Jeep Wrangler Axle Wrangling - Part 2 - Four Wheeler Magazine

Jeep Wrangler Axle Wrangling - Part 2 Ali Mansour Brand Manager, 4WD & Sport Utility

When it comes to modifying your 4x4, the line between need and want can be a tad blurry. Sometimes, you’ll get lucky (or unlucky depending on your point of view) and your 4x4 will give you a clear sign that an upgrade is warranted. This usually comes by way of broken parts. For us, our upgrade omen came by way of Dana 44 axles that were no longer up to task for our ’97 Jeep Wrangler TJ.

Last month, we gave you the rundown on our search for a rear axle upgrade for our V-8-powered TJ. The requirements for our Jeep included being able to handle 37- to 42-inch tires, easily support 5,000 pounds, and of course, gladly absorb spirited full-throttle assaults courtesy of the rig’s 5.9L Dodge Durango-sourced engine. In our previous installment, we narrowed our axle options to two all-new and two junkyard rear axles. Each axle carried a list of pros and cons, but ultimately only one made the most sense for our 4x4.

That rear axle of choice was the East Coast Gear Supply semi-float Dana 60. What made the East Coast Gear Supply 60 stand out from the pack? For starters, it’s fitted with all-new parts and made to bolt under the rear of a ’97-’06 Jeep Wrangler TJ. No scrounging in a junkyard or custom machining needed on our part to make it work. The fact that we could opt for it in a custom width rear axle was also desirable, mostly so we could create the exact track width we wanted.

Welding On Jeep Wrangler Photo 69554817 East Coast Gear Supply has been building, servicing, and selling differential parts of all types for years. Owned by wheeling-enthusiast Chase Perry, the company is well-known for its budget-friendly TJ 8.8 rear axle conversion. Currently, ECGS offers an assortment of bolt-in axles for a variety of Jeep applications. Since our Wrangler has a few unique aspects and components (such as our custom coilover setup and wheelbase stretch), we were fortunate to have their team of top techs and fabricators help merge the company’s standard-issue axle into our not-so-standard Wrangler.

While the 9.75-inch Dana 60 ring gear isn’t as large as the 10½-inch gear found in the junkyard heavyweight 14-bolt, it is more than enough to handle our tire and power needs. The fact that the Dana-sourced smooth-bottom 60 housing that East Coast Gear Supply uses has more clearance than the 14-bolt (and typical junkyard 60) also made it more suitable for running “smaller” tires, such as a 37. By now, I’m sure some of you are curious as to why we opted to go semi-float instead of full-float. The answer is simple. We don’t need the load-carrying capacity of a full-float axle.

A semi-float rear axle creates a lighter package overall, and when using a large Set 20 axle bearing (commonly known as a big bearing end) it is more than capable of supporting our platform and then some. Aside from the fact that a full-float axle adds weight, a typical full-float Dana 60 rear found in a junkyard would likely only have 1.31-inch, 30-spline axleshafts, which wouldn’t be a major upgrade over our outgoing Dana 44. Going with the custom semi-float 60 from East Coast Gear Supply provided us with extremely strong 1.50-inch, 35-spline chromoly ’shafts which are equal-length and extremely easy to source in the aftermarket.

To get even more detailed information on the East Coast Gear Supply Dana 60 rear axle, and place it under our Wrangler, we took a trip to the company’s headquarters in Raleigh, North Carolina. While there, we followed along as our new heavy-duty rear axle went from the builders table to the back end of our TJ. Be sure to check back next month as we finish out our Jeep Axle Wrangling series with a new front axle that has some clever tricks of its own.

