I'm familiar with the diesel chains, so I'm probably wrong here, but I thought the early chains had the two half-moon circlips; then they were superceded by the one elongated circlip that captured both pins on the master link. MB issued a TSB on those clips in 1984, calling for their return to the factory by December of 1984, and the use of the "peened" master link from 1984 on. (this info was for the 617.951) Is this a return to the previous style for a reason any one knows? or have the gasoline engines been diff.?
The Golden Rule
1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)