GM-52086 is used to compress the A-clutch return spring, allowing for the removal and installation of the clutch retaining ring. It is used with the GRE transmission adjustable compressor bridge GM-51892. The adjustability of GM-51892 allows it to expand sufficiently to contact the spring while preventing the spring from flexing and causing damage. GM-52086 contacts the entire perimeter of the spring to compress it evenly.