How to Find Your Shift Knob’s Thread Size (Without Removing Anything)

The single most common question before buying an aftermarket shift knob isn't about looks — it's "will this actually thread onto my car?" Here are the three ways to find out, in order of how much work each takes.

What thread size does a manual shifter usually use?

Most manual transmissions in the US and Japan use a 12mm x 1.25 thread, which is why it's the industry-standard size aftermarket knobs are built around. Every Mr Grip resin knob is threaded 12mm x 1.25 and ships with three reducers — 10mm x 1.25, 10mm x 1.50 and 8mm x 1.25 — covering the next most common sizes without buying a separate adapter.

1. Check your old knob first

If your current knob unscrews (most factory and aftermarket knobs do, apart from a small number held on with set screws), look at the threaded stud it came off of. A thread pitch gauge and a set of calipers will give you an exact diameter and pitch reading in under a minute, with nothing removed from the car beyond the knob itself.

2. Look it up by make, model and year

Thread size is determined by the transmission, not the trim level, so it's consistent across a given platform. If you don't want to measure anything, tell us your car's make, model and year before ordering and we'll confirm the correct thread — or tell you honestly if it's outside what our reducers cover.

3. When in doubt, ask before you buy

A knob that doesn't fit the car it was ordered for isn't a great outcome for anyone. If you're not sure, message us with your vehicle details first. We'd rather answer a question up front than sort out a mismatch after the fact.

Once you know your thread

If you're at 12mm x 1.25, 10mm x 1.25, 10mm x 1.50 or 8mm x 1.25, you're covered by every knob in the range straight out of the box — across every size we make, from a low-profile 95mm to a full 254mm show build.