12v Cummins – Adjusting Screw

Enhance your 1989-1998 5.9L 12V Cummins with Nitrided Billet Tool Steel Adjusting Screws.

These screws are made from H-13 tool steel, heat treated, triple tempered, and nitrided for durability.

Manufactured with rolled threads and broached for Allen wrench compatibility.

Custom screws available with oil holes or oil grooves upon request.

Stock rocker arm setup uses part number D-828 with stock length, thread pitch, and ball radius.

Proper installation crucial; deviations affect rocker arm ratio and valve lift.

Pre-lubricate with high zinc assembly oil to prevent galling during initial start-up.

Pair with lightweight 12-point poly lock jam nuts for optimal performance.

For D-828 screws, consider our D-851 jam nut for best results.

For further assistance, call (951)245-6565.