Description

Quick Change Gear Set – 8500 Series – Set 21 – 10 Spline – 4.12 Ratios 6.29 / 2.70 – 4.86 Ratios 7.41 / 3.18 – Steel – Polished – Each

Why Choose Us?



Frequently Asked Questions​

As an Authorized Automotive Retailer in the United States, we take pride in guaranteeing 100% authentic products from all brands available on our website. With partnerships spanning 1,000+ brands and a network of 20+ distributor warehouses nationwide, we maintain millions of auto parts in inventory across the USA, ensuring quick shipping and reliable service to our customers. When you shop with us, you're investing in quality and trust.
We believe we have the fastest backorder system in the U.S. auto parts industry, thanks to our strong partnerships with brands and vendors. Nearly all backordered auto parts are shipped directly by the vendors without any additional delays, or they are placed as special orders on the same day. In most cases, backordered parts are delivered within 5-10 days.
We offer unbeatable prices and the best shipping rates on auto parts, with exclusive protection and insurance included to safeguard your order from damage or loss. Enjoy convenient door-to-door delivery, real-time tracking, and our 100% satisfaction guarantee for a smooth, worry-free experience.
Our standard shipping typically takes 1-3 business days. We will provide estimated shipping time for each product. While we aim to deliver as quickly as possible, this timeframe ensures all orders are processed, prepared, and dispatched with care. If the products are not ready for shipping in 72 hours, we will refund you 100%
Absolutely. Once your order is dispatched, you’ll receive an email with tracking details, so you can follow your shipment every step of the way. Every step of shipping process will be sent through email notifications or using tracking page.
Every product page includes a stock level indicator to show what’s available. We always update the inventory 24/24. We’ll be happy to check availability and provide updates on new stock arrivals if you need a help.
We’re sorry to hear that your order wasn’t delivered in perfect condition. Please email us with your order number, a description of the issue, and photographs of the damaged item. Once we receive this information, we’ll arrange for a replacement or refund and handle the return process.
You can return items within 30 days of receipt. Ensure the product is new in its original packaging and securely wrapped for safe transit. Once we receive the item in sellable condition, we’ll issue a full refund for the product value. Contact us for the return address and further instructions.

About WINTERS

For more than 60 years, Winters Performance Products has been producing high-performance rear ends and driveline components for racing and street use. Their product offering includes everything from quick-change gear sets to shifter assemblies, as well as many components specifically for the sprint car market.

International Shipping

Below are estimated rates and delivery times for popular destinations; full carrier options are available at checkout.

Our dedicated team has years of experience managing international logistics and customs documentation to ensure smooth delivery from our US warehouse to your door. Please review our shipping policy and local import regulations before ordering.

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