Pricing methodology

We independently collect asking prices from publicly viewable used auto part listings across online marketplaces and auto recycler storefronts. Collection is fully automated and observational: we record what sellers publicly ask for used OEM parts (engines, transmissions, body panels, lighting, electrical components, and more) the same way a careful shopper comparing prices would, just at scale.

We have no data-sharing agreements, partnerships, or commercial relationships with any marketplace, salvage yard, or seller whose listings may be reflected in our statistics. No seller can pay to influence a price guide, and no marketplace supplies us a feed. That independence is the point: the numbers describe the market, not any participant’s interests.

Raw listings are messy. Each one is normalized into a consistent record: part category, vehicle make, model, model year, fitment variant where stated, seller-reported condition grade, and asking price. Listings that can’t be confidently matched to a part category and vehicle are discarded rather than guessed at.

Prices are recorded part-only. Shipping, core charges, taxes, and installation labor are excluded, both because sellers quote them inconsistently and because the part price is the number you negotiate on.

For every part-and-vehicle combination with enough listings, we publish the low, the high, and, as the headline number, the median asking price. Medians resist distortion: one scrap-value core listed at $50 or one optimistic seller asking triple the market can’t move a median the way they wreck an average.

Where sellers state a condition grade, we also publish grade-level medians (A, B, C, and ungraded), since a low-mileage grade-A engine and a high-mileage grade-C core trade in effectively different markets. Each guide shows its listing count so you can judge how much weight the range deserves. Where data is thin, the guide says “price data updating” instead of showing a number we don’t trust.

Listings are re-collected on a rolling basis, and every vehicle guide displays the date its underlying data was last refreshed. Fast-moving categories such as used engines and transmissions are prioritized. Between refreshes, real-world prices can move, so treat any guide’s date stamp as part of the data.

Part Price Guide is an independent, observational price index. We are not a party to any transaction, we do not broker, buy, or sell parts, and we are not affiliated with, endorsed by, or sponsored by any vehicle manufacturer, marketplace, or salvage network. Make and model names are used for identification only.

All figures are provided “as is,” for informational purposes only. They are not offers, quotes, appraisals, or guarantees of price or availability, and we accept no responsibility for decisions made, or losses incurred, in reliance on them. Always verify current prices, condition, and fitment directly with the seller before buying, selling, quoting, or settling a claim. See our disclaimer and terms & conditions for the full legal picture.

Spotted something that looks wrong? Tell us. Corrections make the index better for everyone.