Gearbox Insider started because the best transmission knowledge was locked inside shops that didn’t share it. That changes here.
Dave is a drivetrain professional based in Ohio with over 15 years of hands-on experience in transmission diagnostics, rebuilds, and shop operations. He has worked on everything from daily drivers to fleet vehicles to performance builds.
He’s seen shops lose warranty claims because of missing paperwork. He’s watched fleet accounts walk because a shop couldn’t produce a compliance report. He’s diagnosed transmission issues that $800 scan tools couldn’t catch — and $14 fluid changes that fixed what a shop quoted at $1,100.
Gearbox Insider is his attempt to close that knowledge gap.
The transmission trade has a documentation problem. Most shops are reactive — they record what happened, but they don’t build systems that protect them when things go wrong.
The shops that stay profitable for decades aren’t necessarily the best wrenchers. They’re the ones who treat the business like a science: documented processes, predictive inventory, airtight warranty compliance.
That’s what Gearbox Insider teaches. Not theory — the actual systems we use.
The mission: Give every shop owner, independent tech, and serious DIY enthusiast access to the same systems and knowledge that the most profitable drivetrain operations run on — without having to figure it out the hard way.
Every piece of content on Gearbox Insider comes from real-world experience — not manufacturer marketing materials or generic automotive advice. We cover:
Transmission diagnostics — How to read codes that most scan tools miss. How to diagnose slipping, shudder, delayed engagement, and hard shifts before they become full rebuilds.
Bench stock and inventory — What to keep on hand, how much, when to reorder, and how to negotiate with vendors so you’re not eating emergency shipping costs.
Warranty compliance — The documentation process that protects you when a customer calls back 11 months later with a claim.
Tool recommendations — Honest breakdowns of scan tools, fluid equipment, and shop supplies. No sponsored reviews. Only what we’d actually buy.
Some links on Gearbox Insider are affiliate links, primarily through Amazon Associates. If you buy something through one of our links, we earn a small commission at no extra cost to you.
We only recommend products we have personally used or tested. Our editorial opinions are not influenced by affiliate relationships.
Have a question about your specific drivetrain situation? Want to suggest a topic? Use our contact form or submit your vehicle for a free warranty review.