Corrections and data changes

Last updated: October 19, 2026

Report an error

If you think something on this site or in a report is wrong (a figure, a source, a model year, a part number or a recall), email [email protected]. Please include the page or report ID, what you think is wrong and, if you can, a source. Owners, shops and technicians are all welcome to write in.

Our correction commitment

• We read every error report and reply, normally within 5 business days.
• If we confirm an error, we fix it on the site and in the report data, and we log the change below with its date. We don't quietly edit figures.
• If the error affected a report you bought, we'll reissue the corrected report to you free. You can still ask for a refund under the Terms.
• Where we can't confirm a claim either way, we say so and keep the figure labeled ESTIMATE, or we remove it.

Data change log

• Oct 19, 2026: timing-chain build-date rule corrected. We used to say a car built in March 2015 or later has BMW's revised chain parts. That overstated BMW's documents. BMW's SI B11 02 21 (settlement coverage) covers cars built through February 2015, but its earlier SI B11 03 17 (Rev. 7) lists production dates as late as July 2015 for some models. Builds from March 2015 to each model's latest Rev. 7 date are now shown as uncertain (ask a BMW dealer to check by VIN); later builds and model year 2016+ are shown as "likely revised parts (not confirmed)".
• Oct 19, 2026: source labels split into tiers. The single SOURCED label is replaced by OFFICIAL (NHTSA/BMW), SHOP/RETAILER and FORUM/BLOG, and a figure with several sources shows the weakest one. The timing-chain failure range (50k–100k) is now labeled ESTIMATE on the site, matching the report.
• Oct 19, 2026: timing-chain kit and prices updated. xDrive cars use FCP Euro kit 11318648732KT2, not 11318648732KT (rear-wheel-drive/sDrive). Kit and water-pump prices were re-checked on Oct 19, 2026 and are now dated.
• Oct 19, 2026: VIN checker fixes. Model years with no NHTSA recalls no longer show as a recall-service outage. Known B46/B48 models (for example the 330i, 230i, 430i, 530i and X3/X4 30i) and 2016+ 2.0L BMWs that aren't on our N20 list are now shown as "Not an N20" instead of "Possibly N20". The X5 xDrive40e result now says the paid report doesn't cover it yet.
• Oct 19, 2026: timing-chain mileage analysis added. The home page now shows a timing-chain mileage chart, and reports add a timing-chain page with model-year complaint shares. These figures are computed by RepairAhead from NHTSA's bulk complaint file (NHTSA has not reviewed or endorsed this analysis). BMW bulletin citations now point to the copies posted on NHTSA's site.
• Oct 18, 2026: N20 complaint count corrected from 2,088 to 1,726. NHTSA's complaint search groups some trims together (for example, "X3 xDrive28i" also returns xDrive35i and diesel complaints, and MY2012 "328i" includes cars with the older N52 engine). We decoded each complaint's partial VIN and kept only those that decode to an N20 engine: 1,726 of the original 2,088 (MY2012–2015). The timing-chain, water-pump and fire counts were recalculated the same way.
• Oct 18, 2026: 320i model years corrected to 2013–2016. The VIN checker had accepted a 2012 320i. NHTSA's VIN decoder lists no US 320i for MY2012, so the site and report now cover the 320i for MY2013–2016 only.

Sources for these figures are listed under "Key sources" at the bottom of the home page and in each report.