I pulled the 9" rear end out of the Mav.to have it shorten by about 2" and found that the axles are threaded near the spline at the end. It's a 31 spline and I'm being told they can't be shorten because of the threads right below of the spline. Anyone hear of this or seen this? Is this normal
From what I know about 9' axles - any 31 spline made 1972 and earlier can be shortend. The reason being is a straight axle shaft on the older units vs a tappered axle shaft on the newer ones. Are these threads actually the turning marks in the steel? What year 9" do you have? Eric
I really don't know what year it is as it was already in the car when I purchased it. I do know it is a nodular rear with 3:50 gears/detroit locker.The tires stuck out a bit too much for me so I know the rear is wider than the stock Mav rearend. As far as the axle goes it is not tapered. Looking at this axle from the spline end down to the bearing, right after the splining there are threads..looks like a fine thread...approx. 3" long. When the threads were put in,metal was removed and thus the splining can't be done. I guess if I were going to shorten the rear more than 5" I'd be ok but only going 2" or so I can't. Actually if I'm not mistaken I think it's threaded on the bearing side as well. (don't have the axle to look at right now since I'm at work shhhhh! haha) Someone told me yesterday that the treads were put in so if it were to break it would do it there.I know there is a tag on the carrier with the codes and I can get the info later today. I think the rear may have come out of a '70 Torino but not really sure.
How much were they going to charge you to have the axles re-splined? You can get a new set of much stronger axles from Strange Engineering or Moser Engineering for around $300
I just had someone measure the bolt pattern and it measured 4 1/4 "" Yea I think the way to go now is to buy the after market axles. Guess I am puzzled as to why