After spending many hours reading the Factory Five Forums while waiting for my kit, I was dreading having to install the differential. The thing weighs nearly 100 pounds and needs to be lifted input shaft first up into the frame, leveled above its mount points, lowered into position, and attached with threaded bolts aft and through bolts forward. Often it isn’t a perfect fit. I contemplated asking some friends for help but around 9PM on a Sunday I decided to take a stab at doing it single-handed with some ratchet straps. I started by wrapping a single strap around the forward arms and anchoring them to the open roll bar mounts. A few pulls of the ratchet and it was off the ground. I placed some strap 2×4 under it, released and reset the ratchet, and brought it a few more inches up… repeat, repeat. Once the input shaft was well above the crossbar, I put another strap around the rear of the diff and hoisted it level. After releasing some tension on the straps, it dropped roughly into place. I begin mounting with the rear threaded bolts having only pushed their sleeves partially into the bushings. This allowed me a little wiggle room and the bolts threaded in perfectly, pulling the sleeves flush into the bushings. I released the tension on the rear strap and moved to the front. A few light taps of the through bolts with the blow hammer and everything went into place with minimal fuss. I job I had been dreading took only 30 minutes!
Prepping the Differential
Before the kit arrived, I purchased an iron 3.55 ratio differential from a wrecked 2018 Mustang with 17k miles. Since I am using the Mustang’s independent rear suspension, this is the required differential. I could have purchased new, but these things are tanks and I saved a few hundred bucks. Becuase it is used (the only used part I will use), I elected to pull and replace the axle seals. With a puller it wasn’t a difficult task.
Before replacing the seals, I prepped the housing for a coating of POR-15 with their Cleaner and Metal Prep products. The POR-15 went on easy with a brush. Wear a mask with this stuff!
Quick tip for POR-15 users: After opening POR-15 it can be hard to reseal and this stuff can rapidly cure in the can during storage. To avoid that, consider never “opening” the can! Use some self tapping roofing screws with the rubber washers to create pour and vent holes. Replace immediatly after filling your paint cup.