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If you’ve made your way to this article, odds are you are pretty familiar with the Ford Bronco, or at least you are familiar with what a transfer case is in a vehicle.
For those who might just be curious overall, let’s take a moment to define a transfer case.
In a vehicle, a transfer case is an important component of the drivetrain. This is a component of all-wheel-drive vehicles and four-wheel-drive vehicles. Essentially, the transfer case helps to distribute power between the front and rear wheels. It does this by working with the transmission and the driveshafts.
There are different types of transfer cases depending on the vehicle, and that is the situation with the Ford Bronco as well. There are a few main types of transfer cases that can be installed in the Ford Bronco model:
Dana 20
Borg-Warner BW1356
We’re going to go into a few details regarding these two different transfer case options, pros, and cons, etc. Especially if you have an older model, this can be extremely helpful when you’re looking for parts for service, repair, or a rebuild. The first Ford Bronco was introduced in 1965 (1966 model), and it paved the way for the sport-utility realm, so you’ve got an impressive 50+ year history on this vehicle (and all its parts).
Dana 20
The Dana 20 transfer case was manufactured from the mid-1960s through the 1970s. This is the type of transfer case the first Ford Bronco 1966 Model was designed and manufactured to use. This transfer case is also seen in many Jeep models and two-door SUV and two-door truck models, including the International Harvester Scout off-road vehicle.
This transfer case is a medium-duty, gear-drive reliable unit that is durable and made of cast iron. Cast iron makes this component fairly indestructible, so it’s no wonder that material was chosen for a rough and tough off-road vehicle design. The Dana 20 is a part-time and manual-shift style transfer case, and it offers dual modes and dual ranges.
On Jeep and Bronco forums, a common issue with the Dana 20 transfer case is its 2.03:1 low range ratio. Today though, TeraFlex offers a 3.15:1 low range ratio option for the Dana 20.
Another issue you’ll see owners discussing is the transfer case slipping out of the two-wheel drive. Mechanics and home tinkerers have found solutions by addressing the input and output shafts and ensuring all the internal gears are operating correctly and smoothly. With older transmission cases, checking for broken gear teeth is highly suggested. In some cases, a full rebuild or remanufacture is necessary to resolve these issues.
There are also shift pattern diagrams for the rear axle vs. the front axle to help drivers operate in 2WD rear low, 2WD rear high, 2WD front high, 4WD low, 4WD high, and neutral front and rear correctly.
Borg-Warner
The Borg-Warner Corporation was founded in 1928 and through the 1950s the company focused on manual and automatic transmissions. The first Borg-Warner full-time, four-wheel-drive transfer case was introduced in 1973, and there are over ten different transfer cases by this brand in circulation still:
Model BW1356
Model BW4444
Model BW4445
Model BW4446
Model BW4447
Model BW4481
Model BW4482
Model BW4484
Model BW4485
Model BW4493
Model BW4494
In terms of the Ford Bronco, between the late 1980s and mid-1990s, many of the 4×4 and full-size Bronco models had the BW1356 transfer case installed. This transfer case is made from magnesium and comes in manual and electronic shift varieties. It offers high range direct drive gears and low range with a ratio of 2.69:1.
Some of the most common issues with the almost 30 or 40-year-old BW1356 transfer cases are grinding noises with a shift to 4WD, clunkiness, or slipping and popping out of low gears in motion. This particular transfer case also sometimes puts excess pressure on the engagement sleeve which amplifies wear and tears on components like the fork. Oil pump issues are also known to arise, creating lubrication issues for the system.
Popular and Available
There are a lot of opinions when it comes to transfer cases and for off-road vehicles needing 4WD, you definitely do not want a transfer case issue. The Dana 20 and BW1356 are extremely popular transfer cases with the Ford Bronco models, and the good news is that replacement parts, and even entire replacement transfer cases, are readily available and affordable.
The post Ford Bronco Transfer Case Specs, Identification, and Common Problems appeared first on The Mechanic Doctor.
