Axle Truss

[Peanut Butter]

What are some of the designs ya'll have used on an AMC20 rear axle to addd strength to it? Weld the tubes to the diff housing, replace the axle with a one piece, and strengthen the over all axle with some sort of truss. What works the best, what size steel to use, etc. Plans for a future project on my wimpy stock AMC20 . Thanks, Rod

 

[CABBOTT]

I'm interested in hearing this discussion as well

 

[harleydragon]

no doubt that many of the things you mentioned would make it a little stronger but I prefer swapping in a 1 ton..everything is bigger and more heavy duty..full floating axles don't have to support weight but just transfer power

 

[Old Dog]

IMO you need all three, I had all but the truss and paid for it with a twisted and bent tube.

 

[alabamaboy54]

I had none of the above until I spun and twisted a tube on my AMC20 . I have since welded the tubes to the chunk with 4 small welds, leaving space inbetween for the metal to still expand and contract, added a Warn Full-floater kit with disc brakes (which is no longer in production, so the best option is the 1-piece axles) and added a truss over the top that I picked up from Eddie at groundpounderfab, Besrk is his name on the forum I believe. Have had no problems since the upgrades. If youre not very good working with metal I would look into the truss from Eddie, he makes them specific for the AMC20 which comes in 3 pieces that requires very little work to install

 

[Purple77CJ7]

I welded the tubes to the center section and ran some 3/8" x 3" flat iron across the top of the tubes and the center section welded on the edge. Tapered the ends down to about 1". I made it in three pieces so I could make it fit better.

 

[PaRenegade]

Some people always bust on the AMC20 axle. Yes, in it's stock form it not always desirable due to it's major downfall, the 2 pc. axle shafts. But once that's remedied it's much more reliable. I replaced mine back in the early 90's after spinning 2 hubs and learning my lesson. Luckily both times happened on pavement.
In my recent build I had the opportunity to improve on it some more. I had the tubes welded at 3 points around it's intersection and added a truss. I had a slab of 5/16" thick plate laying around so I made a template and had a friend cut it out on his plasma table. I doubled the top 1" with another strip of 5/16".

 

[jdarg]

no doubt that many of the things you mentioned would make it a little stronger but I prefer swapping in a 1 ton..everything is bigger and more heavy duty..full floating axles don't have to support weight but just transfer power

The OP has 32" tires. One ton axles w/ 32" tires would have the pumpkin scraping on the ground, figuratively speaking. They sound cool but not everyone really needs 1 ton axles and they are counterproductive with smaller tires IMHO.

OP, I would weld the tubes all the way around, install 1 pc. shafts, and call it a day. I don't think you need a truss - you don't have enough tire IMHO to get you into jams where you might need one.

If you were dead set on trussing it, I'd use tube, i.e. 2x4", and not plate. 3/16" should be plenty of thickness. 1/8" is probably fine too. But I don't think you need it unless you are jumping your rig.

 

[harleydragon]

The OP has 32" tires. One ton axles w/ 32" tires would have the pumpkin scraping on the ground, figuratively speaking. They sound cool but not everyone really needs 1 ton axles and they are counterproductive with smaller tires IMHO.

.

agreed..with 33's or smaller I have never done anything except go to 1 piece axles..but,I think that stock 1 tons will be stronger than a 20 or a 35 no matter how much you beef them..When I install 1 tons it is usually for 37's or bigger...

 

[Peanut Butter]

Thanks for the nice pictures, PaRenegade. If I were still in the mountains of Colorado, I would most likely go with a different axle. My 4 wheeling down here will be Limited to sand beach (Padre Island) and gravel/rock roads (Big Bend) for the most part. My tires will be wide for the flotation factor, not necessarily big. But given the non-availability of wide but not tall tires from the manufacturer, I may go to 33x12.5x15 instead of the 32's that are on it now. That being said, a truss may not be needed, but may just be extra insurance. I figured that there would be alot of people out there that had gone this route before making the big axle swap thing.

So, keep the ideas coming. All suggestions are appreciated. Rod

:grinjeep:

 

[IOPort51]

After doing the math on an AMC20 with axles, bearings, seals and a truss I decided that a Dana 44 was justifiable.

 

[Peanut Butter]

Isn't the Dana 44 a center mount diff? Rod

 

[IOPort51]

A what? please explain.

Isn't the Dana 44 a center mount diff? Rod

 

[Peanut Butter]

Doesn't the drive shaft on the Dana 44 come from the center of the setup as compared to the AMC20 which is offset to the passenger side? Rod

 

[IOPort51]

Rear axle is pretty much in the center on both. Not dead center but too close to matter. I did have to move the spring perches about 3/4 inch. The doner was a 1975 CJ5 .

Doesn't the drive shaft on the Dana 44 come from the center of the setup as compared to the AMC20 which is offset to the passenger side? Rod