Gear Drive VS Chain Drive Transfer Cases

Transfer cases come in two types - gear driven and chain driven. Gear drive transfer cases have become somewhat of an artifact of the past, as majority (if not all) of today's four wheel drive vehicles utilize a chain driven gearbox. Gear drive transfer cases have an obvious advantage in terms of strength, but are heavy and not always user friendly. An important characteristic in the transition from gear to chain drives is smooth engagement, even "on-the-fly". In the absence of a complex network of synchronizers, gear drive transfer cases usually require the vehicle to come to a stop (or close to it) in order for the gears to mesh properly. Additionally, as the complexity of transfer cases and drivetrain systems increases, chain drive units have presented themselves as a more economical option. However, there's no denying that, for hardcore wheeling, a gear driven transfer case is the obvious choice.

Gear Driven Transfer Cases

Gear driven transfer cases are well known for their strength, durability, and versatility. Many popular models can shift between hi-range, low-range, and 2wd, 4wd independently. Those that don't carry this feature can usually be converted to do so, a modification known as twin sticking. A gear driven transfer case does not have many things that can go wrong, though they don't always engage as smoothly as chain driven cases. Most are large, cast iron cases with a relatively high weight, but can also take a serious beating on the trail. Their simple design makes them easier to repair, rebuild, and/or modify for the average DIYer with basic mechanical skills. Popular gear driven transfer cases include the NP205, Dana 300, and Dana 20.




Inherently stronger, simple design

Noisier, particularly in low range

Rugged, dependable, less to go wrong

Difficult shifting, not synchronized, inherently difficult to mesh gears when engaging low range

Relatively simple to upgrade, plenty of aftermarket options for popular gear drive cases

Relatively high weight


Chain Driven Transfer Cases

Chain driven transfer cases are more common today, as they're lighter and, in some ways, more user friendly. They're typically easier to shift on-the-fly, which is useful when a driver wishes to engage four wheel drive while maintaining momentum. Weight is another benefit, as modern transfer cases are often cast from light weight materials such as aluminum and magnesium. A common misconception is that a chain drive case is weaker because it has a puny chain transmitting power to the drive shaft, when in fact that chains are quite large (several inches across). However, the chains can stretch over time and if severe enough the chain can be pitched off their gears. Chain drive cases are also more sensitive to lubrication, or lack thereof, so it is critical to monitor the fluid level and change it anytime the transfer case is submerged. Popular chain driven transfer cases include the NP203, BW1356, and BW1345.




Shift-on-the fly (high range). Electric shifting common on many chain driven transfer cases.

Not as strong as gear driven - for all intents and purposes, chain driven cases display adequate strength, but are not typically as robust as a comparable gear driven unit

Light weight

More complex system

Quiet operation, smooth shifting

Electric shift mechanisms can fail, mechanical shift mechanisms less likely to experience shifting problems