Pros & Cons of the AMC Model 20

[LongHorn]

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Quote:
Originally Posted by Jroch
Will the axels help keep the rear end together on the 20, I have heard a lot of bad things about this rear end "which I have in mine also" and am looking to start getting things in place to repair or replace when I tear mine out, been doing a lot of research on the 44 as a replacement











The AMC20 gets a bad rap, but is actually a very good axle. The general opinion I've seen regarding the AMC20 is that with one piece axles it can handle 35 inch tires without a problem. Maybe another thread to discuss the AMC20 and its pros and cons is in order so as not to take over this thread. Read this AMC 20 Axle - Tech Articles - JP Magazine and do a search, there is plenty of info on this axle.

Read more: http://www.jeep-cj.com/forums/f49/w...oing-2626/index2.html#post21921#ixzz0VpkWwusY
​

 

[LongHorn]

I think most of the regulars know my opinion of this piece of ordinance is not very high, but I think it could make a good thread.

 

[LongHorn]

The only up side to this rear end is, it probably came in your Jeep so no extra cost. The ring & pinion is larger than the venerable Danna 44. That being said it has weak housing tubes, weak two piece axles,they're a PITA to set up the bearings.

 

[Old Dog]

Here it is from a guy with a V8 and 33's.


Cons.--The two piece axles
The tubes are thin (weak)
Drum brakes


Pros--As longhorn said it's free. Also everyone thinks they are junk, so you can buy used units and or parts very cheap. Good example, I got my detroit locker and a set of superior one piece axles for $200. from a guy who said he needed a 44.

Mine is still together after 5 years of playing in creek beds and hillsides. I don't go looking for mud and will avoid it if I can, and I never jump it. The rear tire has been in the air a few times climbing in the rocks though.

 

[mylittlecj5]

If you want to go a little wider and cheap, look into a FSJ Model 21 (its a model 20 with thicker tubes and 1 piece axles stock). Everyone thinks they are junk also, but I've been hearing good things about them since I got one in my parts pile.

 

[LongHorn]

If you want to go a little wider and cheap, look into a FSJ Model 21 (its a model 20 with thicker tubes and 1 piece axles stock). Everyone thinks they are junk also, but I've been hearing good things about them since I got one in my parts pile.

Aren't they six lug?

 

[Petescj]

Yes

Aren't they six lug?

 

[mylittlecj5]

Aren't they six lug?

Yep But there are ways to convert them if you really want to.
I am just going to use 6 lug wheels with mine, since the waggy 44 thats in the front is 6 lug also.

 

[Jroch]

Watching this thread closely as I make the decision on what to do with mine

 

[Petescj]

From pics you posted of the mud running Id ditch the AMC20 . Even with the tubes welded mud running will put too much stress on it IMHO.

By the time you truss it , 1 piece axles, locker, ring & pinion and all your better off taking it up a notch... or 8 .

Watching this thread closely as I make the decision on what to do with mine

 

[Jroch]

From pics you posted of the mud running Id ditch the AMC20 . Even with the tubes welded mud running will put too much stress on it IMHO.

By the time you truss it , 1 piece axles, locker, ring & pinion and all your better off taking it up a notch... or 8 .

I have full intentions of stepping it up, just want to make sure I make the right decision when I do, trying to get my ducks in a row for when I inevitably break the rear, right now looking at the 44 but open to any and all sugestions

 

[Petescj]

Whats the max tire size your gonna run?

 

[iCEMAN]

Have the 1-piece shafts, lockers, welded tubes and trussed setup in mine. Running 36" TSL's in everything from Rausch Creek to to mud bath we locally refer to as the Mounds (think thick frozen mud, which is about a foot of mud with 4 - 6" of ice on top of that for the winter runs).

No problems at all with it.

Think a lot of it depends on how you work the skinny pedal as to if you break it or not.

 

[Petescj]

You mustnt have seen his driveshaft in another thread.

Think a lot of it depends on how you work the skinny pedal as to if you break it or not.

 

[Jroch]

Whats the max tire size your gonna run?

I really don;t fore see going over 33"

 

[Jroch]

You mustnt have seen his driveshaft in another thread.

LOL, Believe it or not I was not hard on the pedal when that broke........ well maybe a little......... well ok I was pissed at the Transfer Case issues I was having at the time and that anger may have worked it's way down to my left foot but I swear the welds were weak on it..... yeah thats it weak welds.... yeah thats the ticket

 

[Petescj]

I really think you'll be fine with the above mentioned mods. 1 piece axles , weld the tubes and just to be on the safe side Id truss it. I believe 4wd hardware has one for the AMC20 . Even with a locker and 35s thats a pretty decent set up.

I really don;t fore see going over 33"

 

[BrockGrimes]

It's cheaper to upgrade the 20 than buy and build a 44, plus it's easy to convert the 20 to disc brakes also.

 

[mtruckstuff]

It's cheaper to upgrade the 20 than buy and build a 44, plus it's easy to convert the 20 to disc brakes also.

Pretty much a wash, price-wise between the two. If you can live with about 4" wider(or cut 'em), go with the Waggy narrow tracks. Higher spine count, more options and all that. Just a better engineered unit. If you have an early CJ, you need the Q-track narrow waggys to get a right side diff.

This outfit has disc brake conversion kits for about anything you can think of, including waggy 44's http://www.tsmmfg.com/

Paul