I don't have an engine manual at my fingertips, but a traction motor M.I. calls out Threadtex 2303 as a thread lubricant. It looks to have been created for drill pipe. I found this with a Google search:
http://www.texacoaruba.com/Texaco/Produ ... #Threadtex" onclick="window.open(this.href);return false;
"Code 2303 Threadtex
Threadtex is a lithium soap grease containing sufficient zinc and talc to provide protection for threads during drilling operations.
Product Application
Threadtex is used primarily on the threads of rotary shouldered connections in drill pipe and drill collars. It helps prevent galling during make-up and is an effective thread sealant under high temperatures and pressures. It is particularly suited for deep well drilling.
Product Description and Features
Threadtex is a lithium soap grease containing zinc and talc. It is easy to apply, offers good coverage and has excellent adhesion. The high level of solids enables Threadtex to provide anti-seizing capabilities, helps reduce friction, prevents galling and resists water washout. Threadtex helps minimize rusting of the pipe threads during storage.
Benefits
In service Threadtex provides:
Protection against galling during make-up
Resistance to water washout
Enhanced field application over a wide temperature range"
Dave