Transfer Case Decisions - Gear Drive vs. Chain Drive

    Which One Is Right For You?

    Harry WagnerPhotographer, Writer

    In the early days of 4x4s, transfer cases like the Spicer 18, Dana 300, and NP205 were the norm. These cases all feature iron cases and are gear-driven for incredibly strength, but as manufacturers searched for ways to make 4x4s quieter and more fuel efficient the NP231, NP241, and NP271 emerged. By contrast, these transfer cases use aluminum cases and are chain-driven with planetary gears of varying size (depending on the application).

    These two transfer cases have been the cornerstone of ¾- and 1-ton truck applications for decades

    We went to National Fleet Solutions where an NP205 and an NP271 transfer case spilled their guts for us at the hand of shop manager Aaron Lechner. These two transfer cases have been the cornerstone of 3⁄4- and 1-ton truck applications for decades, and both designs have their advantages and disadvantages depending on your budget, space requirements, and how you primarily use your 4x4. Read on to help determine which one is right for you.

    NP271 or NP273, What’s the Diff?
    The NP271 that we used for this story uses a manual, floor-mounted shift lever, while the NP273 is essentially the same transfer case with an electric shift motor. The NP273 also adds a synchro ring for shift-on-the-fly capabilities. Otherwise the cases and internals for both transfer cases are identical, and components can easily be swapped between the two cases.

    When viewed next to each other, it is easy to see how much larger the aluminum, chain-driven NP271 case (top) is compared to the cast iron, gear-driven NP205 transfer case.