Although few drivers might disagree that a pristine windshield makes driving more pleasant and safer, I believe the saying, "perfection is the enemy of the good," might be appropriate here. I, too, have used many of the excellent suggestions offered above but have found [like in almost all cleaning/maintenance projects] that frequency is the key.

At times unavoidable, don't allow the windshield to get "too dirty." Employing regular cleanings with mfc and a product like Invisible Glass gets you 95% of the way there [with a minimum of effort] which is great in all but the most acute sun angles and night lighting situations. Being semi-retired and having a generous amount of free time, I generally clean my windshield after each outing, a process that takes no more than five minutes.

 

Cars off gas voc's onto the windshield. I have found Gliptone Heavy duty glass cleaner for both inside and out to work best. Microfiber towel usually works best.

 

I'm still wadding up Alfred E. Neuman posters with straight ammonia. They're good for more than just wrapping fish!

 

Wow, a lot of enthusiastic suggestions...
I have to give praise to the newspaper method. But I don't think it's very effective anymore. One theory was that the newsprint of the past was made with very natural paper, and the ink that was used in presses back then were default impregnated with a gummy alcohol-like fluid that not only gripped the dirt right off glass, but also made it impossible for germs to cling to your fingers (hence finding a wall-street business man with the flu was very rare). But that was with the newsprint from our grandparents and fathers' time, and I just don't feel today's news"paper" or the ink retains those classic properties nearly as much as back then.

Also, depending on the leather, color and age of your cabin interior, smelly vinegars, and stringent cleaners can drip accidentally, and just a drop could leave a smell or discoloration that's more annoying the the smudges you had on your glass.

I had my front windscreen replaced by the dealership once. The new glass was "spotless clean", but any time it was cold outside, or misty first thing in the morning, these ghostly martian moonlanding rings and circles would show up on the inside of the windscreen---frustrating as hell. It was obviously from whatever suction-clamp mechanical arms they used to lift the glass into position during install.
The glass needed a POLISH. Not a cleaning, or alcohol rub, no chemical fluid. Only a dedicated glass-polish grabs up fine films and residue using a rubbery-like abrasion (much like grandad's newspaper ink did), and leaves bare glass behind. Because it goes on like a paste, not a liquid, and dries for you to easily towel it off, there's no funny smell or drips on your leathers.

I use Griot's Fine Glass Polish, and a terry towel or Microfiber towel to rub it off. Don't bother with any "polish" that says it's also also good on "other" surfaces. A true GLASS polish is gentle enough that its clay ingredients give you that super-gentle rubber-eraser effect on precious glass.

Once your insides are clean, keep them that way by rubbing down each window once a month or so, with a pure clean cotton undershirt (or your kid's balled-up cotton underpants out of the clean drawer---don't let the wife see you steal them). No cleaners on the undershirt---simple DRY cotton on glass. It lifts off all tiny invisible finger imprints and moisture before they congeal into the visible hazy grease marks you're seeing now.

On the outside of my glass I'm willing to use whatever kind of cleaners, waterspot removers, chemicals... On the inside, only the clay-based glass polish twice a year, and the cotton undershirt twice a month.
And spank your wife if you catch her putting her make-up covered fingertips on your glass during your next drive.

 

Hey Steve,

Yes, I feel your frustration with getting the inside of the windshield clean. Back in the day (1950's) we used a product by the name of "Glass Wax". It was popularly used during Christmas time to decorate windows with holiday stencils like snowflakes. It's also the perfect solution for those streaky windshields. Just wipe it on, wait a minute for it to haze and wipe it off. No newspaper and no streaks or foggyness - just perfectly streak free glass! The product can be found on Amazon and believe me when I say, "It definitely cleans glass without streaks!!!

 

I keep all my car care microfiber cloths separate from other laundry and wash them with vinegar in the soap dispenser area. Always use cold or warm water only. They come out clean as a whistle with no residue. I dry the cloths on super low or hang ‘em to dry. No streaks to worry about then. My $.02

 

Same. It is the act of just doing it well that is the issue...and for this car I cover up the dash with a clean beach towel to protect the leather from the cleaner....probably not needed but just me. Invisible glass is good stuff. I go over the window twice even with this as I always miss a tiny spot if I don't that I only see when driving into the sun right after a single pass cleaning....

 

I use industrial wipes.
First, an IPA wipe, then degreasing wipes with vinegar, followed by Bohle glass polish sprayed on the Maxigleam glass towel. Good idea to wear gloves, too, keeps the skin oils away.
I get my equipment from this UK supplier https://www.thewipeshop.co.uk/index.php?cPath=46 but I’m sure similar is available in the US.
Having tried sundry sealants and ended up driving at night and in rain in a blurred mess when they wear out, I now go for chemically clean glass inside and out, using an abrasive (Glaco 99) when the chemicals stop working on the exterior.
On an associated vision theme, I can also recommend the new Zeiss DriveSafe lens coating - it really does reduce oncoming LED headlight glare and improve acuity in bad weather.

 

I've tried a lot of the suggestions that have been made here - thanks everyone for your thoughts and ideas!

Here's what I have found works for me:
1) lay a towel on the dash to protect it from window cleaner and tuck it up as far as possible against the most forward edge
2) spray a liberal amount of window cleaner across the whole surface. I use Invisible Glass, but there are probably other good ones as well. Ensure that 100% of the glass area is thickly covered and rub-in thoroughly with the palm of your hand. This is just like using lots of soap and water in cleaning your hands. The cleaner is there to draw contaminants into the liquid so that it can be absorbed away in the next step.
3) using blue shop towels, do an initial wiping to take the bulk of the liquid away from the glass, then go over it again with a second clean shop towel pressing firmly. I've found that using a triangular glass cleaning tool really helps.
4) using a good clean rag also works well but it must have been laundered using laundry soap that is free of scents and fabric softeners - otherwise you'll get a greasy film.
5) do all of this outside as you'll need very bright light to ensure that you get the window completely clean.
6) repeat for the exterior glass surface

This worked well for me. Hope this works for you and thanks for the suggestions everyone!
steve

 

You folks are making this way too complicated. Back in the day (1950's) we used a product by the name of "Glass Wax". It was popularly used during Christmas time to decorate windows with holiday stencils like snowflakes. It's also the perfect solution for those streaky windshields. Just wipe it on, wait a minute for it to haze and wipe it off with microfiber cloth. No newspaper and no streaks or fogginess - just perfectly streak free glass! The product can be found on Amazon and believe me when I say, "It definitely cleans glass without streaks!!!

 

81 corvette ???? had an 80 the only good thing about that car was that i traded it for a 63 split window

 

I took Dwight's advice and purchased the Invisible Glass tool and it has been great. I have done all three of my cars. It's, efficient, and a super easy tool to use that saves my back from all kinds of bends and twists and more importantly it really works. I got it a Lowe's, a bit cheaper than Amazon and the Invisible glass cleaner was also a few dollars cheaper than at my auto store. Thank you Dwight.

 

Yes the two best glass cleaners that I have used are Stoner-Invisible Glass which has been mentioned. I also like Sprayway glass cleaner as well.
I usually have to do multiple cleanings to get the glass really clean!
.
.
.

 

Sorry another false urban legend. Glass is 100% impervious to Ammonia.
Yes it can remove the plastic film window tint. It can not damage glass that is actually tinted.
.
.
.

 

 

Before beginning to wipe your car's inside windshield, first cover the dashboard and any other nearby surfaces with some newspapers. This straightforward step will prevent the homemade solution from damaging the surface of other components within the car. Never undervalue the significance of this small step; it will shield you from additional difficulties in the future.