About this part
What it does. Dayco POLY RIB BELT, DAYCO Dayco 311-5030295 drives engine accessories such as the alternator, water pump and air-conditioning compressor.
Symptoms that point to this part
- Squealing on cold start
- Visible cracking or glazing
- Accessories losing power
Fitment. Catalogued as fitting 2025 Lexus Tx550h, 2020–2025 Lexus Ls500h, 2019–2020 Lexus Lc500h. Engine, sub-model and trim can narrow fitment further, so check those attributes on the listing before ordering.