Changing Changing AMC 20 2.73 to 3.73 - advice on carrier change out? - JeepForum.com
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Unread 05-02-2013, 12:23 AM   #1
Colt44
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Changing Changing AMC 20 2.73 to 3.73 - advice on carrier change out?

It would seem that I'll need a "3.07 or greater" carrier in order to change the gearing on my AMC 20. My understanding is that "carrier" is the same as "differential" in terms of ordering the part. Question is, will I have to buy the whole carrier with all the parts, or can I get the bare diff and move the guts over?

Alternatively, what if I wanted to take the opportunity to install a PowerTrax?

Please help me get my head around this...

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Unread 05-02-2013, 05:12 AM   #2
keith460
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You only need to purchase a bare carrier case with no internals. You move all the spider gears, thrust washers and pin from the old carrier case to the new one. As for the option of purchasing a Powertrax unit, that only requires removing the spider gears, thrust washers and pin and putting that unit in place of. They are considered the 'lunchbox" type posi units which requires no removal of the original carrier case, everything stays where it is.

Dana 30 axles require new carrier case when using gear range from 3:07-3:54 and a another for 3:73-5:38

AMC 20 axles require new carrier case when using gear range from 3:07-5:38

Example: My factory gears were 3:31 and I changed them to 4:10's. I only needed to purchased a new front Dana 30 carrier to do the swap.
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Unread 05-02-2013, 11:06 AM   #3
Renegade82
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I agree with Keith. I did this same change back in the mid 90's. New carriers, new gears (R&P), new bearings, shims, and seals. But I had bought a rear TrakLok carrier with all the guts.
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Unread 05-02-2013, 11:55 AM   #4
Matt1981CJ7
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Quote:
Originally Posted by keith460 View Post
You only need to purchase a bare carrier case with no internals. You move all the spider gears, thrust washers and pin from the old carrier case to the new one. As for the option of purchasing a Powertrax unit, that only requires removing the spider gears, thrust washers and pin and putting that unit in place of. They are considered the 'lunchbox" type posi units which requires no removal of the original carrier case, everything stays where it is.

Dana 30 axles require new carrier case when using gear range from 3:07-3:54 and a another for 3:73-5:38

AMC 20 axles require new carrier case when using gear range from 3:07-5:38

Example: My factory gears were 3:31 and I changed them to 4:10's. I only needed to purchased a new front Dana 30 carrier to do the swap.
Keith,

Boy, how some pics would help to get my head around this post.

hint hint....

Matt
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