Belt Set 78-1341 78-603 78-629 – Fleet Supply for Thermo King SB
Belt Set 78-1341 78-603 78-629 – Thermo King SB Series, 3-Piece Drive Belt Kit — includes alternator belt (78-1341), fan belt (78-603), and engine/idler belt (78-629) for SB 100 through SB 400 and Spectrum DE refrigeration units. Replacing all three belts as a matched set at scheduled intervals prevents staggered failures and cumulative downtime across cold-chain fleets Progressive wear signs — cracking, glazing, rib separation — typically appear as operating hours accumulate in continuous refrigeration duty Replacement interval recommendations ship with each order to support long-term fleet maintenance planning.