Honda K20A2/K20A3 Speedo Drive Gear 41312-PPP-000

Honda K20A2/K20A3 Speedometer Drive Gear - 41312-PPP-000

Your RSX or EP3 Si speedometer bouncing all over the place or just dead? Honda part number 41312-PPP-000 is the speedo drive gear that bolts to your diff inside your transmission. It's the gear that drives your vehicle speed sensor so your speedo knows how fast you're going. When the teeth wear down or strip, your VSS can't read your speed. Your speedometer stops working, bounces around, or reads totally wrong. You'll also get VSS codes because your ECU needs that speed data for fuel and ignition. Fresh gear fixes it all.

Here's What This Gear Does

The speedo drive gear bolts to your differential inside your trans. Your diff spins when your wheels turn. The gear's attached to the diff so it spins at wheel speed. The gear teeth drive a smaller gear that's connected to your vehicle speed sensor. The VSS reads how fast the gear's spinning and sends that to your ECU and speedometer. Your ECU uses speed data for fuel trims and shift logic. Your speedo uses it to show you how fast you're going. The gear ratio's matched to your final drive and tire size so your speedo's accurate. When the gear's worn, the VSS can't get a clean signal and everything quits working.

Why These Gears Get Trashed

The speedo gear's plastic meshing with metal gears, so it wears down over time. Running low on trans fluid or dirty fluid from worn synchros makes it worse. High-mileage transmissions (150k+) usually have some wear on the speedo gear. Sometimes the teeth strip completely if the VSS seizes up. If your speedo's acting weird or you're getting VSS codes, this gear's probably worn. Pull the trans and check it. Worn or stripped teeth mean you're replacing it.

You're Splitting the Case for This

You can't touch this gear without pulling your trans and splitting the case. It's bolted to your diff, which is buried inside the trans. You're pulling the trans, draining it, splitting the case, and unbolting the gear from the diff. If you're already doing a trans rebuild, check this gear and replace it if it's got any wear. If your speedo's your only problem and the trans is fine otherwise, you're probably not tearing the whole thing apart just for this. But if you're in there anyway, swap it.

What You Get

• Honda OEM speedometer drive gear (part number 41312-PPP-000)
• Bolts to differential inside transmission
• Drives vehicle speed sensor (VSS)
• Sends speed data to ECU and speedometer
• Matched to final drive ratio and tire size
• Same gear your trans came with from the factory

Fits Your Car

• 2002-2006 Acura RSX Base
• 2002-2006 Acura RSX Type S
• 2002-2005 Honda Civic Si EP3

Compatible Transmissions

• K20A2
• K20A3
• K20Z1

Note: Before you tear your trans apart, check your VSS and wiring first. A bad sensor or corroded connector's way more common than a stripped gear. You can find the compatible vehicle speed sensor for this speedo gear under 78410-S6M-N01. But if you're already in the trans doing a rebuild, check this gear. Worn or chipped teeth mean replace it. When you're bolting the new gear to the diff, make sure it's tight. Loose gear wears faster and the teeth skip.