Leave it to the English to provide a Plastigauge kit with 2 types of grease.

I most recently used it on my 91 Jetta 1.6 IDI diesel where I did a quick and dirty in situ re-ring ( no chassis crossmember to get in the way on VW). I pulled the pan and checked several of big end and main bearings. It's handy stuff and will give you at least a ballpark idea on bearing condition.

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80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)