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Author Topic: amc rear axle ratio swap  (Read 3066 times)

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Dave69

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amc rear axle ratio swap
« on: February 17, 2017, 09:24:20 PM »


is it as simple as it sounds if i want to swap one ratio set from one axle into another?

in theory take out crown and pinion gears along with shims, then swap in the replacement set from other axle and bolt up, then check wear pattern
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UKJeeper

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Re: amc rear axle ratio swap
« Reply #1 on: February 17, 2017, 10:38:14 PM »

Others (who know WAY more than me) will be along, but..

I know that you may need to swap out the carrier, depending on how far away from stock gearing you go.
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JamesH

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Re: amc rear axle ratio swap
« Reply #2 on: February 18, 2017, 08:32:15 AM »

Check backlash with a dial indicator to make sure there is the correct amount of slack between ring and pinion. I don't know the AMC 20 but on Dana axles you should check pinion preload with an in/lb torque wrench - this is adjustedby either a crush sleeve or shims on the axles I've done. I think Bubba or someone will give better advice specific to the AMC20
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bigjeepzj

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Re: amc rear axle ratio swap
« Reply #3 on: February 18, 2017, 09:15:10 AM »

 :iagree:
the shims may need altering as the casting machining may be difference  for case to case


 
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Dave69

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Re: amc rear axle ratio swap
« Reply #4 on: February 18, 2017, 05:50:26 PM »

the carrier will be swapped hence the question, shims is the only real stumbling block hence the question, just wondering if a complete swap can be done without worrying about the shim issue too much
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Bubba

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Re: amc rear axle ratio swap
« Reply #5 on: February 18, 2017, 07:36:58 PM »

amc 20 uses a crush sleeve you will need a new one yes you can swap the whole lot over from one case to the other and keep the shims from the doner axle  but

check the contact pattern on doner before you take it apart  be very careful you keep them in order and put them in the same order in the case you are using  the contact patern WILL move even if only slightly but with your old shims in place it gives you an excellent jumping off or start point  just add or take shims out to get where you need

you need to try and get the contact pattern the same as it was do not try to get the perfect textbook pattern it wont happen on a used gear set

perfect time to fit one piece shafts the amc 20 is stronger than a 44 but suffers a bad rep due to the two piece shaft design
if using new bearings set to book specs for preloads if using used its less
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Graham

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Re: amc rear axle ratio swap
« Reply #6 on: February 19, 2017, 12:28:14 AM »

And that's why I just bring my axles to you....
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JamesH

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Re: amc rear axle ratio swap
« Reply #7 on: February 19, 2017, 09:01:50 AM »

Yukon do a good book you can download, I think I found it in Randys Ring and Pinion website that gives preloads for new and used bearings
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Dave69

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Re: amc rear axle ratio swap
« Reply #8 on: February 19, 2017, 01:52:33 PM »



cheers for the info
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Bubba

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Re: amc rear axle ratio swap
« Reply #9 on: February 19, 2017, 09:49:14 PM »

i have it i will look them up
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I spent most of my money on alcohol, women and old  iron........ the rest of it I just wasted.
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