Pinion Depth Gauge
There are two parts of the car that are referred to as pinions in a car. The first is in the steering system. When referring to the pinion in the steering system, the pinion is part of a rack and pinion system that is essentially responsible for turning your tires. When you turn the steering wheel, you’re turning the pinion gear, which engages the rack and turns the wheels. The second type of pinion gear in the car is in the car’s differential, and that is what pinion depth gauges measure.
The differential is what allows a car to spin its wheels at different speeds. Without a differential, the torque from your engine would be applied to your drive wheels equally, and the wheels would each spin at the same speed. This might not sound like a big deal, but without that ability, a car cannot make turns correctly. When a car makes turns, the wheels on the side that the car is turning to have to move less. If they don’t, then the car will skid, and that creates a very dangerous situation. The differential divides that power and places it according to which tire has the least resistance, avoiding the problem entirely.
The pinion in the car’s differential is an integral part of the differential that meshes with the crown wheel. Pinion depth is the measurement of the distance between the pinion’s nose and middle of the crown gear. The pinion depth gauge is, obviously a tool that measures this. This can also be referred to as a pinion depth measuring tool, or a pinion depth tool. However, usually a pinion depth gauge is a part of a package – a pinion depth setting tool. While the function of this is obvious, it’s the gauge that allows it to work. The measurements needed to set pinion depth are so fine that it’s very hard to set pinion depth without a gauge.
If you’re going to attempt to use a pinion depth gauge, whether just to check the distance, or to change it, you should first know that they can be very, very expensive. The entire package can cost as much as $700 for the best sets, although you may be able to find one that works for your car for less than half the price.
Once you are ready to actually use the tool, here are the general steps you’ll need to take (may vary depending on the tool you’re using):
- You’ll want to take note of any text or numbers placed on the pinion gear. The most of important of this will be the distance that should be between the pinion and the centerline of the ring gear.
- Make sure that the dial is set t zero. You may have to use the calibrating tube to do this. Also, be careful not to get the dial to tight – this can damage it.
- Fasten the tool onto the rear end housing. Confirm that the longest bar is the closest to the pinion.
- Gauge the space between the bearing surface and the floor of the bearing bore. The bore is circular, and you’ll need to make sure the dial is on the deepest part.
Check that you’ve followed these steps correctly. Now, use the pinion depth gauge to find the distance between the pinion and the centerline of the ring gear. You’ll want to do this multiple times to make sure that you have exactly the right measurement. If you’re getting inconsistent results, adjust the position of your tool; you may have to use additional tools to make sure the placement is exactly right.