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New Power Wagon Axles In An Early Dodge Ram - Four Wheeler Magazine

Pete Trasborg Brand Manager, Jp

We never were that thrilled with the axles that came from the factory under our ’94 Dodge Ram 1500, also known as the Long Range Clunker. Up front was a CAD-inflicted Dana 44 with weak ball joints and out back was a Chrysler Corporate 9.25-inch assembly. Both left the factory stuffed with a lackluster 3.55:1 gear ratio. With the 35-inch tires on the truck and the towing duties it sees, we needed beefier axles with better gearing.

bolt In Beef grinding On Rear Axle Photo 35629999

Mopar announced early in 2009 that the big AAM 9.25-inch front and 10.5-inch rear axles commonly found under the current Power Wagons would be available through Mopar at your local dealership. The axles came stuffed with good stuff like 4.56:1 gearing and electronic lockers not to mention huge axleshafts and front and rear disc brakes. We knew all of this, and still spent over a year trying to find a set of junkyard axles from a ’94-’02 3⁄4- or 1-ton truck. Why? Well, despite all of our contacts within Chrysler, no one could tell us if we’d have to completely redesign the front suspension brackets on the Power Wagon axles to work with our ’94 Dodge Ram.

We couldn’t find any junkyard axles near us that weren’t totally hashed and anyone who had them and was willing to part with them wanted at least $1,000 for the front Dana 60, and another $500 for whichever rear axle they pulled out of the truck along with it. While many of the 3⁄4- and 1-ton trucks came with 4.10 or 4.56 gears, we weren’t about to pay $1,500 to get into a set of axles that would then need a complete rebuild. We did manage to find some junkyard axles back east for reasonable prices, but shipping them to the southwest quickly became untenable.

So, after spending way too much time chasing junkyard parts, we checked out the Mopar axles a second time. What we found surprised us. With an MSRP of only $3,904 for the front axle and $3,504 for the rear axle, delivered to our local dealership, stuffed with all brand-new parts, the gears we wanted, and electric lockers to boot, we decided to take the plunge.

Once we ordered the axles, we enlisted the axle-swapping experts over at Off Road Evolution to help us get them under the truck. The company is known for custom installation work, but also has experience manufacturing high-quality suspension components so if the front axle became a nightmare we would be in good hands. We knew we were going to have to swap wheels but beyond that we didn’t know what to expect. What we found out surprised us, and just might surprise you too.

Just the Facts
Here are all of the critical measurements we took while comparing the new and old axles. We didn’t actually record the spring perch spacing of the rear axle, because the locations on the new axle weren’t even close enough to be used. We knew we were chopping them off from the beginning.

All measurements are in inches.

bolt In Beef axle Fact Chart Photo 34570406

Dollars and Sense
While the Power Wagon axles seem like a smoking deal on the surface, we had to add a lot of parts to them to get them under our truck and functional. Many of the parts were only available through Mopar, though we did find some at our local parts stores. All part numbers in our chart (right) are Mopar numbers unless otherwise noted. The prices for the Mopar parts were largely found online at Factory Mopar Parts, which has good prices on just about any currently available factory Mopar part you might need. The rest were found in a quick Internet search for what you might actually expect to pay in the real world (rather than MSRP). Keep in mind that this is what the cost to modify our driveshafts was. If yours are in better (or worse) shape, plan accordingly. And, obviously, this tally doesn’t include wheels and tires. Pick yours to suit your tastes and budget. This is just what it takes to get the axles in the truck and functional.

bolt In Beef axle Cost Chart Photo 34570370

PhotosView Slideshow The first step in a swap like this is to measure carefully. Mel Wade, the owner of Off Road Evolution is measuring the center-to-center of the coil spring mount on the old axle. We compared control arm vertical separation, control arm horizontal separation, coil spring, shock mount, and track bar locations before even attempting to formulate a plan of attack.

The first step in a swap like this is to measure carefully. Mel Wade, the owner of Off Road Evolution is measuring the center-to-center of the coil spring mount on the old axle. We compared control arm vertical separation, control arm horizontal separation, coil spring, shock mount, and track bar locations before even attempting to formulate a plan of attack.

