFF289

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Re: Diff Swap
« Reply #9 on: April 09, 2021, 08:08:32 pm »
Auto or manual?

Online Dwayne

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Re: Diff Swap
« Reply #10 on: April 09, 2021, 08:41:10 pm »
If auto, I'd go with 3.25 as it's good acceleration and stil keeps revs on the freeway manageable.

Offline scedd1

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Re: Diff Swap
« Reply #11 on: April 10, 2021, 05:02:17 am »
Put 4.11's in it for the traffic light launches.
Its not as if you will get over 80km/h on the Bruce Highway for the next 5 years anyway  :lmao: :lmao: :lmao:
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Online GEOFF289

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Re: Diff Swap
« Reply #12 on: April 10, 2021, 10:06:50 am »
4.11's will certainly make a difference but not necessarily all of it good. I certainly wouldn't go that low in a manual, you'll render first gear redundant.


Offline Dizzy

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Re: Diff Swap
« Reply #13 on: April 10, 2021, 02:13:54 pm »
Car is an auto.

Offline Chris66pny

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Re: Diff Swap
« Reply #14 on: April 10, 2021, 03:11:51 pm »
I have the same size wheels and an auto, I switched to 3.55 gears and it's been good around town, nice and punchy off the lights just sits a little too high in the rev range at 110-120 on the highway (about 2900rpm)