A fluid meant for the temperatures the van will be exposed to. I run regular blue -20 rated fluid and it works great. I avoid the stuff with ice melt, bug vaporize, and rain anti-gravity in it....leaves gross stuff in the tank (especially on heated ones) and can make the wipers skitter on the glass.
Thank you all for your help with this. I just got some wash from Wallyworld. It seems to work great! I was concerned about the heater gumming up the system, I guess it's not a problem.
This forum is great!
Yeah, typical washer fluid you find at autoparts stores and gas stations (at least in west mountain states) is 50% distilled water (important that it's mineral-free), 50% methanol, plus trace amount of blue dye. That's just going to boil off worst case. MB stuff seems to have some detergent added too, which probably helps clean the bugs.
I just took my wife's 2017 Metris in for it's last free "B" service. It's her's, I don't drive it much...so on my way out the door she says the front wiper fluid is barely coming out. I check them and yep, just a trickle. When I'm checking in with the Service Manager, I ask if they could look into it. He says, "Have you filled the reservoir?". "Yes", says I. "With what?" says he. "RainX" I reply. "What color?" he inquires. I said, "Orange". He quips, "Well that's the problem and it's not covered under warranty". I said leave it and I'll fix it. I'm thinking BS. I've used RainX (and others) for years in all my vehicles and RainX has never clogged anything up. Now, I'm on really good terms with the Tech who works on the vans. I field the problem and what the SM told me to him. He says the orange and green RainX is a vinegar formula and it reacts to an "additive" in the MB fluid that causes the fluid to gel and clogs the mesh screen and nozzles. I've seen similar with mixing anti-freezes so in my pea size brain he explanation has plausibilities. Tech says use the cheap "blue" stuff that is alcohol based and I won't have the problem. My demented mind thinks MB puts the "additive" in to cause this problem to get more $$$ out of me. Not really. I'm not that paranoid. Anyway, Tech cleans the system out for me gratis on the QT. When you take care of your Tech...he takes care of you. Here's the picture he took of a nozzle with the goo.
I love Rain-X (orange). Last car I had I siphoned all the factory fluid out and filled it up completely with Rain-X. After a quart or so at speeds of over 50 mph the water runs off so fast you don’t need the wipers, especially at highway speeds. I’m hoping this is true of the Metris when it finally gets delivered.