Yes they are lightweight. They become an issue when you get larger tires. The issue arises not off road but on the highway. When geared down in 4low they rarely break because there is less stress on them in these situations.
The problems arise when you on underpowered on the highway and roll around with the pedal floored to get your speed up. That's when they usually develop problems. Often what goes is just the 5th gear as it is held on by a snap ring that can pop off....as I am experiencing right now.
As for replacements nothing will simply bolt in. If you get an AX15, which is probably the best option you will need to get a new bellhousing. Plus the shaft on an AX5 is 21 splines and an AX15 is 23 I think. Therefore some modification will be required. Also, your driveshafts may need to be shortened or lengthened. It turns into a modestly expensive job when you consider you can get a used AX5 for $250-$400 and rebuilt one for $750.
This is a dilemma I have faced for years. I have gone through 4 AX5s but each time I simply replaced it.
My Jeep - Video
My Jeep in the Snow
92 YJ, 35' MTR Kevlars, Klune/Dana 20, 4.88s, SYE, Rubicon D44s w/Rubicon lockers, front and rear Alloy USA chromoly shafts with 30 spline outers, JK electric swaybar
, T&T tube fenders
, custom cv driveshafts, RE 4.5 XD springs
, M.O.R.E. 5/8'' boomerang shackles + 2' BL, 15lb Powertank, 4.0L TB & TB spacer, ARB Snorkel, K&N filter, rear bumper and tire rack, Rancho 9000s, AtoZ Rockers
, Skid-Row Engine skid plate
, Teraflex Bellyup, JCR Offroad 1 Ton TieRod
, rock lights, RE hand throttle, M.O.R.E. roll cage, corners
, 9000lb winch with synthetic cable in-cab winch controller
(12voltguy.com), Dual Blue Top Optimas with 12voltguy
dual battery controller, a/c (ackits.com)
Originally Posted by joshrad
This Uncle Paul guy seems to know what he's talking about.