The D-300 transfercases were built by Dana Spicer with 2.62:1 gears. Many years the 4:1 were created for much lower range. It must still be noted that with tall gears and massive tires simply getting a lower transfercase will create a new strain or failure point. That being said, these are great crawling gears. There have been at least a couple companies to make 4:1 gears, ourselves being one of them. We take our work and duty to provide quality parts very seriously and love these gears.
This particular build by us is the cream of the crop for Spicer Model 300 transfercases. This transfercase is fully remanufactured will nearly everything brand new. The gears are new 4:1 low range with 1:1 high range. The rear output shaft, housing, and bearings are the large HD Rear output supplied by Advance Adapters. The intermediate shaft is a USA Made, guaranteed to rockwell at or above 62. The bearings are all US or Japanese. Please inquire direct for pricing depending on build. We do keep these ready to build.
Spicer model 300 transfer-cases have a passenger-side front output and a centered rear output, unlike like previous Dana models, They do not have an output gear mounted to the transmission main shaft but a gear that rides on its own, bearing mounted input shaft. The rear output and intermediate gear shafts are the only real “weak points” and can be upgraded. Although they are still much stronger than their predecessors. The Scout version of the D-300 that was only built in 1980 has the same Texas pattern face and transmission mounted output gear as did the D-18/20 and can be very confusing, as it looks rather like a D-20. We have even found what appears to be in-between models with parts that do not belong with the rest and housings drilled differently leaving parts of the casting left entirely un-drilled from the factory.