How to Identify a T&D rocker arm
The fastest way to identify T&D rocker arms is the shaft diameter and adjuster screw size. While most other shaft rocker brands use 3/8″ (.375) adjusters, the majority of T&D rocker arm’s will be a larger 5/8″ (.625) – 7/16″ (.4375) diameter – less applications where valve cover clearance is a factor.
T&D rockers (with the exception of our sport comp line) are also internally oiled. This means rocker arms will have oil holes drilled internally in the rocker body, which are visible behind the roller tip in the body itself.
T&D rockers production date, ratio, fulcrum length and offset codes are stamped on the rocker body itself.
Ratio: Letter stamped near the adjuster screw. Code key is as follows;
Fulcrum Length: 1st of two numbers stamped under the ratio code near the adjuster screw. Newer rocker assemblies only.
Offset: 2nd of two numbers stamped under the ratio code near the adjuster screw. Newer rocker assemblies only.
Date code: 6 digit code stamped on the side of the rocker arm.
“F” = 1.70 ratio “090204” = production date September 2nd 2004
“H” = 1.80 ratio “4” = 1.640″ fulcrum length “1” = center offset
“042414” = production date April 24th 2014