AMC 20 Trac-Lock

[carriss]

I Was Looking into Maybe Finding A trac lock 20 rear and putting it in my J10 Anyone Have Any info On Which FSJ Models It May have been used in? And What Your opinions are on it, Any Info Could be Helpful,

Thanks, Guys.

 

[SteelHeadz]

From what i know, AMC 20's are weak as a stock unit. The Hub and axle shafts are splined and held by a Nut. these splines tends to strip on hardcore wheeling. this is remedied by Replacing the axle shafts with a one piece shaft available from 4WD.com or Quadratech. The other upgrade for the AMC 20 is to install a Truss across the axle. it will help the axle tubes from flexing too much and possibly developing a leak between the axle tubes and the differential housing.

 

[carriss]

My Rear end Came with the one piece axle stock, Do you Know What Model FSJs Came With A Trac-Lock, What Gears Were Available with it and if the vin is a good way to id a trac-lock model?

 

[Collin the Hen]

What about a locker? I'm going to weld my axle tube to the diff case. I've read that it helps it from bowing. Adding gussets help, too, of course. I'm also going to weld the individual spider gears in between the "unused" teeth, grind them down smooth, and stick them back in. Also, if you have another set of spiders, you can put them back in later. It's like the poor man's ARB
Jeep Axle: AMC 20 There's a link for amc 20 specs.

 

[carriss]

when I ran My Vin At FSJ VIN Decoder
It came Back and said

Year: 1980
Jeep Corporation
Toledo/4-Speed/LHD
Truck/J-10/131 in. Wheelbase
6200 GVW
I6-258 2V/110 HP

would the d in "LHD" mean it was a 2.73 open diff, I thought it was open but i also thought it was 3.08's thought i read that in my haynes manual But i Can't Find It Now

 

[SteelHeadz]

Is there no Tag on the Differential cover that indicates the gear ratio?

 

[Collin the Hen]

LHD could have meant left hand drive. Sometimes those tags rust off (did for mine), but there should be a pressed code to the left of the diff cover. I guess if you're really itching to know your ratio, you could pop off the cover and look on the ring. It may be time to change the fluids, too. It wouldn't hurt.

 

[carriss]

me And My Buddys Tore down, and Installed a Lincoln Locker in my dana 70 i bought and it's 4.11, so when i redo my brakes and do a soa on the front i'll gear the 44 down to 4.11 too,

 

[Collin the Hen]

You're putting in a Dana 70? Wowza. I guess you can forget about the lil AMC then, huh?

 

[carnuck]

For a Compatible Model 20 rear for your J10, it would be '80 to '88 (last year of the full size trucks) Prior to that, the rear axles were RH offset and only D44s in J10s. J20s came with full float Dana 60 8 lugs.
The Model 20 in '80 to '86ish 4 door wagons and narrow track 2drs was narrower by @7". The Widetrack full size Cherokee 2 doors (not all 2drs are widetrack either) '80 to '83 have the same front axle as the '80 up J10, but the rear is about 4" narrower.

The Model 20 ratios were 3.31 and 2.73 except tow package with 5 speed which could be 3.54 or 3.73.

 

[fullhouse]

getting up a Dana 70 is quite great for me rather than getting AMC 20. Why still pursue in getting AMC?