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2. Toyota L/C Orion Transfer Case

Orion 4-to-1 Transfer Cases: For years Toyota Land Cruiser enthusiasts have dreamed of finding a durable, low-geared transfer case able to withstand rugged conditions. With the introduction of the Advance Adapters Orion case, their dreams just became a reality. The Orion offers the strength of cast iron coupled with the rock crawling capability of a 4:1 gear set. 

Besides the cast iron case and lower gear set, the Orion has other additional benefits over a stock transfer case. Benefits include a larger 34mm idler gear shaft, wider needle roller bearings for improved load distribution, and a fully gusseted idler shaft area on the case. This revolutionary transfer case will eliminate any downtime due to case failures. There is no need to modify either driveshafts for the installation since the length and dimensions of Orion STD-duty are nearly identical to the stock case.

The Orion replaces stock transfer cases in Toyota Land Cruisers built between 1963 and July of 1980. Stock transfer cases built during this 18 year span are either a 10-spline case coupled with a 3-speed tranny or a 16-spline case coupled with a 4-speed tranny. Prior adaptations of other transmissions using Advance Adapters conversion products will also be compatible with either Orion series transfer case.

This case replacement has the same external width, eliminating driveline modifications. The casting contours that outline the low speed output gear will position the drain plug approximately .500 lower on average. The new low ratio gear set supplied replaces existing gear sets except for the PTO gear or PTO spacer sleeve.

Orion Low Range Transfer Case: The Orion kits come with a new cast iron case, four new gears, a new 34mm cluster pin, and a complete gasket bearing and seal kit. This transfer case, however, is not a complete ready-to-bolt-in unit like the Atlas. The transfer case does require the use of your stock front and rear output shafts and housing. The new unit also requires the use of the stock P.T.O. gear and inspection covers. Orion4

The Orion transfer case requires the complete removal and disassembly of your stock Toyota transfer case. Once the stock transfer case is removed from the vehicle it becomes a donor for the new Orion case. This kit requires that you reuse your stock fasteners, front & rear housings, retainers, shafts, shift fork, clutch sleeves, and cover plates from your original transfer case. You are supplied a full rebuild kit to replace all bearings, races, O-rings, seals, and gaskets. Shims for the rear output shaft retainer are also supplied to set the bearing pre-load. Do not discard shims, washers, sleeves, and spacers from your stock yokes and shafts. Although the instruction sheet provided with your new transfer case will initiate the steps to install the Orion, it is advised that you also obtain a shop or repair manual that covers your specific application. 

Transfer Case Shafts - We do carry stock replacement output shafts for the Orion transfer case. We have found that most stock transfer case output shafts have excess wear on the gear journals. These new shafts will provide a closer tolerance installation for the Orion gears. O40500 - T/Cs up to April 1975 O40501 - T/Cs April 1975 to July 1980

Orion Transfer Case Points of Concern: The success of an Orion Transfer case installation is dependant on the condition of the necessary components that are to be reused from your stock case. Some of the most critical components that require your attention to detail are as follows:

HI/LOW CLUTCH SLEEVE - Inspect for excessive or worn splines. The splines should not be tapered throughout the sleeve width. You will notice the looking tapers or only at the last .070 to the contact sides of the sleeve towards each gear. If you need a new sleeve, O50010

SHIFT FORK LOCK BALL AND COMPRESSION SPRING - We have provided a new ball, spring, and brass set screw to be used for your installation. The ball provided measures 10mm and will tighten up the tolerance in the shift fork bore. We have also provided a new spring which has a greater holding capacity than an older worn out spring. The new brass set screw will take the guess work out of setting the tension on the spring and ball inside the new shift fork. The brass set screw should be installed with a bit of Loctite to retain it, and the hex should be seated completely to the shift fork. O60050 - 10mm Ball P/N O60051 - Shift Fork Spring, O60052 - Set Screw P/N O60040 - New Shift Rail O60041 - O-RINGS

THRUST WASHERS & OUTPUT SHAFTS- The thrust washers are an important and critical area when installing the Orion gears on your Toyota shaft. The first step is to inspect the transfer case output shaft for excessive wear and to make sure the gears fits the shaft. If your shaft is worn excessively, the gear will be a loose fit or will be able to wobble. If this is the case with your shaft, replace it. We do offer replacement shafts. If the shaft is in good shape, then proceed. The end play of the gear on the shaft must be checked. The new Orion gears are the same width as a stock gear set. Gear end play should be at .008"-.012".