I have a proflo single handle tub/shower faucet that has a rapid vibarating or motor boat sound when increasing the cold water. The hot water is quiet until you start to add cold. I have replaced the cartridge, made sure not air in the lines. That faucet is the only one that makes a noise. Please, can anyone help. Thanks

Jack, you did exactly what I would have done, replaced the cartridge. Forget about air in the lines, old wives tale. Something is still moving and vibrating, did you grease the new valve with plumbers silicone grease? If not try that before we do something more destructive than we need to

Hi guys

Real quick like, check behind the tub/shower unit and see if there is an access panel. If there is an access panel then it is possible that there are shutoffs behind the access panel.

If you find shutoffs behind the access panel then my guess is that the cold water shutoff has a washer that has become dislodged and you can try to replace the washer or even better... replace the shutoff entirely!

If there is no access panel then try greasing and reinstalling the cartridge as ballengerb1 suggested. Let us know what you discover...

Mark

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