Recently the tinting on my windscreen started smudging. 3M C70. Had it on for close to 2 years.

Went to applicator and was told the adhesive started melting. Was replaced with no questions asked. It's not the first time in the household, another car had this issue too with the windscreen.

I am surprised that 3M C70 has this issue. I had been told that using a windscreen sunshield, will accelerate this phenomena.

Do most of you still use sunshield for windscreen eventhough have C70 applied?

Years back when cars at home had V-Kool, never had such issues.