Honda - Genuine Honda OEM Manual Transmission Input Shaft/Mainshaft Bearing | 91004-P21-003 (28x72x18)

Name: Honda - Genuine Honda OEM Manual Transmission Input Shaft/Mainshaft Bearing | 91004-P21-003 (28x72x18)
Brand: Honda
SKU: 91004-P21-003
Price: 116.12 USD
Availability: InStock

SKU:91004-P21-003

Category: Bearings
Vendor: Honda

$116.12

Sale Sold out

Shipping calculated at checkout.

Call for Availability

Quantity

Honda part 91004-P21-003 is a 28 × 72 × 18 mm angular ball bearing used on the manual transmission mainshaft (input shaft). It supports the mainshaft as it rotates inside the transmission and is an important component to inspect or replace during a gearbox rebuild.

Why This Bearing Matters

The transmission mainshaft receives rotational power from the engine through the clutch. Its bearings must support the shaft accurately while allowing it to rotate smoothly at high speed.

A worn mainshaft bearing can contribute to bearing noise, roughness, excessive shaft movement, or transmission-related vibration. When rebuilding a transmission, replacing a questionable bearing with the correct Genuine Honda component can help restore proper shaft support and smooth operation.

Great Choice for Transmission Rebuilds

If you’re already opening a B-Series manual transmission, this is one of those components worth inspecting carefully. Using a Genuine Honda bearing gives you the correct factory dimensions and fitment rather than taking chances with an unknown generic replacement.

Product Details

Brand: Genuine Honda OEM
Part Number: 91004-P21-003
Part Type: Angular Ball Bearing
Location: Manual Transmission Mainshaft / Input Shaft
Dimensions: 28 × 72 × 18 mm
Condition: New
Quantity: 1 Bearing
Application: Manual Transmission
Fitment Type: Direct Replacement for applicable transmissions

Popular Applications

This bearing is found in select Honda and Acura manual transmissions, including applications for the Honda Civic Si, Civic del Sol VTEC, Acura Integra and other compatible B-Series transmission applications.

Exact compatibility varies by year, model and transmission.

Rebuilding your Honda transmission? Don’t overlook the mainshaft bearings. This Genuine Honda OEM angular ball bearing provides the factory-spec fit and dimensions needed to properly support the transmission mainshaft—an excellent choice for OEM-quality transmission rebuilds, restorations and performance builds.

Fitment Notice

Please verify part number 91004-P21-003 before ordering. Honda and Acura used different bearings depending on the exact transmission, year and application. Matching the OEM part number or verifying fitment by VIN/transmission code is recommended.

LOCATION: BIN B-49

Vehicle Fitment

1992-2001 Acura Integra
1999-2000 Honda Civic
1994-1997 Honda Del Sol

Shipping & Delivery

We can ship to virtually any address in the world. Note that there are restrictions on some products, and some products cannot be shipped to international destinations. For international orders, please Contact Us. If you select US shipping rates and are shipping internationally, please be advised you will be contacted to compensate the difference in shipping fees.

Processing takes about 3 to 5 business days before your order ships. We do not process or ship orders on weekends. If you order an item that's on backorder, we will reach out with an estimated arrival time. If you have any questions about shipping make sure to email us at sales@onlinetsm.com or call our reps today at 732-638-5268.

If by any chance, your package that has been delivered by the carrier is lost/stolen, YOU (THE BUYER) are responsible for working with the carrier and us, Tri-State Motorsports to recover your package. You must contact us and the shipping company within 48 hours of delivery for lost/damage claims. You are covered by the basic insurance amount APPROVED by the shipping center. We DO NOT refund or reship product for claims that are denied by the shipping company.

FAQs

When will my product ship out?

Processing takes about 3 to 5 days before your order ships. Some orders may take longer than usual to process and ship. If you order an item that's on backorder, we will reach out with an estimated arrival time. Refunds are subject to a 20% restocking fee. Cancellations are subject to 10% cancellation/processing fee under no exceptions.

What's the Warranty on our products?

Unless the product is manufactured by Tri-State Motorsports or TSM Race, ALL Warranties go through the Manufacturer directly. Please visit their official website and get in contact with them in regards to your warranty. We will supply you with any invoice or tracking information the manufacturer asks you for.

Do you offer any promotions?

One of our major promotions is the TSM Bucks Loyalty Program. You will earn 1 TSM point for every dollar you spend with us. These points can be redeemed for rewards when you reach certain thresholds.

TSM Bucks Info

If you subscribe to marketing emails, you will be given a discount code for 5% off your order that you can use at any time. Our Instagram page also has a variety of weekly promotions in our stories and posts. Some restrictions may apply depending on MAP policies.

What payment methods are accepted?

Tri-State Motorsports accepts American Express, Discover, Mastercard, and Visa. You can also pay over time with Affirm and Klarna. Express checkout methods include: