B&M Automatic Transmission Dipstick

B&M Locking Automatic Transmission Dipsticks

Modern automatic transmissions on trucks and SUVs often ship from the factory as "sealed" units — no traditional dipstick, no accessible fill port, and no easy way for the owner to verify fluid level or condition without a dealer visit. B&M set out to fix that problem with their line of Locking Automatic Transmission Dipsticks, giving drivers a practical, permanent solution for routine fluid monitoring right from the engine bay.

Purpose-Built for Today's Sealed Transmissions

The B&M Locking Transmission Dipstick was designed to allow for a quick and easy check of the automatic transmission fluid level and fluid quality by the vehicle owner or operator without having to go to the dealership. Rather than a temporary service tool, this is a permanent installation — constructed of billet stainless steel fittings, steel braided hose, and black mil-spec anodized aluminum 6061-T6 cap and bracket, this rugged unit allows for both cold and warm fluid level checks and is meant to be installed in the vehicle and locked into place.

This rugged unit replaces the factory plug on the transmission and mounts in the engine compartment for easy routine service checks. The cap screws into the tube and is O-ring sealed, while the base of the tube has a sealing grommet where it goes into the transmission, the same as most new GM transmissions. This design ensures a leak-free, secure fit that holds up to the heat and vibration of real-world driving.

Premium Materials and Thoughtful Details

B&M doesn't cut corners on materials. Features include billet aluminum fittings, stainless steel braided tube, and black mil-spec anodized aluminum 6061-T6 locking cap and bracket. The attention to detail extends to the user experience as well — additional features include a billet locking cap with a "sure-grip" knurled finish for easy handling and the B&M logo milled in the top of the cap.

Some variants in the B&M dipstick lineup go even further. Additional features on select models include an engraved B&M logo locking knurled handle cap and temperature range engraved indicator end, making it easy to distinguish between a cold check and a fully warm operating-temperature reading — critical for getting an accurate fluid level reading on most modern automatics.

Broad Vehicle Coverage

B&M offers dipstick fitments across both Ford and GM platforms. Ford applications include 2010–2023 F-150 trucks with the 6R80, 10R80, 4R70E, and 4R75E transmissions. On the GM side, fitments include 2015–2021 GM 1500 series trucks, 2015–2017 GM SUVs with 8L90E 8-speed transmissions, and 2017–2021 GM Colorado and GMC Canyon trucks with the 8L45E 8-speed automatic transmission. There are also Mopar-focused offerings — the B&M NAG-1 Locking Transmission Dipstick fits NAG-1 transmissions with the 5.7L engine — making B&M one of the most broadly compatible brands in this category.

Whether you're a daily driver who simply wants to keep tabs on transmission health between service intervals, or a performance enthusiast who monitors every fluid in the vehicle, explore the full range of automatic transmission dipsticks and find the B&M part engineered for your specific transmission. Visit the complete B&M brand page to discover the full ecosystem of drivetrain products that complement these dipsticks.