See the “Just the Facts” sidebar for the fruits of our measurements. What we found out was that all the critical measurements were within what was likely to be acceptable. So, we slung the front axle under the truck. The coil spring mounts, shock mounts, control arm mounts, and even the track bar all were close enough to line up without welding, drilling, or any other fabrication.

The difference in horizontal separation between the old and new axles was well under an inch. However, the vertical separation between the two varied by 11⁄2 inches. You want the upper and lower control arms to be as close to parallel as possible to minimize caster and pinion angle change as the suspension cycles. We were worried about the 11⁄2-inch change, but Wade tells us that having the control arms further apart at the axle is more desirable than control arms that are further apart at the frame. If they are further apart at the frame there is more likely to be unwanted caster and pinion-angle changes as the suspension cycles.

We re-used the stock ’94 cam bolts, which provide for caster adjustment. The factory ’94 cam washers measure 13⁄4-inch-diameter while the cam bracket on the Power Wagon axle measures 2 inches. While this 1⁄4-inch space is less than ideal, to go to the stock 2010 cam bolts, we would have had to ream or replace the bushings in the Rough Country control arms. Since most of the impact the front suspension absorbs is trying to push the axle rearward, we will align the cam washer so it rides on the front of the cam bracket. Unless we hit something in reverse going really fast this should work for us for the life of the truck. If not, we will make new 2-inch-diameter cam washers by hand. Note the silver paint marker line Off Road Evolution puts on every bolt after it is torqued to spec. The line shows visually at-a-glance if the bolt has come loose and also shows that the bolt has already been torqued, saving time re-torquing fasteners.

While the old and new axles share dimensions between steering arms, the old steering linkage is an inverted Y-style. This setup was used through 2008 on the Dodge Ram trucks and is less desirable than an inverted T-style. The inverted Y-style causes changes in toe-in when the suspension cycles and can lead to goofy tire wear and even death wobble. From 2009 on the inverted T-style eliminates the change in toe-in but can lead to a vague feel in the steering due to the drag link end at the tie rod rolling before pushing on the tie rod. This super-stout Mopar linkage available at KLM Performance eliminates both problems with the inverted T-style architecture by running the drag link tie-rod end vertically through the tie rod. The company also has a Borgeson-sourced linkage available.

Unlike the tie rods of yesterday, this new setup doesn’t use castle nuts. In its stock form, it calls for M14x1.50 Nylock nuts. They come with the full kit from KLM performance along with the pitman arm with the correct taper but we didn’t need the pitman arm and thought we’d find the nuts locally. Unfortunately finding these nuts is easier said than done. After searching five different local hardware stores we gave up and dove into Off Road Evolution’s random bolt box to find what we needed. If you are planning on putting this steering linkage on at home, order at least the M14x1.50 nuts so it all goes smoothly.

We were able to reconnect our factory sway bar with the new axle by using Jeep JK sway bar end links. This shows the axle at full droop. Check your local 4x4 shop. If the company installs lift kits on the new Wrangler chances are these things are being thrown away hand-over-fist and it is likely you can get them for nothing, or next-to-nothing.

Another somewhat unexpected benefit was the huge increase in factory braking between a ’94 1⁄2-ton, and a ’103⁄4-ton truck. Not only are the rotors on the new axles bigger, but both front and rear brake calipers are dual-piston units with larger pads providing more stopping force. This will make a huge difference in stopping a heavy trailer. Shown here from top to bottom are the new front caliper, the ’94 front single-piston caliper, and the new rear caliper. Note the rear caliper is the same size as the old front caliper, and it is a dual-piston unit to boot.

We tried to re-use our factory parts wherever we could, and that included the factory hard rear brake lines. However, in going from drum to disc, we needed to come up with some new parts. We got the 8-inch flexible line (Dorman PN H97664) from our local parts store. This line is the right length to go from the rear caliper to the axle and has the correct 3⁄16-inch flare fitting to work with the factory rear brake lines. The banjo bolts (Carlson PN H9471-2) were used at all four corners and came with the copper crush washers. The proper way to do this is to use weld-on tabs to retain the junction of the hard and rubber brake lines, and we got ours from Industrial Metal Supply. We then took about 6 inches off the stock ’94 hard lines, reflared them, and secured them to the weld-on tabs with Carlson retaining clips (PN H1457-2).

