Should You Trust Your Paint With Costco's Microfiber Towels? Here's What Detailers Say
There exists this strange haven where you can buy a kayak, a cake, and a gaming PC all under one roof. Where the air smells faintly of tire rubber and rotisserie chickens. Then you see it — a mountain of bright yellow microfiber towels priced so low, it feels like they're paying you to take them.
The Kirkland Signature 36-pack — practically standard issue for the loyal Costco member. You can use these microfiber towels to clean your home, polish the lenses of your glasses with them, or deploy them as spiller-cleaner-uppers. But their value is matched by the online debate about one crucial application: touching your car's paint. Is using them on your car the ultimate detailing bargain, or are you slowly grinding microscopic scratches into your clear coat for the sake of saving a few bucks? The answer, like most things in the car world, is complicated.
A tale of two fibers
To settle the debate, you have to look at what these yellow squares are made of. The Kirkland towel uses an 80/20 blend of polyester and polyamide. In simple terms, polyester provides the scrubbing power and structure, while the more expensive polyamide brings the softness and absorption. While 80/20 is great for general cleaning, detailing purists will tell you that the "gold standard" for anything touching paint is a plusher, more absorbent 70/30 blend.
Forensic Detailing's Jon Delieu put the Kirkland Signature towels to the test against his favorite high-end microfiber. Using each to buff a small patch of delicate, piano-black B-pillar trim, the results weren't exactly flattering for Costco's finest — the Kirkland towel left micro-scratches, while the other towel with the higher polyamide content finished the job without a mark.
Then there's the density, or Grams per Square Meter (GSM). While Costco doesn't publicly list this spec, the internet hive mind has reverse-engineered it to be around 350 GSM — a solid workhorse weight. The biggest historical flaw, however, was the scratchy stitched edges and a stiff, sewn-in tag that might as well have been made of sandpaper. Costco wised up and made the towels tagless, which was a huge improvement, but those hard-stitched edges remain a point of serious contention.
The community is divided, but strategy is clear
So can you use them on paint? The detailing forums are a polarized on this topic. Their success, however, seems to come with a strict set of rules: use enough lubrication from a good car soap, apply light pressure, and maintain the towels better than you might your own laundry.
On the other side are the purists, who relegate the Kirkland towels to wheels, glass, and getting stains out of interiors. They argue that on softer paint, the towels can cause micro-marring. They're the adjustable wrench of the detailing world — versatile, cheap, and just a little bit wrong for every job.
So yes, you can use them on paint — just like you can use a butter knife to pry open a paint can. It works ... until it doesn't. For most weekend detailers, the Kirkland towels are perfectly fine, especially with good technique and some common sense. But if you're chasing that mirror finish or working on soft paint, maybe reach for the premium stuff. (If you want to see what the right towel — and the right touch — can do, watch how detailing transforms a car into its most perfect self.)
