The serpentine belt drives the alternator, water pump, power steering pump and AC compressor from one belt, so when it fails the vehicle stops charging and cooling at the same time. The belt length depends on which accessories the engine has, which is why two trucks with the same engine can take different belts. We match it from the VIN and the option list.
Why the same engine takes different belts
A vehicle without air conditioning, or with a different power steering setup, runs a shorter belt on a different route. Some engines use two belts. Heavy-duty trucks with a second alternator add another. The VIN and the option label settle it; if the label is gone, the number printed on the old belt does.
Replace the tensioner with the belt
A squeal after a new belt is usually a tensioner with a weak spring or a worn pulley bearing. Tensioners and idler pulleys are inexpensive next to the labor of doing the job twice, and on most engines past 80,000 miles they should go with the belt. We quote the belt, tensioner and idlers as a kit.
Signs the belt is due
Cracks across the ribs, glazing on the rib faces, missing chunks, or a chirp on cold starts. A belt that is fraying at the edge points to a misaligned pulley, often a failing water pump or idler, and replacing the belt alone will not last.
Serpentine Belts & Tensioners by make
- Ford — F-150 and Expedition belt routing changes with the engine and with the presence of a second alternator.
- Chevrolet — 5.3 and 6.0 V8s use one main belt and a separate AC belt on many years.
- Ram and Dodge — Hemi and Pentastar belts differ; Grand Caravan tensioners are a common order.
- Toyota — Tundra 4.7 and 5.7 belts, plus the tensioner pulley kit on the 5.7.
- Mercedes-Benz — C300 and E350 belts with the tensioner; the M272 V6 tensioner is a known failure.
- Honda — Pilot, Odyssey and Accord 3.5 belts and auto-tensioners.
Read before you buy
Serpentine Belts & Tensioners FAQ
No. The serpentine belt is the visible belt at the front of the engine driving the accessories. The timing belt is inside a cover and drives the camshafts; it is a separate, larger job.
Usually. The part number and length are printed on the back. If it has worn off, count the ribs and measure the length, and give us the VIN.
Yes, but we recommend the tensioner and idlers with it on higher-mileage engines, and we quote both ways.