How to Avoid Transmission and Differential Case Damage
Subaru offers a helpful tip to avoid damaging transmission and front differential cases. Avoid over-torquing fill/drain plugs, and never use a power tool for removal or installation of these plugs.
Tighten all fill/drain plugs with a short 3/8” torque wrench only and ensure that the correct torque for the specific application is adhered to. Testing has shown that as little as 15% additional force can strip the case. Once stripped, the case can crack when the stripped threads bunch up on one another while continuing to turn the plug.
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Information courtesy of Mitchell 1
Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.
Mike MavrigianMike Mavrigian
Motor Age Editor
Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety of specialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.
