Sizing your RockNob

RockNob Shift Lift Sizing Instructions

We want your RockNob Shift Lift to fit your stick threads exactly. Read the information on this page carefully and you should have no problem sizing your RockNob Shift Lift.

There is no industry standard for gear shift knob thread sizes. However, most cars fall into groups of a few US standard threads, and metric threads. See the quick tutorial below on how to read thread notation.

We currently don't make "press-on" RockNobs. "If you can't unscrew it, we don't do it".

TUTORIAL ON THREAD SIZE NOTATION

Before getting too deep into thread sizes here is a quick tutorial on how to read thread notations.

For US Standard threads the first number, or fraction, is the thread diameter in inches. The second number, separated from the first by an "X" or a dash, is how many threads can be counted in an inch. Example: "3/8 X 16" means 3/8 in diameter, 16 threads per inch. Similarly for Metric threads the first number is the diameter in millimeters (mm), and the second is the distance between threads in mm (NOT number of threads per mm). So, as a bonus, you now are an expert on threads...and all you just wanted to do was buy a Shift Lift!

Detailed below are a number of ways that you can determine the thread size needed for your car.

DETERMINING THE THREAD SIZE YOU NEED

Use a metal thread gage and diameter template to determine the correct thread size for your vehicle. Metal thread gages are generally a set of thin pieces of metal with teeth on them. These can be found at machine shops, car mechanics, and sometimes hanging on a wire near the "nut and bolt" aisle of a hardware store.
Go to a hardware store with your current gear-shift knob in hand and find a bolt that screws nicely into it then read off the bin what its thread size and diameter are. Be careful not to strip the threads in your knob by forcing a fit, it should go in as easily as it screws onto your stick.

So, now that you have determined the correct thread size for your vehicle you can now enter it or select it in the order form for new Shift Lift...whew!