BMW builds every current model on a unibody platform, so a patent for a body-on-frame chassis — filed in 2024 and published in Germany in late April 2026 — is worth paying attention to. The document, DE 10 2024 130 768.4, describes a modular, scalable ladder frame designed exclusively for battery-electric powertrains, with no mention of internal-combustion engines anywhere in the text. It surfaces alongside months of speculation about a BMW off-roader codenamed G74, rumored to target the Mercedes-Benz G-Class and Land Rover Defender.
A smarter frame
The patent's engineering logic centers on simplicity. Front and rear cross-members, plus the diagonal bracing elements, are designed to be interchangeable. Wheelbase and track width can be adjusted by cutting the longitudinal beams to length — no retooling the entire platform. That kind of flexibility lets a single architecture underpin vehicles of different sizes, which matters if BMW intends to sell a rugged SUV across global markets with varying wheelbase preferences.
Materials go beyond steel or aluminum. BMW's engineers propose fiber-reinforced plastic (FRP) — including carbon fiber — for the frame's beams. Lighter structural components reduce what engineers call unsprung weight, which improves both efficiency and handling over rough terrain. For an EV hauling a heavy battery pack, every pound saved in the frame helps.
BMW sixth-generation electric motor. Photo: BMW
What it means for the US market
The EV-only architecture is the headline. A ladder-frame electric SUV can deliver instant torque to each wheel independently, with no mechanical locking differentials required — a genuine off-road advantage that Rivian demonstrated with the R1S. BMW's G74 would enter a segment Rivian currently dominates at the premium end, alongside the Jeep Wrangler 4xe plug-in hybrid and the upcoming electric Land Rover Defender.
If the G74 reaches production — a significant if — the 2029–2030 window matters for tariff reasons. Under current IRA Section 30D rules, final assembly in North America is required for the $7,500 EV tax credit. BMW's Spartanburg, South Carolina plant has been floated as a possible production site; offshore assembly would likely price the vehicle out of credit eligibility and add import cost pressure on top.
BMW has not officially confirmed the G74 or any ladder-frame production program. Patents can be defensive filings rather than direct product roadmaps, as BMWBlog notes. Earlier reporting from 2025 suggested the G74 could offer both a plug-in hybrid (PHEV) and full EV drivetrain on BMW's existing CLAR platform — the ladder-frame patent covers only the electric version. The two approaches may not be mutually exclusive.
