Owning a truck or SUV with a four-wheel drive can be great when you need additional traction when driving through snow, mud, or rough terrain. If the four-wheel drive stops working, you may need to find a shop that handles 4x4 transfer case repair and have them determine why the transfer case is not operating correctly.
Many modern four-wheel-drive trucks use a transfer case shifted with a switch on the dashboard instead of a manual lever. These transfer cases use a small servo inside the case to shift from two-wheel drive into four-wheel drive.
The electronic cases are very convenient, but if the servo stops working, the case will not shift. A 4x4 transfer case repair shop may need to pull the transfer case out of the vehicle and disassemble it to repair it. While these systems are durable and are not any more prone to failure than a manual case, the system depends on power, a switch, the servo, and fuses or breakers in the system.
This makes it a little more challenging to determine the cause of the failure, but sometimes the repair is as simple as changing a fuse in the system. Many of these electronic transfer cases also report errors to the ECM, so a scan for fault codes may tell the tech where the problem is located in some trucks.
Manual Transfer Cases
Older trucks and SUVs with manual shift transfer cases can experience issues with the case shifting correctly as well. When the transfer case does not go into gear, the truck will only get power to the rear wheels.
Most manual transfer cases use a series of gears inside the case. They move into different positions to engage other gears when you pull the shift lever from two-wheel drive to four-wheel drive. If the fork that moves the gearset is bent, the gears may not engage, but a 4x4 transfer case repair shop will need to take the transfer case apart to determine if that is the problem.
Wear And Damage
No matter how your transfer case shifts, the gears can be damaged inside, causing misalignment issues that make it difficult for them to engage fully. The bearings can also wear, especially on a vehicle with high mileage. As things wear down inside the transfer case, shifting becomes more and more difficult.
A 4x4 transfer case repair shop may be able to repair the case, but sometimes the cost of a remanufactured case that is ready to be installed is less expensive than making the repairs to the old one. The repair shop can go over the options with you and help you decide what is the best course of action for you.