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2008 4x4 Drivetrain Buyer's Guide

Posted in How To on April 1, 2008
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I'm sure we've all heard that something, whether it is an organization, team, or vehicle, is only as strong as its weakest link. every weekend, off-roaders learn this adage the hard way - when their weakest link fails, which is typically an axleshaft, differential, or ring-and-pinion set. These highly detailed yet very fragile components typically give way to heat, pressure, and continued use under extreme conditions.

Having your vehicle's gear ratio and drivetrain built to take into consideration your vehicle's tire size, power rating, and the terrain that you choose to off-road in, not only will allow your vehicle to perform better, but the reduction in wear to some of the other vehicle components will be diminished as well, not to mention that your trail breakdowns will be diminished greatly, too.

This month we showcase some of the most widely used products that address these issues and provide a more satisfying off-road experience and vehicle.

J.E. Reel Toyota Land Cruiser Drivelines
J.E. Reel's Toyota land Cruiser drivelines are custom-made to the exact specifications required for them to be bulletproof. each unit is made of stronger tube stock to resist bends and breaks while scraping along hard rocks. Given an increase in operating angle over the stock item and combined with 1350-series U-joints and a 2-1/2-inch-longer stroke in slip, each driveline will contribute to lower cost of repairs and miles of use.

For more information, contact:J.E. Reel drive line Specialists,(909)

Solid Axle industries heavy-duty Jeep TJ dana 44 Axle
Solid Axle industries' heavy-duty dana 44 replacement axle has been created to withstand bending and breaking and to alleviate those unnecessary repairs from a simple day of off-roading. Utilizing their own engineered dana 44 low pinion housing that features 1/2-inch-wall dom axletubes, each axle is assembled using only the highest quality components on the market, some of which include: ArB, Wilwood, precision Gear, Timken, and Goodridge.

Each axle is hand-assembled to ensure the best quality and workmanship and is inspected and numbered. each axle owner receives complete documentation about their axle, as well as 3 quarts of differential fluid for the initial commissioning of the unit.

For more information, contact:Solid Axle industries,(888)

Stak 4x4 Replace-A-Case
STaK 4x4's replacement transfer case is available for all dana 300 transfer case applications. The replacement version offers any available gear ratio, heavy-duty 32-spline output shafts, a solid billet housing, and the ability to be configured in such a way that it turns the transfer case to a driver-side drop without having to turn the unit upside down.

For more information, contact:STAK 4x4,(915) 584-2400,

Atlas Cable Shifters For Jeep TJ
Specifically designed for the Jeep TJ, these high-quality, heavy-duty shifter cables and assembly allow for easy installation and trouble-free maintenance. Best of all, the assembly is able to fit neatly inside the factory center console with no interference to the driver's leg room.

For more information, contact:Advance Adapters(800) 350-2223,

Tom Wood's "Super-Flex" Universal Joint
The unique offset design of this offset universal joint allows for 10 degrees of additional flexibility as opposed to other conventional universal joints. The "Super-Flex" universal joints are available to fit modi-fied driveshafts and many stock Jeep Wrangler and Grand Cherokee applications.

For more information, contact:Tom Wood's Custom drive Shafts,(801)

OX Locker
By utilizing a positive-locking cable, this manual-locking differential unit, designed by a high-tech aerospace manufacturer, mates the two shafts of an axle together for maximum traction.

Features include a heavy-duty-machined differential cover and hardware to match. The system is available for dana 30, dana 35, dana 44, and dana 60 applications.

For more information, contact:randy's ring & pinion,(888) 296-3129,

Precision Gear Suzuki Samurai Ring-And-Pinion Set
Precision Gear's replacement ringand-pinion gearsets for all '85-'98 Suzuki Samurais allow for the replacement of the factory sets with sets containing a ratio of 5.29 to allow for larger tires without a compromise to the performance of the vehicle.

Each set is built for a seamless oe fit back into the factory pumpkin.

For more information, contact:Precision Gear(734) 946-0524,

Jeep TJ Dana 44 Powerlok Limited-Slip Differential
The dana 44 powerlok limitedslip differential unit provides positive engagement without the push/ pull characteristics of a conventional locking differential; the powerlok is suitable for use in front or rear applications.

The two-piece case construction with four pinion mate spider gears provides for more than double the strength and 75-percent more traction than conventional "open" differentials. each unit is fitted with all-steel clutch plates and unique torque-applying cross-shafts for positive action and long life.

For more information, contact:reider racing, (800) 517-1330,

Eaton Elocker
With the mere push of a button, the eaton elocker System electronically locks both axleshafts for uncompromised off-road traction. The system is compatible with other electronic-controlled systems such as brake-activated traction and stability control. The ability for the vehicle to operate in 2-hi, 4-hi, or 4-lo is retained. Additionally, the system is maintenance-free given that no lube additives are required.

For more information, contact:eaton

Dynatrac Prorock 60 JK Series Axle
Dynatrac's new prorock 60 JK Series combines the strength, ground clearance, and durability of dynatrac's prorock axle assemblies with the safety systems and mounting bracketry necessary for a bolt-on installation into the new Jeep Wrangler JK. Additional performance enhancements include billet steel housing ends, choice of ring-and-pinion ratios, and large tapered roller axle bearings.

For more information, contact:dynatrac, (714) 596-4461,

Amsoil Severe Gear Synthetic Extreme Pressure Lubricant
Amsoil's 75W-110 severe-duty, synthetic gear lubricant is heat-resistant and has increased viscosity for towing, hauling, steep-hill driving, and off-road applications where high temperatures and frequent stop-andgo driving conditions are prevalent. Best of all, the intervals between maintenance of the gears is extended as well thanks to its synthetic properties.