PhotosView Slideshow East Coast Gear Supply’s Dana 60 rear axle starts with all-new components. Once you have chosen the axle’s width, the axletubes are cut to length and then pressed into the new Dana-sourced housing. Measuring 3 1/2 inches in diameter with a 1/2-inch wall, the larger axletubes are significantly larger and stronger than the factory TJ rear. Stock axle width on our Jeep Wrangler TJ is 60.5 inches. We opted to go with 65 inches on our new axle to increase the stability of the Jeep and better match our front axle that we will be installing next month. Once the axletubes are pressed, the axle’s ends are added. Since the ECGS 60 is a semi-float rear axle, the axle bearing ends are welded to the tubes. ECGS offers Set 10 (left) and Set 20 (right) axle end bearings. The Set 10 is what’s commonly found under the Jeep Wrangler JK Dana 44, and is a more budget-friendly option as it allows TJ owners to reuse their stock Dana 44 drum or disc brakes. We opted for the stronger Set 20 bearing ends as they can hold more weight and make the most sense for our application. To secure the low-pinion Dana 60 housing, the axletubes are plug-welded using .035 wire and MIG welder. Unlike older Dana 60 differentials, the new Dana-sourced 60 housing has a smooth bottom, so we have less chance of snagging it on obstacles off-road. To ensure that each rear axle can bolt directly into a ’97-’06 Jeep Wrangler, East Coast Gear Supply uses an axle jig to affix the company’s 1/4-inch TJ suspension brackets. To achieve the best pinion angle, ECGS set our differential at 17 degrees, which works perfect for our Wrangler, which is equipped with roughly four inches of lift. Since our TJ is running coilovers, we left off the coil buckets and shock mounts that come standard with the bolt-in TJ 60. Also standard with the ECGS semi-float 60 are 1.5-inch, 35-spline chromoly axleshafts. The axleshaft ends come pre-drilled with the TJ’s stock 5-on-4 1/2-inch bolt pattern and a larger 5-on-5 1/2-inch pattern. Since we are changing out our front axle with a more heavy-duty assembly, we’ll be using the larger 5-on-5 1/2-inch pattern. Parking brake, emergency brake, hand brake, call it what you will, but it was a must-have item for our street-driven Jeep. The ECGS 60 uses backing plates from a Ford 8.8 rear axle, which works perfectly with our Jeep’s stock e-brake cables. When it comes to strength and simplicity, it doesn’t get much better than the Detroit Locker from Eaton Performance Differentials. Given the automatic-style locker doesn’t require any external switches or levers to engage, it’s ideal for trail-oriented rigs where the time in the dirt outweighs the time spent on-road. We’ve had great luck with the Detroit Locker in the past and the massive full-carrier replacement Dana 60 version of the locker fits this build perfectly. One of the main draws of the low-pinion Dana 60 rear is the extremely strong gearset. Unlike a high-pinion 60, which turns on the weaker coast side of the gear when placed in the rear of a vehicle, the low-pinion rear 60 powers the stronger drive-side of the 9.75-inch ring gear. We opted for a 5.13:1 gearset and master install kit from Yukon Gear & Axle. Yukon is well-known for its line of heavy-duty aftermarket axle parts, and our numerically high gearset provides a nice balance of strength and gear reduction for our tire-turning needs. To finish out our braking system, ECGS uses new calipers, pads, and rotors originally designated for a Ford Explorer equipped with an 8.8 rear axle. Since the company has an in-house DOT-compliant brake line machine, it sends out each of its bolt-in 60 rear assemblies fitted with DOT-compliant steel-braided soft line and hard lines that are form-fit to the housing. Given the modest size of the new brake calipers, our TJ’s stock master cylinder should have no issue producing the clamping pressure needed. Depending on how your TJ is equipped, your rear driveline will need to be modified or replaced altogether. We sourced our new ’shaft from Oliver’s Custom Drive Shaft located in Winston-Salem, North Carolina. We selected the 1310 Dana 60 yoke option from ECGS, so Oliver’s built our 20-inch driveline with a 1310’s at both ends. The 1310 CV at the T-case provides enough operating angle for us to fully cycle our Jeeps 12 inches of vertical wheel travel. While our Wrangler is far from stock, the “bolt-in” aspect of the axle install was very straightforward. We didn’t experience any interference with our Jeep’s long-arm kit or track bar, and were even able to reuse the stock rear sway bar. Having a two-post vehicle lift makes the job easier, but it is completely possible to perform the rear axle swap in the comfort of your driveway over the course of a weekend.