I have 1982 300SD with about 250K and a 1987 300SDL with about 400K on original engine. Same problem with each. Get excessive tire wear on inside of rear tires. Have replaced axles, rear wheel bearings, spring seats and installed HD Bilstein shocks. Problem is improved but still get wear inside. Do not carry excess weight in trunk.
Need a solution as expensive tires wear out prematurely.
Many thanks,
Carlo