The U.S. aircraft register, updated daily
Parts

Lwr Seal

No failure report names the lwr seal. 2 FAA approvals let 2 companies make a replacement lwr seal, Seal Dynamics INC holding the most (1).

Approved replacement parts 2 parts manufacturer approvals

A parts manufacturer approval (PMA) lets a company other than the aircraft's maker make a lwr seal and sell it as an approved part for the models named. These are the companies holding such approvals for a lwr seal:

MakerPartReplacesFitsGrantedStatus
Seal Dynamics INCLwr Seal, Outer Duct Seal Instl, Common Nozzle Assy LK88136QASRolls Royce P/N LK88136Rolls Royce RB211-535E4-37, RB211-535E4-B-37,...2014-10-09current
Quest Aviation Supply INCLwr Seal, Outer Duct Seal Instl, Common Nozzle Assy LK88136QASLK88136Rolls Royce RB211-535E4-37, RB211-535E4-B-37,...2012-03-01current

Sources: the FAA's service difficulty reports since 1995 (a report is a part that failed and was fixed, as filed by an airline, repair station or owner; the count shows reporting as much as reliability) and the parts manufacturer approvals in the FAA's Dynamic Regulatory System. The part name is the reporters' and the approval holders' own words, reduced to the first plain words so that spellings meet.