When the weather is hot, the windows on my 500SL (mostly the driver's side)
seem to be so sticky that sometimes it makes it impossible that I raise it
up completely, even if I leave the engine running for more battery power.
When the car is cooled it will go up easily. Those windows go down and up
every time I put the softtop down.

I suspect the carwash use products that produce this annoyance.

Is there a trick or product that would help without dirtying the windows?

Thanks for any tip or solution.