axle question

[Paul Voth]

Should i replace my AMC 20 for a dana 44??? (like I have in the front)??

If not----what then should I do to the replace the axels and brgs or just the bearings??

Dont the Grand Wagoneers (84)have solid axels. Are they floating (whatever that means).

If I should replace the 20 then do the gears is the front have to be the same as the ones in the rear????

I drive my FSJ about 100 miles a day!
And it is loaded down with tools, also use for camping\modeate 4x4ing but always loaded down????

what so you think?

[Brenton]

The only reason to swap to a DANA 44 would be the additional durability (As I understand it). The DANA 44 would also have more readily available conversions (IE limited slip, and lockers).
Every differential (again, as I understand it) is a floating axle. The only time you get into solid axle on DANA is to get up to a DANA 70, and then choose that as the option. Those axles are the heavy duty stuff they use for some 3/4 tons and most 1 tons.
If you swap out the axle, you will want to precisely match the current gear ratio. If you change it, yull be fine in 2WD, but look out if you switch to 4.
If you aren't experiencing trouble with the current diff, then I'd just leave 'er be. Somebody else could verify this, but I think the AMC 20 is a tad on the whimpy side, but won't get stressed if you aren't doing serious 4 byin'. If it dies, then I would seriously consider going to a DANA 44. Parts availability and price just can't be wrong.

Brenton

[joe]

Paul,
Leave your rear axle alone, it's fine for what you're doing with the Jeep. The AMC 20 is a good tough axle. The 20 got a bad rep from the AMC 20's installed in the CJ's. They had two piece axles that were the weak link but FSJ AMC 20's have one piece axles and are fine. The only really bad thing about the AMC 20 era is that they came with really poor axle ratios for any kind of offroading or towing. 2.73 stock and 3.31's optional with the tow package(what a joke). Only in some of the J-trucks could you get more realistic gearing but you can change yours to about anything you want, all it takes is money but no more than to swap gears in a D44.
All FSJ's have solid axles front/rear except for the early 62-65 ones that had the optional IFS(Independent Front Suspension).
All FSJ rear axles are semi-floating except the J-20 trucks and earlier versions of the J-series trucks that were 3/4 ton or up. Full-floating means the axle actually floats in the hub/housing and doesn't support the weight of the truck. The housing and hub does this. On a full floater you can pull the axle shaft out of the rig with the tire still bolted on the rig and sitting on the ground.
DynaTrac used to have a page that was pretty good at explaining various axles, lockers etc for the novice. It was at:? http://www.dynatrac.com/dyna4x4.html

-joe

[scotty]

well said, joe.

i just wanted to add that i have been running an amc 20 in my grand wag for over a year with 38x15.5 inch tires. the 20 is every bit as strong as a 44 if it is equipped with one piece axles. the only real bad thing about it for serious off roading is the big round diff hangs down lower than a 44,giving you slightly less ground clearance.

if you need to replace axle berings,simply pull the axles and run them dow to a shop that specializes in drietrain type work- they can press the old bearngs off and the new ones on for you. there is no reason to replace a whole axle shaft unless it has been driven long enough with a bad bearing that it is worn,scored or otherwise broken.

this is another good case for "if it aint broke,dont fix it"



------------------
scott
85 grand wagoneer
258/904/twin stick dana 300/dana 44/welded amc 20
38x15.5 gumbo mudders
snorkel/dual batteries/onboard air/"custom" convertable
3 inch body lift/mostly stock suspension/"modified" fender openings
custom front/rear bumpers and brushgaurd

[Shane]

I read at Randys' Ring and Pinion site on the web that the "AMC 20 ring and pinion are larger and stronger than the 44s'".
He does also say that using two peice axles is like using dental floss for a tow rope .
Us FSJers don't have to worry about that

Shane

------------------
1982 J10 Model 25
My Daily driver since
1988

[jamchico]

Where does the Dana 30 fit into this? Thanks for the low tech explanation (I think I almost understood it all).
Allen
69 wag
(post #30 YEAH!!)

[joe]

<BLOCKQUOTE>quote:</font><HR>Originally posted by jamchico:
Where does the Dana 30 fit into this? Thanks for the low tech explanation (I think I almost understood it all).
Allen
69 wag
(post #30 YEAH!!)<HR></BLOCKQUOTE>

Well to start with...when you have a "new question" on an existing thread you need to start a "new" thread...

The D30 front axle was used in 1971-73 Wags but not J-Trucks. Your 69 Wag(if stock) has a D27A front axle and a D44 rear.
-joe

[bigjeepguy]

The AMC 20 is not a bad axle, it is bigger and stronger than a Dana 44, and has lockers and gears available for it just like a 44. I would keep the 20, maybe put a truss on it if you are carrying heavy loads, but I think that you should be fine with a 20.