For more information, contact:Amsoil, (800) 725-4645,

TJM Pro Locker
The TJm pro locker differential has been made for all 60- to 80-series Toyota land Cruisers. each locker contains an air-operated piston-style actuator that eliminates oil buildup inside the air lines. in addition to the locker's actuation, the internal components of the unit are larger than stock, thereby allowing for increased durability and a stronger hosing.

Additional features of the locker are its reinforced external rubber air lines, pretensioned 10mm hemisphere bolts for optimum strength, heavy-duty mounting hardware, and an industry-first recessed led switch that shows when the locker is engaged and disengaged. A heavy-duty wiring harness is also included with the unit.

For more information, contact:TJm, (865) 670-1556,

Currie Enterprises Fabricated Differential Housing
Currie enterprises C-mac fabricated differential housing is built for extreme use. The housing is available in either 4130 chrome-moly or mild steel. The ideal housing for extreme rockcrawling, the laser-cut 3/16- inch-thick material is bent to shape, not welded out of pieces.

For more information, contact:Currie enterprises, (714) 528-6957,

Powertrax Lock-Right Locker
The no-slip traction of the powertrax lock-right locker comes from a fully automatic locking rear unit. As the vehicle travels straight, both axles are locked together; when entering and exiting corners, the internal differentiation of the internal gearing is released. The locker is currently available in a number of applications for some of today's more popular trail vehicles, including Jeep Wranglers, Toyota land Cruisers, and Ford Broncos.

For more information, contact:powertrax, (864) 843-9231,

Superior Axle Jeep JK dana 44 rear Chromemoly Shafts
Superior's all-new Jeep JK Wrangler dana 44 rear chrome-moly axleshafts have been fabricated to meet one goal: Absorb the shock load rather than break under it. A closer inspection of the shafts reveal that they're made from SAe4340 that has been induction-hardened, CNC-turned, and rotoflow spline-rolled for toughness. For additional performance on and off the road, the shafts' profiles have been adjusted.

For more information, contact:Superior Axle & Gear,(888) 522-2953,

ARB Air Locker Locking Differential
ARB Air lockers are synonymous with the whole notion of Jeeping. easily known throughout the off-road world as being one of the finest airactivated locking differentials on the market, these differentials provide the ultimate in traction by injecting compressed air into the differential, which then locks the gears in place.

Installed on your daily driver, the system goes unnoticed. however, at the push of a button, the system can be engaged and then disengaged. Kits are available for virtually any Jeep, land Cruiser, or other trail rig you can imagine.

For more information, contact:ARB 4x4 Accessories,866) 293-9078,

Full Spider Rock Guard Differential Cover
The name should tell you a little something about this item. Designed for some of today's more popular trail rigs, the Full Spider rock Guard rear differential cover is fabricated from .500-inch-thick CNC plasma-cut flange with attached .625-inch-round cold-rolled steel legs. The Full Spider will protect your ring-and-pinion set from any rocks or stumps you may encounter.

Installation is a snap since each Full Spider cover contains CNC-machined, counter-bored bolt holes. The phosphate-primed and powdercoated durable black hammer-tone finish is able to withstand whatever is put in its path without chipping or cracking and is still able to look good for the ride home.

For more information, contact:purple Cranium products,(313) 581-0032,

West Coast differentials installation Kits
When replacing either a front or rear differential, it is important to have a high-quality kit consisting of the appropriate seals, shims, and bearings.

West Coast differential offers kits specifically for this purpose for many popular makes and models of trucks. included in each installation kit are American-made Timken bearings, pinion seals, pinion shims, a pinion nut, crush sleeve, gear-marking compound and brush, loctite compound, silicone gaskets, and instructions. All components are manufactured from the highest-quality components.

For more information, contact:West Coast differentials,(800) 510-0950,

Detroit Locker Nospin Differential
Detroit locker's NoSpin differential is considered to be one of the most rugged positive-locking units available for axles ranging from 3,000- to 70,000-pound capacities. The fully automatic positive-locking traction differential maximizes traction by delivering 100 percent of the torque and power to both drive wheels.

A speed-sensitive automatic locking mechanism senses the various terrain and any slippage and compensates by locking the differential in place.

For more information, contact:eaton, (800) 328-3850,

Dana Spicer Trac-lok differential
Dana Spicer Trac-lok differential utilizes the traction of both wheels to create increased traction control in adverse driving conditions. By employing a clutch plate and disc arrangement, the Trac-lok is able to continually transfer as much torque as possible without compromising the handling characteristics of the vehicle. The system is available for all Jeep models, including the liberty, Wrangler, and Grand Cherokee.

For more information, contact:dana Corporation,


Superior, WI 54880
Currie Enterprises
Corona, CA 92880
Huntington Beach, CA 92647
Superior Axle & Gear
Rancho Cucamonga, CA 91730
Cleveland, OH 44114
Chicago, IL 60609
Precision Gear
Suwanee, GA 30024
Advance Adapters
Paso Robles, CA 93446
Eaton Corporation
West Coast Differentials
Rancho Cordova, CA 95742
Reider Racing
Stak 4x4
El Paso, TX 79936
Dana Corporation
Fort Wayne, IN 46801
Tom Wood's Custom Drive Shafts
Randy's Ring & Pinion
Everett, WA 98204
J.E. Reel Drive Line Specialists
ARB 4x4 Accessories
Solid Axle Industries

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