For the rear axle, Off Road Evolution cut off the factory perches. After loosely bolting everything together and putting weight on the axle the pinion angle was set. Then the 21⁄2-inch-wide perches from GenRight Off Road were welded-on with the factory ’94 spring spacing locations. Returns from the end of the spring perch (seen here at the rear of the perch) were cut for the front and rear of both driver and passenger side perches and burned home for reinforcement. The rear shock mounts on the Power Wagon axles were close enough that the shocks bolted right in.

The old Chrysler Corporate rear axle and the new AAM axle were even close enough so that the factory ABS magnetic tone-ring sensor could be reused. We simply unbolted it from the old axle and bolted it into the new one using the old hardware. However, due to the drum-in-disc parking brake setup, we needed new cables. We ended up using ’02 Dodge cables that we got at our local parts store, which mated up with the factory cable coming down from our pedal.

The plugs for the electric locker connections are unique and only available at your local dealership at this time. Fortunately, it isn’t necessary to buy the entire Power Wagon under-body wiring harness. As you might imagine, we have amassed a ton of parts-counter contacts and one of them was able to find us a lower-dollar alternative. We coupled Mopar PN 68040492AA with Daystar Products Carlington-style switches mounted in the dash to activate the front and rear lockers.

The plugs on the axle have four terminals. In the factory Power Wagon configuration, two are for locker activation and require 12 volts. The other two are for the computer to sense positive locker activation and require 5 volts. Once the computer senses activation, it will turn on the dash indicator light. Since our ’94 doesn’t have any such bells and whistles, we will look for locker activation the old-fashioned way, by watching for tire slippage. Since we didn’t care if we fried the sensor, Wade tested all the terminals until we could hear the locker engage. Since the magnet on the locker doesn’t care which way power is flowing, we just had to find the correct terminals.

The connectors that activate the locker are catty-corner in the connector and need to get hooked up as shown. Note the location of the “ears” in relation to the front of the axle. The front of the axle is where the differential cover is—so for the front axle, that faces the front of the truck. For the rear axle, it faces the rear of the truck.

We needed to shorten and modify the driveshafts to hook up to the new, bigger, axles. We tapped JE Reel Driveline in Pomona, California, to help us with that. We didn’t want completely new parts, but our front driveshaft was cooked so the company ended up rebuilding it at the same time. The front driveshaft was shortened, got a new male and female splined slip-yoke, the CV was rebuilt with new U-joints, the AAM-specific yoke welded on, and then the entire thing was balanced. The rear shaft had been recently rebuilt, so it was shortened and the proper flange added to mate with the rear axle yoke.

The front axle yoke was the big problem, as currently it is available only direct from AAM. Fortunately, JE Reel moves enough of these style driveshafts to be on the short list of companies that AAM will sell to direct. If your local driveshaft shop can’t get the yoke, you can also pick it up from your local dealership (PN 68067348AA). We ended up with four different U-joints between our front and rear drivelines, which bothers us because we need to carry four different U-joints as spares. However, it didn’t bother us enough to spend the big dollars for all new drivelines to match U-joint sizes.

Even if our factory 16-inch wheels would clear the 141⁄2-inch front rotors and dual-piston calipers, we’d still need to go from the 5-on-51⁄2 to 8-on-61⁄2 bolt pattern. In the end we had to bump up to a 17-inch Mickey Thompson Classic II wheel to clear the brakes. We wanted good road manners for towing in all conditions but still aggressive and bulletproof enough to run off-road so we went with 35x12.50R17 Mickey Thompson Baja ATZ tires. While the Classic IIs only had 1⁄4-inch more backspacing than our factory wheels, we gained 13⁄8-inch of track width up front and 31⁄8 inches of track width out back between backspacing and axle width changes.

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New Power Wagon Axles In An Early Dodge Ram - Four Wheeler Magazine

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