Smear Campaign: How Do You Get Armor-All Off A Windshield?

Posted by

Over at the Car Talk Communities,┬ámember “gudenteit” has a greasy problem he’s looking to solve, after his granddaughter tried to help clean his windshield:

He writes:

“My granddaughter was doing an inside/outside cleaning job on my car a while back. She must have thought that Armor All-type preservative would be a good thing on the windshield! So now when it rains, especially when even only a bit chilly, the wipers smear, which impedes vision, especially at night. I’ve tried different solvents on the glass in addition to Windex; paint thinner, alcohol, acetone, gumout, lacquer thinner, even rain-X. I’ve even cleaned off the wipers with lacquer thinner.

There was no improvement at all. I hired a professional waterless chemical solution car cleaning guy, who used some sort of cleaner on it which didn’t help a bit either. I think maybe the rain-X even made it a bit worse, since it seems to be a petroleum base? Other than a new windshield, is there anything I could do? Would pumice help or worsen the smear?”

Search for Your Next Car at

Crowdsourced solutions in the community were all pretty good:

armor-all-glass-2 armor-all-glass-1armor-all-glass-3

But at this point, we’re all just guessing what might work.

The first step in fixing the issue is to figure out what the heck is in Armor All to begin with. A quick Google search reveals the official .pdf of the Safety Data Sheet that Armor All/STP Products is required to have on file by the Occupational Safety and Health Administration, so that employees can know about potentially harmful substances in the workplace. It’s also required for local fire departments and emergency planning officials under Section 311 of the Emergency Planning and Community Right to Know Act.

Search for Your Next Car at

It basically lists the potentially harmful active ingredients in a product like Armor All. According to the SDS, Armor All includes:


Given that the boiling point listed on the SDS is 212 degrees, the bulk of non-hazardous ingredients are probably water, with some fragrance and inert materials tossed in for good measure. The active ingredient here — and the one that’s probably causing the bulk of the smear on gudenteit’s windsheld — is mineral oil.

Mineral oil is a liquid by-product of refining crude oil to make gasoline and other petroleum products. Cleaning it off requires an organic solvent strong enough to float the mineral oil residue off the glass.

A little personal history: Before I took a gig as a writer, I spent a few years as an installer at a glass shop near Boston. Prior to installation, windshields are subjected to all kinds of things that would leave a customer dissatisfied if you didn’t clean them off. Fingerprints, oily residues, dust, airborne contaminants and all kinds of nastiness need to be cleaned off prior to installation, and then again after the installation is complete.

Search for Your Next Car at

We’d typically use heavy duty glass cleaner, the primary active ingredient of which is usually alcohol to polish a windshield to gleaming. But we’d also have to break out the big guns to clean off heavily greasy windshields. For that, we used Crest Industries Release-All. It’s a heavy-duty spray solvent that’s specifically designed to clean up butyl windshield adhesive. If you don’t clean that stuff up quickly, it has a half-life about the same as whatever’s still floating around Chernobyl.

Trouble is, Release-All is pretty hard to find, and if you can find it, you’ll have to buy it by the case, so let’s try and come up with a suitable substitute.

You’ll have a lot better shot at finding a degreaser like CRC’s degreasers at your local hardware or parts store. There are several different varieties, from Quick Clean to Super Degreaser, but they all have the same basic active ingredient:

Tetrachloroethylene is a superior solvent for organic materials. Its the chemical that’s widely used by dry cleaners, and it’s also the primary degreaser for the automotive and metalworking industries. CRC’s Heavy Duty Degreaser uses it as the primary ingredient, and you can find it in any decent auto parts store.

A few tips for using it:

  • Tetracholorethylene is pretty nasty stuff, so wear gloves and use it in a well-ventilated place.
  • Since you want to clean the inside of the windshield as well as the outside, you don’t want chemicals spraying all over the dashboard. A chemical like this can damage or discolor plastics, so spray it on a paper towel or a microfiber cloth first and then use that to wipe the glass clean.
  • Heavy Duty Degreaser isn’t a glass cleaner, so follow that up with a good glass cleaner. The best glass cleaner known to man is Sprayway. It not only cleans glass to a completely transparent shine, but you could do a lot worse than applying its lovely scent as a cologne.
  • Instead of wiping off the glass cleaner with paper towels or microfiber towels, try using newspaper. It’s not absorbent, so don’t overuse the glass cleaner, but newspaper polishes glass to an outrageous shine. Just keep it away from fabric trim on the A-pillars and headliner because the ink could stain it.

I’d be surprised if cleaning the windshield with CRC Heavy Duty Degreaser didn’t solve the problem, but there’s one more solution that I haven’t tried that others claim offers great results. Permatex offers a product called No Touch Auto Glass Stripper. The link to the left is to Permatex’s Australian site, but you can buy it on Amazon here in the U.S. According to the site, it’s “a heavy-duty cleaner specially formulated for auto windshields. It removes silicone build-up, hard water stains, mud, oil, bugs, and tar that other cleaners cannot.” It’s worth a shot.

Finally, there’s a great windshield cleaning tutorial for the truly obsessive at They recommend how to clean the inside of a windshield that’s covered in years of cigarette smoke.

The last concern is the wiper blades. For less than $25, chuck the inserts in the trash and spring for some new ones. They probably need to be changed anyway.

Search for Your Next Car at

After you get it cleaned up, give your granddaughter a hug for being such a good, helpful kid and let us know how you made out.

Craig Fitzgerald

Craig Fitzgerald

Writer, editor, lousy guitar player, dad. Content Marketing and Publication Manager at