The 9-inch Ford rearend has been the standard all-around bulletproof rear gear for years-in fact it's been the leader since its introduction in 1957. Back in the day, the big Olds rearends were found in many high-horsepower drag cars and things, but they too had to endure some mods to hold up and plenty were still blown up. Withstanding that brief period of competition, the 9-inch has always found a home under the frames of countless hot rods, trucks, customs, musclecars, and not to mention all the production line cars and trucks from Ford that were born with them.
To accommodate the ever-growing numbers of these vehicles that still require the brute strength-and then some-of the old 9-inch, the enterprising folks in the aftermarket have stepped in. Because of this it's almost prohibitive to try and use and old unit to suit your needs. Today there are more variations and options available than ever before with many of them being a bolt-in to your custom application-just add oil!
Moser Engineering is one of the heavy hitters in the rearend game, and in the last 24 years has seen more than its fair share of axles. We are going to check out what goes into one of their new 9-inch rearends from start to finish-beginning with a glance inside a complete aluminum center section.
This center section in the build pictures is almost exactly the same as the one going in the Roadster Shop chassis that's waiting for a '58 Suburban body except that ours has a nodular iron case and the one shown at Moser has an all aluminum case that saves up to 14 pounds over the iron version. The iron case is heat-treated and stress relieved before any machining is done while its lighter brother consists of 356-T6 aluminum with 7075-T6 aluminum caps and billet steel adjusters and relies upon its super strong thru-bolt design to give the case increased strength and decreased ring gear deflection that's common in most other aluminum case designs. Basically-you can't go wrong with either one-it just depends on how much coin you have to invest.
In this story, we'll be using Moser's housing, axles, and third member, which will eliminate the possibility of parts not working together, evident in the smooth way in which the whole build transpires. After going through all the steps here, all that is really left is to break-in your new rearend. Moser recommends doing that as follows for street applications:
1. With the car still on jackstands and the rearend filled with proper amount of non-synthetic lube.
2. Run in forward and reverse for approximately 2 to 3 minutes.
3. Drive vehicle approximately 10 miles at normal operating speed including accelerating and slowing several times conservatively, then let your truck cool for one hour.
Remember to do all this as safely as possible, and you can always call Moser's tech line for help. After all of this, you'll know that your rearend won't be the weak link in your drivetrain.
Here are all the parts that will go into building one of Moser's 9-inch center sections. Just looking at this picture makes me happy that they'll be putting this together and not us! |
These parts will be pre-heated to make their installation easier. The time in the oven will expand things just enough to avoid the struggle of getting them to fit into place. |
Cleaning out the case after the manufacturing and machining process is critical to remove any metal particles and cutting fluids. |
Here is an example of having the professionals at Moser do the work. There are a few things that need to be installed in the pinion support using a hydraulic press and specifically machined tooling, like the front pinion bearing race, rear pinion bearing race, and the pinion seal. Having the right tools and know-how makes all the difference for long-lasting performance and reliability. |
For the tougher Pro Gear third members, they machine a solid pinion spacer specifically for each center section as opposed to shims that work well for hi-po street stuff. Here they are checking the finished spacer with the calipers. |
Fresh out of the oven the pinion bearing will drop into place on the pinion shaft and is topped with the freshly machined pinion spacer. |
Now that the pinion assembly can be mated to the yoke, they test the preload of the pinion bearings on the press before continuing. |
With the pinion assembly deemed perfect, they turn their attention to the case and start by installing the pilot bearing for the inside end of the pinion. |
With enough thread lock in the pinion support stud holes, the studs can go in and the gasket and shim slipped over the studs. It's especially important with the aluminum case to have studs to hold the pinion support in, as opposed to bolts. That way the threads in the case don't get stripped or damaged during service. |
Things start to look pretty serious when the pinion assembly gets settled in. |