Honda K20Z1/K24A2 Final Drive Gear 41233-PZF-020

Genuine Honda K20Z1/K24A2 Final Drive Gear (41233-PZF-020)

This is the genuine Honda final drive gear for the K20Z1 and K24A2 transmissions, the ring gear that sets your final drive ratio and transfers power from the transmission to the differential. It's the part you need when you're rebuilding a transmission, replacing a worn or damaged final drive, or installing a limited-slip differential, since an LSD bolts to this ring gear. It fits the ASU5, NSN4, and PNN4 transmissions. Confirm your transmission before ordering, because related K-series transmissions use a different final drive.

Confirm Your Transmission First

The most important thing on this page, because the wrong final drive won't work in your transmission.

This gear (41233-PZF-020) fits the NSN4 transmission (K20Z1), the ASU5 transmission (K24A2), and the PNN4 transmission (2006 Civic Si Coupe). If you're building or rebuilding one of those, this is your final drive.

The 2007-2011 Civic Si is different. It came with the PNN3 transmission, which uses a different final drive gear, the 41233-RPT-010. So if you've got a 07-11 Si or a PNN3 transmission, you need the RPT gear, not this one.

The rule: match the final drive to your actual transmission, not just the chassis, especially on the Civic Si, where the 2006 coupe (PNN4, this gear) and the 2007-2011 (PNN3, the RPT gear) take different final drives. Verify your transmission code before ordering.

What the Final Drive Does

The final drive gear (the ring gear) is the last gear reduction in the transmission, it's what the differential turns, and its ratio sets how engine RPM translates to wheel speed in every gear. It takes all the torque coming through the transmission and sends it to the differential and out to the axles.

You need a new one in a few situations: rebuilding a transmission where the original is worn, replacing a final drive damaged by a failure, or swapping to this ratio. It's also the gear a limited-slip differential mounts to, so an LSD install involves this ring gear directly.

Works With K-Series LSDs

Important if you're building the transmission with a limited-slip differential.

This final drive gear works with K-series limited-slip differentials, the LSD bolts to this ring gear. So if you're installing an LSD into your K20Z1 or K24A2 transmission, this is the compatible final drive, and the two go together as part of building a proper limited-slip setup. An LSD transforms how the car puts power down out of corners, and it mounts to this gear.

You'll Need Fresh Ring Gear Bolts

Don't reuse the old ones.

Whenever the ring gear comes off, for this final drive swap, an LSD install, or a rebuild, you need fresh ring gear bolts. They're torque-to-yield fasteners that stretch when torqued, so they can't be reused reliably. And note: if you're installing an LSD, you need the shouldered ring gear bolts (the higher-torque version), not the standard non-shouldered ones, even if your transmission didn't originally have an LSD. Ten bolts are required, so order a fresh set with this gear.

Fitment

2005-2006 Acura RSX Type-S (K20Z1, NSN4 transmission)
2004-2008 Acura TSX (K24A2, ASU5 transmission)
2006 Honda Civic Si Coupe (PNN4 transmission)

Part number 41233-PZF-020. Not for the 2007-2011 Civic Si (PNN3), which uses the 41233-RPT-010 final drive. Confirm your transmission before ordering.

If you're building or rebuilding a K20Z1 or K24A2 transmission, replacing a worn final drive, or installing an LSD in an RSX Type-S, TSX, or 06 Si Coupe, this is the genuine Honda ring gear for the job. Confirm you've got the NSN4, ASU5, or PNN4 transmission, grab fresh shouldered ring gear bolts (and your LSD if you're adding one), and build the final drive right.