51-5911 : Heavy Duty Toyota Truck gear driven transfer case gear reduction housing. (#51-5911)

51-5911 : Heavy Duty Toyota Truck gear driven transfer case gear reduction housing.

On the 4.7 gears, the stock case must be machined or ground to provide clearance for the cluster gear. You can grind the necessary clearance; however, it is recommended to machine the case for this clearance.

If your not sure about this grinding or the machining process, we now offer a new heavy duty front Toyota housing. Our new Toyota HD housing can be used as a crawler box with stock Toyota gears or with our Sumo low gear sets. It can also be used as a new front housing for the lower gear sets listed above. This housing will save you time and money. When installing our Sumo low gears into a stock Toyota housing, grinding & machining on the stock case is required. Our housing has been engineered with additional clearance for our Sumo gear sets. Thus, hours of grinding & expensive machining labor are eliminated. This housing is made from 356-T6 heat-treated aluminum alloy with an average thickness of .550”. A “stock” housing is die cast aluminum and only has an average wall thickness of .200”.

Top Review


by Jonathan, from Los Alamos, NM

Great part for the ultimate gear drive transfercase

My junkyard case had a crack between the crossmember mount and the bearing support. This a high stress reagion on the case an grinding a stck case down to fit 4.7 gears adds to the potential of the case cracking. The AA case is pre-clearanced and is twice as thick as the stock case making my new transfer case much stronger for the increased stresses of the low range gears.

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