AMC Model 15 spirit dl '82 axle code?!?!

hi, having said the above, I actually am going to be rebuilding an AMC15 in the near future, for my 77 Hornet AMX, 258/T5., w/.73 OD. Current ratio is 2.73, which makes OD useless anywhere below 75 mph, going to a 3.08. More money...more money..., it's ALL good.

I'd go with a 3.31 rear gear with that .73 OD at the least. My .70 OD was OK with a 3.08 (4.6L stroker, early AW4 auto/OD), but still had to be going over 70 to use OD. I switched to a 3.55 gear (stock for XJ, 4.0L, AW4) and gained an average of 3 mpg. With the five speed's lower first gear 3.08 will work a bit better than it did for me. I think the 3.31, being sort of between 3.08 and 3.55, might be the sweet spot for performance vs mileage, at least with the auto. With four forward gears before OD you would be fine with only using 5th at higher highway speeds.

The 15 is tougher than most think. If you're running typical street tires not much bigger than stock you will always spin tires, not shock the axle too much. Start running wider, stickier tires, limited slip and using traction control, and you can tax the AMC 15.

hi, Mr farna, thank you for your input, yes, 3.31 would be optimal , but, where to get those? That is the "carrier break" for the AMC15/Dana35. Everywhere I've looked, one may purchase the 3.07, or the 3.54 and up.  No 3.31 anywhere in sight. My current axle is the (stock) 2.73, not bad at all with the new T5, (from MDL, Modern Drive line, in Idaho). they offer the T5 in any configuration you want, and have their own tailsection,which will put the shifter anywhere you want, within a 10" space. That's why i went with them, that custom tailsection, put the shifter exactly, ok maybe a 1/2" off, from the stock Hornet SR4, so, no cutting trans tunnels, etc, Cost a pretty penny though, over $3K, Hey, you only live once!

AMC used a 3.31 in the AMC 15, but it doesn't appear to be made any more. Can find it for the AMC 20, but not the 15/D35. Sort of strange... but that ratio hasn't been used in anything of late. If you can keep 2000 rpm in OD while cruising you should be good. My 4.6L with a torque cam would easily pull 70 with the 3.08 gear and .70 OD, but it was only turning around 1750-1800 rpm. The motor would pull it, but it was working a bit to do it, so dropping to 3.55 increased mileage -- probably only 1-2 mpg on the highway, another 1-2 due to less work taking off, about 3 mpg overall. Just a couple hundred more rpm puts the motor enough higher in the torque range to make a difference! Nothing wrong with running 75-80 when you can, but I didn't want to shift a lot between 3rd and OD in the 65-75 range. Shifting into OD at 55-60 is what I want to do with the four speed auto, with a five manual going between 4th and 5th isn't as bad. My auto is manually shifted with a switch, but would have "hunted" a good bit if connected to the computer.

As far as I know Wranglers didn't get an AMC 20, but CJs did. Wranglers may have used a Chrysler 8.25" axle as an HD option, but most would just have a D35. There is an HD D35 with slightly larger diameter axles and bigger end bearings -- they may all use that (axle I pulled from an MJ was the HD version). That would still be a good heavier axle than the AMC15/D35. The D35 is actually a bit stronger than the AMC 15 used in cars, has slightly larger axle shafts even in standard form, IIRC. The Wrangler and XJ Cherokee axles are a bit wider than AMC small car axles, you would have to use deep offset wheels like the Eagle did (Eagle axles are same width as Wrangler/XJ).