The only thing found related to this is SB-264.
Extraction from SB-264
CH/CV11-16, CV460-495
Valve/lifter noise complaints on Command singles are
usually about lifter clatter right after start-up. Once the
lifters pump back up, usually within 2-3 minutes of run
time, the noise goes away. A recent design change may
help alleviate complaints of this nature.
Beginning in July of 2002, we have been gradually
switching to solid ball push rods on these engines. The
solid ball provides two advantages. By blocking the bleed
hole in the top of the lifter, it retards lifter bleed down
during storage, and it helps keep air from entering the
lifter. The lifter stays pumped up with oil, so there is little
or no noise at start-up.
Two different push rods are used, depending on engine
model. The CH/CV11-16 engines use Part No.
12 411 04-S, and the CV460-495 engines use
12 411 05-S.