My old drive belt was sqeeking so i replaced it. The new belt does not squeak but it keeps slipping off. But when I put the old one back on it does not slide off. Why is this? I replaced tensioner and idler pulleys but new belt still slips off. The old one still stays on. Car is 97 jeep grand cherokee. 5.2L
My car has an automatic transmission.
Check to be sure that the new belt is actually the right part number or, better yet, use an OEM (dealer) belt. Also, be sure the tensioner is the right part number or use an OEM sourced tensioner. Check to be sure that all of the pulleys and accessories (e.g., alternator, water pump, A/C compressor) that are driven by the serpentine belt are all operating in the same plane. It is not unusual for the pulley on the crankshaft harmonic balancer pulley to move (generally outward) relative to its original position. The pulley is rubber bonded and over time can move. If that pulley moves, that means that the belt groves are no longer running in a perfect plane and that alone can cause slipping. If you request serpentine belt inspection a certified Mechanic, dispatched by YourMechanic right to your location, will identify the problem and thence get the issue resolved for you promptly. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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