Companion Parts Store

Need the part on the bench by tomorrow? Shop gearboxinsider.com.

The same drivetrain pro who writes the diagnostic articles on this site also runs a parts store. Solenoids, sensors, seal kits, rebuild kits, fluids, snap-ring pliers, and bench tools — ready to ship, no parts-store counterman runaround.

Browse the Store → View All Collections
Free shipping over $75
Same-day handling M-F
30-day returns
Tracked USPS / UPS
Shop by Transmission

Find parts for the platform on your lift.

Collections organized by transmission family. Solenoids and sensors at the top, kits and hard parts behind. Click through to the store to filter by part type, OEM number, or vehicle year.

GM

4L60E / 4L65E Parts

Shift solenoids, TCC PWM, input/output speed sensors, sun-shell kits, pump bushings, and full rebuild kits. The bread-and-butter GM platform.

Shop the 4L60E collection →
GM Heavy Duty

4L80E / 4L85E Parts

Heavy-duty solenoids, TCC kits, sprag kits, valve body fixes for the truck-and-tow workhorse. Built for 1991-2009 GM trucks and SUVs.

Shop the 4L80E collection →
GM 6-Speed

6L80 / 6L90 Parts

Solenoid packs, TCM-related sensors, valve body fixes, and shudder-fix kits for 2006+ GM late-model transmissions.

Shop the 6L80 collection →
Cummins / Ram

68RFE / 48RE Parts

Sonnax-grade upgrades, solenoid blocks, accumulator kits, billet input shafts — for the Cummins truck transmissions that take real abuse.

Shop the 68RFE collection →
Ford

Ford 6R80 / 10R80 Parts

Solenoid bodies, pressure sensors, leakage-pin fixes, and valve body rebuild kits for the F-150 / Mustang / Expedition platform.

Shop the 6R80 collection →
Bench Tools

Rebuild & Bench Tools

Snap-ring pliers (HD, long-reach, 4-pc sets), seal installers, torque-angle gauges, noid lights, cooler-line tools, and band-adjustment kits.

Shop bench tools →

Why shops order from Gearbox Insider

No counterman lottery

You aren't gambling on whether the parts-store kid knows the difference between a 4L60E TCC solenoid and a PWM solenoid. The listings are written by someone who's installed thousands.

Tested before listed

We don't list anything we haven't run on the bench or in a customer vehicle. If a brand has comeback issues, it doesn't make the cut.

Direct fulfillment

Most orders ship same business day. Tracked USPS or UPS. 30-day return window if you ordered the wrong part — we'll swap it.

Cross-referenced

Listings include OEM numbers, common aftermarket cross-references, and vehicle-fit notes so you can match against what's on the bench fast.

Real inventory

Stocked items ship from real warehouses, not drop-shipped from overseas. What you order is what arrives, when it says it'll arrive.

Bundle & save

Rebuild kits packaged by transmission family. Bench-stock bundles for the high-turn parts. Less time pulling line-by-line, less risk of missing a part mid-job.

Ready to order?

Browse the full storefront, search by OEM number, or jump straight into the collection for your current job.

Visit gearboxinsider.com →

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