GM Scrap Catalytic Converter Prices: Class, Serial and Payout Guide

As of 21 August 2026, a Large GM catalytic converter pays roughly $80 to $286 depending on who is buying, with most honest yards landing near $150–$200. Medium GM units run about $100–$192, and low-grade GM units drop to $55–$65. The spread is not a typo — buyer quotes on the exact same converter class differ by more than three to one right now, and knowing that is worth more than any single number on this page.

Current GM converter prices by class

GM converters get bucketed by class rather than by vehicle. The classes below are what buyers actually quote against. Where two sources disagree, both numbers are shown rather than blended into a fake average.

Read the Small GM row carefully. That $18 to $772 span is not a mistake either. Small GM is a catch-all bucket, and a few dense, loaded units get dumped into it alongside genuinely cheap ones. If a buyer offers you $18 on a small GM cat without reading the serial, they are pricing the bucket, not the part.

Why the quotes disagree by three to one

Four things drive the spread, and none of them are the metal market:

• Stale price pages. The iScrap App Large GM page shows $165 but carries a last-updated stamp over a year old. Rockaway and RRCats both refreshed on 21 August 2026. Check the date before you quote a yard someone else’s number.
• Assay versus eyeball. Buyers who run XRF analysis pay on measured platinum, palladium and rhodium content. Buyers who eyeball the shell pay a flat bucket rate and keep the difference.
• Position in the chain. A repair shop taking a converter off your hands pays up to about $50. A scrapyard pays the bucket rate. A recycler who de-cans and assays pays the top of the range. Every hand it passes through takes a cut.
• Condition grading. Rockaway is explicit that a Large GM must be full of material to grade as Large. If the interior rattles, or it has been burned out or hollowed, it gets reclassified down a grade or two.

Reading GM and AC Delco serial numbers

GM is the easiest domestic manufacturer to identify, and that works in your favour. Roughly 90 percent of GM units carry a stamped code, and GM does not bury it under a secondary heat shield the way some makes do.

Where the number lives

• On one of the corners of the converter body, in a 7 to 10 digit numeric form.
• Stamped or etched into the main heat shield, usually toward the middle of the unit.
• On circular end caps on some units, as an 8 to 10 digit numeric code.

Numbers go dark under road grime and surface rust. Steel wool and a wire brush bring them back. Do not grind — if you erase the stamp you have converted a priced part into an unpriced one, and unpriced always gets the bucket rate.

What the prefixes tell you

GM and AC Delco stamps commonly open with 126, 127, 253 and 255. These are numeric part identifiers, not a value code — a 255 prefix does not automatically pay more than a 126. What the prefix does is let a buyer pull the exact unit from a database and price the real platinum, palladium and rhodium loading instead of guessing from the shell size.

That is the whole practical point. A legible serial is the single biggest lever you control on price. Photograph it, text it to two or three buyers, and let them bid against a known part number.

Which GM units actually pay

Size does not decide value. A physically large converter stuffed with cheap ceramic loses to a compact, densely loaded unit every time. Both Rockaway and iScrap say this outright on their own price pages.

The aftermarket line is the one that catches people out. An aftermarket converter can look identical to an OEM AC Delco unit from three feet away and be worth one fortieth as much. No GM stamp, or a stamp that does not match GM prefix conventions, is your warning. Check before you carry it across the yard.

What the metal market is doing

Converter prices track three metals. All three are up year on year, which is why 2026 quotes are firmer than the trough that followed the 2022 peak.

The two spot figures in each row come from different sources on consecutive days. Both are shown because that gap — roughly 6 percent on platinum — is a fair picture of how loosely quoted these metals are day to day.

One structural note worth understanding. Automakers spent years substituting cheaper platinum in place of palladium and rhodium. Converters built after that switch carry a different metal mix than the 2018–2021 units, which is part of why older GM converters can outpay newer, larger-looking ones. Rhodium at roughly $8,500 an ounce is still the metal that decides whether a converter is a $90 part or a $290 part.

Getting a fair number

Practical rules that hold regardless of where prices sit:

• Never accept a quote given over the phone by vehicle name. Silverado does not mean one converter or one price. Quote by serial.
• Get three quotes minimum. With a documented three-to-one spread between published price lists, one quote tells you nothing.
• Do not cut or hollow anything. A full core holds its grade. An opened one does not.
• Bring proof of ownership. Legitimate buyers require it in most US states now, and the ones that do not are the ones paying the worst rates.
• Sell in lots where you can. Assay-based buyers price volume properly. Single units get bucket rates.
• Check the date on any price list, including this one. Anything over a month old is background reading, not a quote.

Prices move daily. No yard is obliged to honour any published list, and the sources above openly say so. Treat every figure here as a benchmark to negotiate against, not a promise.

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