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5.29 4 Cyl Zip Air Locker 29-Spline

Limited Stock!
Fully Built 29-Spline 3rd Members

Fully built 29-Spline 3rd members using all new parts and ready to drop into your axle.  Third members feature top quality high-strength 29-spline ring & pinion gears and your choice of lockers.  V6 units feature larger OEM style V6 gear sets with longer pinion gear.  Each unit is setup with solid pinion spacers for long gear life.  Trail-Safe 29-spline pinion seal provided at no extra charge.  Quadruple-drilled flange covers most Pickup/4Runner and Tacoma driveshaft patterns.

Housing Ratio Spool Detroit ARB Grizzly Zip
4Cyl 4.88 304113-1-KIT 304115-1-KIT 304117-1-KIT 304119-1-KIT 304121-1-KIT
4Cyl 5.29 304114-1-KIT 304116-1-KIT 304118-1-KIT 304120-1-KIT 304122-1-KIT
V6 4.88 304098-1-KIT 304100-1-KIT 304102-1-KIT 304104-1-KIT 304106-1-KIT
V6 5.29 304099-1-KIT 304101-1-KIT 304103-1-KIT 304105-1-KIT 304107-1-KIT

Application Notes:  Spool lockers should only be used in rear applications.  Spools will be harder on axles than a selectable or automatic locker.  Fully built 3rd members will not fit stock Tacoma or T100 axles.

All new 3rd members require a break-in period to prevent damage from overheating. Any overloading or overheating during this periods can cause the gear oil to break down resulting in ring & pinion failure.
€¢ After installation, drive lightly for 20-30 minutes and then allow the diff to cool for at least two hours.
€¢ Avoid heavy throttle use during the first 500 miles.
€¢ Do not tow a trailer during the first 500 miles.
€¢ Change oil after 500 miles to remove any particles suspended in the oil.
This may seem unnecessary, but it is very easy to damage the differential by loading it before the gear set is completely run in. New ring & pinion gears create excess heat when they are new. This excess heat can damage the heat treatment of the gears.

⚠ WARNING Cancer and Reproductive Harm -

All products carry our 12 Month Limited Warranty. All warranties are limited to the original purchaser and are not transferable to subsequent owners of the product. The warranty period begins on the purchase date. Trail-Gear warrants that it will repair or replace, free of charge, any eligible product which, under normal conditions of use and service, proves to be defective in materials or workmanship. This warranty does not cover any labor costs incurred in diagnosis of defects, removal or reinstallation of a product, nor does it cover any other consequential expenses.

Please read and review our return and warranty requirement document before sending in products.

Warranty Exclusions

Trail-Gear Inc. warranty does not cover, and Trail-Gear Inc. shall not be liable for, any undertaking, representation, or agreements made by dealers or other third parties selling Trail-Gear products, except where such agreements are within the provisions of this Warranty.

Specifically excluded from this warranty are failures caused by lack of maintenance, misuse, negligence, modification, abuse, improper application, crash damage, installation or operation, or failures caused by unauthorized service or use of unauthorized parts.

Additionally excluded from this warranty are parts which are subject to normal wear and tear, such as bushings, fluids, hoses, gaskets, belts, etc. Products not manufactured by Trail-Gear Inc. are excluded from any warranty and shall be handled with the original manufacturer.

All parts used in a competitive racing environment are excluded from this warranty. If, after inspection, a part returned, under any warranty, is deemed to be ineligible for warranty repair or replacement, the part may be repaired or replaced for a discounted cost. Return shipping charges will apply. Any part for which a warranty replacement is sought must be returned to Trail-Gear Inc. before any replacement items can be shipped. All replacement parts shipped before the suspect part has been received and evaluated by Trail-Gear, MUST BE PAID IN FULL. In such a case, after the suspect part has been received and approved for a warranty replacement, the purchase price for the replacement will be refunded.

    To begin your warranty claim:
  • Please contact Trail-Gear Inc. at 559-252-4950 or email [email protected] prior to returning any product under warranty to verify that warranty is still in effect.
  • Products must be shipped back to Trail-Gear Inc. at the expense of the customer.
    Ship all products to:
    5356 E. Pine Avenue
    Fresno, CA 93727.
  • Please place a clearly marked copy of the original invoice inside the package.
  • Please include a short note stating the problem you are experiencing.

If any of the above mentioned policy is not met, the package will be refused or warranty claim denied. By completing the steps above, this will ensure faster processing of your claim so that Trail-Gear can get your product back to you as quickly as possible. All warranties are generally processed within 2-3 business days of Trail-Gear receiving the parts from you. Additional delays may be incurred if product needs additional testing or repairing.

If you are an international customer, please email the warranty department at [email protected] to receive further instruction. International customers may have the option to field destroy an approved warranty to avoid costly return shipping. In this case, any shipping charges for replacement parts will be at the expense of the customer.