Fan clutches. Not many people notice or even care about them. Except when they don't work. We can get into all the specifics on how they work, etc., but I want to keep this short. Effectively when things heat up, the fan clutch moves fluid chambers to "solidify" the fan into more of a lockup operation so the fan works to move more air. As the coolant heat drops across the radiator, the fan gets looser and slips more, and doesn't work as hard.
Anyway, there are TWO versions of the fan clutch that were used on VIN Y/9 engines across Oldses lineup for 1985. The OJ coded fan clutch and the OL coded fan clutch. Looking backwards, the OJ was used on a bunch of V8 applications in very late 70s up through sometime in January/February of 1985. Exactly when that happened, I don't know. Then the OL code took its place. Now, the parts book shows the latest number of 22049774 which covers OJ or OL in the nomenclature. The OJ itself came under GM p/n 559729.
Here's an OJ.
And the NOS OL one. My gray 85 442 came with an OJ, but my black 85 442 came with an OL.
Anyway, there are TWO versions of the fan clutch that were used on VIN Y/9 engines across Oldses lineup for 1985. The OJ coded fan clutch and the OL coded fan clutch. Looking backwards, the OJ was used on a bunch of V8 applications in very late 70s up through sometime in January/February of 1985. Exactly when that happened, I don't know. Then the OL code took its place. Now, the parts book shows the latest number of 22049774 which covers OJ or OL in the nomenclature. The OJ itself came under GM p/n 559729.
Here's an OJ.
And the NOS OL one. My gray 85 442 came with an OJ, but my black 85 442 came with an OL.
