Chemical Guys, Foam Cannon Ratios, Dashcam Molds, and Downpipe Costs: A Buyer's FAQ

Some months, I spend more time checking orders than actually ordering. I'm a procurement manager at a 35-person auto repair and detailing company. I've managed our supplies and equipment budget ($180,000 a year) for seven years, negotiated with 40+ vendors, and tracked every order in a cost spreadsheet. The number I care about is total cost of ownership, not sticker price.

The tire-cleaner fail in March 2023 changed how I think about “just buy the cheap one.” We saved $11 a gallon on an off-brand cleaner, then spent two days re-cleaning wheels that looked worse. That's when I started matching products to actual use cases, not just unit price.

Below is the FAQ I wish I had early on. The costs are from our own purchase records; your region and supplier will shift them. The checks, though, are universal.

• Which Chemical Guys products should I stock for a shop?
• Is the tire cleaner Chemical Guys product worth it?
• What is the right Chemical Guys foam cannon soap ratio?
• Where to buy mold for dashcam housing when a camera breaks?
• What does downpipe replacement cost?
• Where can I buy a system reverse camera?

Which Chemical Guys products should I stock for a shop?

Assuming you already have the basics—microfiber towels, buckets, wash mitts, and a pressure washer—the Chemical Guys lineup is worth considering because you can consolidate car care chemicals, brushes, and shop supplies from one supplier. In our shop, the products that earn their shelf space are:

• A pH-neutral car wash soap
• A dedicated tire cleaner Chemical Guys product
• An all-purpose interior cleaner
• A wheel cleaner that handles brake dust

That covers maybe 80% of our daily work. Not every vehicle needs a specialized product, and buying twelve bottles before you have a reliable core is a mistake I made early on. The “prevention over cure” principle applies to inventory too: check what you actually use before you sign a restocking order.

What I'm not saying is that Chemical Guys is the only brand we buy. We use other brands for specific jobs. But for a core cleaning line, the convenience of one supplier matters when you're processing purchase orders.

Is the tire cleaner Chemical Guys product worth it?

Yes, if you're cleaning tires more than once a week—but check the label before you buy. I've tested several tire cleaners over the years. The Chemical Guys tire cleaner works, at least on the broad range of tires we see in our shop. It lifts dirt and brown film without turning the whole bay into a chemical lab.

From our purchase records, we pay about $16 to $25 a gallon depending on the exact formula and packaging. That's more than a generic industrial cleaner, but we end up using less of it because it foams and clings. The number that matters is cost per clean tire, not price per jug. A $25 gallon that cleans 200 tires is cheaper than an $11 gallon that cleans 60.

That said, we only use it on tires—for wheels, we use a different product. The check, before you commit to any tire cleaner, is to test it on a small section first. Ten minutes of testing beats twenty minutes of scrubbing off a streaky residue.

What is the right Chemical Guys foam cannon soap ratio?

For most Chemical Guys foam cannon soaps, I start at 1:10 soap-to-water. That's about 2 oz of soap in a 20 oz foam cannon bottle, then top it off with water. But don't treat that as a universal law. Some of their soap formulas are more concentrated than others, and the foam cannon's own nozzle adjustment changes the final result.

The label on the jug is the real authority. If you're getting thin foam, add a little soap. If the suds are so thick they won't rinse away, back off a bit. The expensive mistake I saw was a new hire filling the bottle almost full with soap because a video said “more soap equals more foam.” It clogged the cannon and took nearly an hour to clean out. Checking the ratio before you fill saves a whole lot of headache—and replacement parts.

Where to buy mold for dashcam housing when a camera breaks?

Let me split that into two cases, because “mold” can mean two different things.

If you mean the plastic trim/surround that holds a dashcam—often called the housing—you can usually buy a replacement from the camera maker, a salvage unit, or an auto electronics vendor. Search by the dashcam model number plus “housing” or “trim.” Don't buy a generic “mold” and try to cut it to fit.

If you mean an actual injection mold to manufacture dashcam housings, that's a production decision. A basic prototype tool can run $3,000 to $15,000 depending on part size, material, and cavity count. Looking back, I should have started with a 3D-printed prototype before pricing tooling for a custom housing. At the time, I was so focused on per-unit cost that I ignored the real upfront cost: the mold itself. If you're fixing one broken camera, a mold is not the solution. If you're launching a product, get three quotes and ask about tool steel, cycle time, and maintenance before signing anything.

What does downpipe replacement cost?

On a standard sedan or small SUV, downpipe replacement cost in our tracked invoices usually lands between $350 and $1,500 including parts and labor. The part itself can be $150 to $900 depending on whether it's a simple exhaust downpipe or a turbocharged car's downpipe, where the flange design, oxygen sensor mounts, and material all matter. Labor is typically $200 to $600 because the job can involve removing heat shields, fighting rusty fasteners, and checking the O2 sensor wiring.

I know that range is not satisfying. Basically, the range is wide because the part is not the whole story. The useful part is the checklist: photograph the old part, verify the part number on the new part, and inspect the flex pipe and hangers before assuming the downpipe is the only issue. Replacing a downpipe when a rusted hanger is the real problem turns a $50 fix into a $900 job. The service manual is the authority for part numbers and torque specs. Five minutes of inspection beats five hours of backtracking.

Where can I buy a system reverse camera?

If you're asking where can I buy a system reverse camera, start with a vendor that sells complete kits, not just a bare camera module. In a B2B purchase, that distinction matters because “system” means the camera plus a display, a power/trigger harness, and the cable run.

We've bought complete kits from dedicated car-electronics wholesalers and from established online marketplaces. The lowest tracked price for a decent 7-inch complete kit was around $90 for a fleet vehicle; the more reliable kit we've used cost about $230. The difference was almost always the harness. Cheap harnesses are the failure point.

Check whether the kit includes a reverse-trigger cable, a monitor bracket, and the right video input adapter. Oh, and if the vehicle already has a factory screen, buy a camera designed for that system rather than a generic kit. Otherwise you'll end up with an extra monitor and a harness you don't need. That's a lesson I learned after returning two “cheap” kits.