You really need to replace reservoir. Fluid is moving when you are driving and you cannot see it until you stop. It probably has holes in the seams on the bottom. Just make sure that is all they do and don't let them up sell you further repair.
〉 Answered on Jul 12th, 2014 by Gail Dunn, Owner at Women's Automotive Connection
Sounds like it's time to replace your overflow tank & get the cooling system tested to make sure everything else is ok.
〉 Answered on Jul 12th, 2014 by Gelina Aquilina, Service Advisor / Mechanic at