SRD Introduction

Some common workplace health and safety hazards include getting struck by objects, and repetitive motion and ergonomic injuries. Companies that use, service and maintain semi-trucks as part of doing business are subject to greater occurrences of cumulative trauma disorders because the worker is required to work in confined and awkward positions while lowering, lifting or positioning extremely heavy drive-train components, such as the transmission, drive shaft, axels, and the differential. All of these components can be extremely difficult to work on due their size and locations, but especially challenging is the differential.

The differential, in the simplest terms, provides power to the vehicle, driving a pair of wheels while allowing them to rotate at different speeds. Many things can go wrong inside a differential that requires the removal from the housing unit for service, repair or replacement. Due to the location of the differential and its associated weight and size, servicing or replacing a differential can be time consuming, labor intensive, and can pose numerous worker safety issues. This is because the worker is required to work in awkward positions while lowering, lifting or positioning the extremely heavy differential and associated parts, which is conducive to work related injuries. Because of the size and weight of the differential, many of the injuries associated with differential removal are cumulative trauma disorders. These are injuries caused by overexertion, strains, and sprains. Mechanics, who often need to lift heavy objects, strain their muscles, bend over and work for hours at a poor posture. As a result, they often suffer repetitive stress injuries, such as muscle pulls, spinal injuries, wrist injuries, back sprains, elbow injuries, ulnar nerve entrapment, and carpal tunnel syndrome. In fact, one of out of every five injuries reported by mechanics in 2019 was some form of repetitive trauma injuries, according to The Bureau of Labor Statistics (BSL). The BSL data also revealed that heavy lifting accounted for more than 50 percent of all overexertion injuries in 2019. Other injuries associated with this type of work are a disk rupture or hernia, and smashed, broken, punctured, or cut body limb parts. 

In summary, most of the injuries and a significant amount of labor effort associated with differential removal/maintenance can-be-avoided by using advanced or specialized tools designed for such a task with an emphasis on safety.

SRD Description

With safety and simplicity in mind, 360 Effects LLC has designed and manufactured a drive-train safety removal device that is mobile, easy to use, and, most importantly, provides the mechanic a safe way to lift, lower, and move the differential with little or no manual physical effort.

The Semi-Truck Differential Safe Removal Device (SRD) consists of a structural steel tube brace beam with adjustable clamps so that the SRD can be easily moved and clamped to any part of the truck chassis for strength and stability. Attached to one end of the beam, is a 2500 lb ATV Winch (with wireless remote) that uses 5/32“ aircraft grade steel gauge cable with a 2500 pound line lifting/pulling capacity. The ATV winch cable is strung over a center-mounted pulley with the end attached to a snatch block. Additionally, there are two alignment studs that the mechanic inserts in to the differential at 3 and 9 o’clock for alignment and ease of sliding the differential out of the rear end case. This allows the snatch block to center over the top differential bolt at 12 o’clock, which the snatch block will connect too for lifting and lowering. Once, the differential is connected to the snatch block, the entire lifting and lowering function is controlled by remote operation. The differential can be lowered to or picked up from a piano style dolly, eliminating the need for mechanic hands-on interaction with the differential other than adding or changing gear oil or removing differential bolts.

The SRD is simple in design and operation while drastically improving differential maintenance and replacement labor time and worker safety, thus creating a Win-Win Solution for all involved. However, the SRD functions just as effectively for the handling of a transmission, drive shaft, and axel, all with safety and ease of use as the primary benefits.

How It Works

It is actually a very easy and simple process. Once the differential is available to access, the SRD, with wench and cable, is affixed to the truck frame in front of the differential and held in place by two adjustable/moveable clamps. Remove differential bolts three and nine, replace with SRD long guide, and support safety studs. Remove the rest of the differential bolts holding the differential to the housing, break the seal and re-insert bolt at 12 o’clock. Attach the SRD winch hook to the bolt at 12 o’clock and, using the remote, apply tension with the wench. Once it is stable, remove the guide and support safety studs and pendulum the differential out and then down to a dolly and roll away. To place in a new or repaired differential, the process is the reverse of the above removal process.