Strange S60 & Moser M9 Rearends - Bullet Proof Backends - Tech

The factory driveshaft comes out-it's too short and lacks the correct rear U-joint to work with the M9. The torque arm comes out using the same procedure detailed for Jensen's car. Note: In the upper right of the photo the brake lines have been disconnected at the body so that the large gray bracket on the rear can come off attached to it. There are two separate brake lines running to this car's rear; this is to accommodate the four-channel ABS system, so that the passenger and driver brakes can be independently modulated (a must for TCS).

Now a trans jack is placed under the rear and the Panhard rod is disconnected at the driver side. The ABS harness is unplugged from the body. After removing the rear LCA bolts and nuts at the bottoms of the shocks, the 10-bolt can be lowered out. Steer the parking brake cables out of their guide brackets as you do this (interestingly, not all cars have these). Pops and buddy Tom take a break from working on a far less important garage project-a P.O.S. 1972 Wheel Horse tractor recently acquired for $0-to lend a hand.

In lieu of purchasing a new set of 1998-2002 brake backing plates from GM, we opt to disassemble the 10-bolt so that we can pirate the old ones for use with the M9. We start by removing the rear cover's 13mm bolts and, with the cover off, unscrew the pin on the diff using a 5/16 wrench. Then we can pull this retainer piece out.

The axles are not quite free yet. One must pull each axle back and forth a few times to get its C-clip to fall out (also twist the axle if necessary). Once you hear the clip fall into the centersection, the axle can be gently glided out the end of the tube. Now remove the four bolts and nuts holding the backing plate (shown), and the plate will come off the end of the axle tube. Repeat for the other side.

Like nearly all aftermarket rear axle assemblies, the M9 does not use a weak C-clip retaining mechanism for its axles. For this reason, a press must be used to install our old backing plates onto our new, high-strength Moser axles. Moser includes all hardware needed to do this, including one bearing and one retaining ring per axle (technically, the backing plates themselves do not press on-they just must go on before the bearing is pressed in place). The procedure requires a lot of force, and much precision, but TTP's Nick Stevko has been down this road before and knows how to get it done quickly and safely on the shop's hydraulic press.

Back in the Werner garage, other items that must come off the old 10-bolt are the LCA brackets (or, if you will, "parking brake/brake line brackets") that straddle the rear LCA bolts. In attempting to fit them to the M9, we find that some trimming is required: a bit to clear the new 3-inch axle tubes, as well as some more about the inboard LCA bolt hole (finger pointing). This material needed to be cut down to reduce interference with a weld on the M9 (that weld also had to be ground slightly on the passenger side).

Another bit of fabrication required with the M9 are provisions to attach an antiroll bar, as none are provided. We measure the spacing between the mounts on the stock rear and come up with 31.5 inches. The lower portions of 3-inch muffler clamps are then welded to the bottom of the Moser axle tubes, noting that one side of each clamp must be trimmed thanks to our optional back brace (which, by the way, can be had for $140 installed). Important note: When measuring for the mount locations, use distances from the end of each axle tube, NOT from the apparent middle of the rear-the center portion of a 9-inch is offset to the driver side!

We're about ready for assembly, but before proceeding further, a full internal cleaning of the M9 housing is in order. This is best done in multiple stages using Brakleen and paper towels, but be careful with this stuff as it will harm the powdercoating on the outside. With the cleaning done, the ten studs that will secure the 9-inch's pumpkin are double-nutted and installed with threadlocker. The housing is then turned 90 degrees in preparation for dropping the pumpkin in vertically, and its gasket is laid in place.

Moser supplied our nodular case setup with a 3.70 Motive Gear ring-and-pinion and Truetrac differential, a gear-type unit that won't wear out like clutch-style posis. Schedule your hernia surgery in advance, as the weight of this sucker alone is 80 pounds. An aluminum case is also available for weight savings, though Moser did not recommend this for our soon-to-be-nitrous-injected application. We find that it is a bit challenging to install onto the studs. Even with them perfectly lined up, tolerances are so tight that we had to resort to careful hammering of the case to guide it on enough to start the nuts, then pull it down the rest of the way turn by turn. The ten nuts were tightened with washers underneath, and we used some threadlocker just to be safe.