Select the year of your Ford Mustang:

Yukon Gear & Axle YA FMUST-4-31
If you're looking to upgrade your Ford Mustang's rear end, the Yukon Gear & Axle YA FMUST-4-31 is an excellent choice. Designed specifically for the 1999-2004 Mustang, this axle kit combines durability with performance, making it a popular option among enthusiasts.
Key Features:
- 31 Spline: This axle features a robust 31 spline design, ensuring it can handle the power demands of your Mustang.
- 5 Lug Configuration: The 5 lug setup provides a secure fitment and compatibility with a wide range of wheels.
- Ford 8.8” Fitment: Specifically designed to fit the Ford 8.8” rear end found in the 1999-2004 Mustang, ensuring a hassle-free installation.
- Complete Kit: The package includes a Dura Grip Positraction unit, carrier bearings and races, carrier shims, axle bearings and seal, and studs, giving you everything you need for a full replacement.
Benefits:
This axle kit not only enhances the performance of your Mustang but also improves its reliability. Whether you're hitting the track or cruising the streets, the Yukon Gear & Axle YA FMUST-4-31 is built to withstand the rigors of both daily driving and spirited performance.
Technical Specifications:
- Material: High-quality alloy for increased strength and durability.
- Heat Treatment: Advanced heat-treating technology ensures the axle can handle stress without compromising integrity.
Customer Feedback:
Many users have reported a noticeable improvement in traction and handling after installing this axle kit. One customer mentioned, "The Dura Grip Positraction really makes a difference; I can feel the power transfer much better during hard acceleration." Another user stated, "Installation was straightforward, and the quality of the components is top-notch. Highly recommend this for anyone looking to upgrade their Mustang's rear end."
Overall, the Yukon Gear & Axle YA FMUST-4-31 is a reliable and high-performance option for Mustang owners looking to enhance their vehicle's capabilities.
⚠ WARNING:
Cancer and Reproductive Harm
https://www.P65Warnings.ca.gov
Make Vehicle | Model | Year |
---|---|---|
1999-2004 Ford Mustang |
Mustang | 1999-2004 |
Upon notification of a warranty claim, Yukon shall investigate the claim of defect, and, in the event of a verified defect, shall, at their sole choice, either repair the defective product, replace it, or refund the purchase price.
This warranty does not cover, and Yukon shall not be liable for, incidental or consequential damages, including loss of time, road service charges, labor charges, inconvenience, loss of vehicle use, loss of revenues, or loss or damage to personal property (including loss or damage to vehicle parts due to the failure of the Yukon product)*. In addition, this warranty does not cover, and Yukon shall not be liable for, any undertaking, representation, or agreements made by dealers or other third parties selling Yukon Gear & Axle products, except where such agreements are within the provisions of this Warranty statement. Also, this warranty does not cover damage to the axle caused by or facilitated by failure of a non-Yukon component.
This agreement offers you specific legal rights. You may also have other rights which vary from state to state.
YUKON WARRANTY BY PRODUCT
Spool
- Length:As long as original purchaser owns vehicle in which Spool is originally installed
- Notes:It is normal for Spools to cause tire chatter, squeal, or scrubbing when vehicle is not moving in a straight line. Both rear tires must measure the same height from ground to top of wheel for Spool to function properly without premature wear.
- Length:As long as original purchaser owns vehicle in which Super Joint is originally installed
- Notes:Warranty coverage is for breakage of cross section or caps only. Failure by wear or galling is not covered.
- Length:One (1) Year
- Notes:Covers parts for one year against manufacturers defects.
- Length:Ten (10) Years
- Notes:Covers parts for ten years against manufacturing defects.
- Length:Ten (10) Years
- Notes:Covers parts for ten years against manufacturing defects.
- Length:Limited Lifetime
- Notes:Limited Lifetime warranty covering manufacturing defects and axle breakage for as long as you own the vehicle. This warranty is not transferable to another party. "No Questions Asked" replacement for first warranty return, however, Yukon reserves the right to either replace axle or refund original purchase price after the first warranty claim. Yukon (through RANDYS Worldwide Automotive) makes final determination on warranty considerations.
- Length:Limited Lifetime
- Notes:Limited Lifetime warranty covering manufacturing defects and axle breakage for as long as you own the vehicle. This warranty is not transferable to another party. "No Questions Asked" replacement for first warranty return, however, Yukon reserves the right to either replace axle or refund original purchase price after the first warranty claim. Yukon (through RANDYS Worldwide Automotive) makes final determination on warranty considerations.
- Length:One (1) Year
- Notes:Warrantied against manufacturing defects for one (1) year.
- Length:One (1) Year
- Notes:Exclusions apply, does not cover premature clutch wear or abuse. It is normal for Positraction differentials to cause tire chatter, squeal, or scrubbing when vehicle is not moving in a straight line. Both rear tires must measure the same height from ground to top of wheel for differential to function properly without premature wear. Limited slip additive or appropriate friction modifier must be used with oil to reduce Positraction chatter.
- Length:Six (6) Years
- Notes:All Zip Lockers come with a six (6) year warranty against manufacturer defect, including any collaterally damaged parts and associated labor, up to $2,000*, for the first two (2) years. Collaterally damaged parts must be submitted for inspection. Receipts for parts and associated labor must be submitted as well. Only claims deemed reasonable by Yukon Gear & Axle will be accepted. Offer may be discontinued without advance notice.
- Length:One (1) Year
- Notes:Covers the replacement of the unit and any collaterally damaged parts and associated labor, up to $2,000. Collaterally damaged parts must be submitted for inspection. Receipts for parts and associated labor must be submitted as well. Only claims deemed reasonable by Yukon Gear & Axle will be accepted. Offer may be discontinued without advance notice.
- Length:One (1) Year
- Notes:Covers parts for one year against manufacturing defects.
- Length:One (1) Year
- Notes:Covers parts for one year against manufacturing defects.
- Length:One (1) Year
- Notes:Covers parts for one year against manufacturing defects.
- Length:One (1) Year
- Notes:Includes BK, MK, PK, and YK. Covers parts for one year against manufacturing defects.
- Length:One (1) Year
- Notes:One year against manufacturing defects. Exclusions apply, does not cover clutch wear in limited slip differentials.
- Length:Limited Lifetime
- Notes:Limited Lifetime warranty covering manufacturing defects and breakage for as long as you own the vehicle. This warranty is not transferable to another party. "No Questions Asked" replacement for first warranty return, however, Yukon reserves the right to either replace the part or refund original purchase price after the first warranty claim. Yukon (through RANDYS Worldwide Automotive) makes final determination on warranty considerations.
- Length:Limited Lifetime
- Notes:Limited Lifetime warranty covering manufacturing defects and breakage for as long as you own the vehicle. This warranty is not transferable to another party. "No Questions Asked" replacement for first warranty return, however, Yukon reserves the right to either replace the part or refund original purchase price after the first warranty claim. Yukon (through RANDYS Worldwide Automotive) makes final determination on warranty considerations
- Length:One (1) Year
- Notes:Warrantied against manufacturing defects for one (1) year. Longer warranty is available through purchase of a Y.E.S. plan.
Installation Instructions
Click to view the Installation Instructions here
Check out these other great products
