None of the 4 GMC Master Parts Books (covering 1939-1960) that I have show an oil slinger at the front end of the crankshaft of any 228, 236,248,256,270 or 302 GMC inline 6. My 302 doesn't have one.
There is an oil slinger at the rear of the crankshaft between rear main bearing and the rear main seal. The cavity that the slinger rides in has a drain hole in the bottom. This slinger is not removable from the crankshaft. It is machined from the raw crankshaft casting.
Either the slinger you are worried about is a part specific to the Thickstun timing cover you have or one of your buddies dropped a slinger from some other engine in amongst your GMC parts as a prank.
Last edited by Bill Hanlon; 07/01/2026 1:17 PM.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
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