4×4 Repair and Service

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Vehicles with four-wheel drive provide extra traction for wet, icy, or rough roads, all of which occur in in St Louis climate during the year. It simply means that the engine delivers power to all four wheels equally instead of only two. With a specialized vehicle comes much-needed special care and attention. Call Sant Automotive at 314-849-2900 if your 4×4 is not functioning or if your 4WD doesn’t engage. 

All About 4×4 Car Repair

Some common issues with 4-wheel drive systems that may require repair include problems with the transfer case, driveshaft, HUB/lock actuator, and the gear system.

Parts that can affect 4WD performance and function:

  • Transfer Case: If the transfer case is not functioning correctly, it cannot effectively engage the 4×4 system, leading to its failure. A malfunctioning transfer case is typically caused by wear and tear, damaged gears, and lack of fluid.
  • The Front Axel Actuator: Another possible reason for a non-working 4×4 is a problem with the front axle engaged. The 4×4 system requires the engagement of both the front and rear axles. If the front axle does not engage properly, the system cannot function. Typically, potential failures can include vacuum leaks or electrical issues that prevent the actuator from engaging the front axle appropriately.
  • Faulty Switches: Faulty 4×4 switches can also lead to the failure of the 4×4 system. Over time, these switches can corrode and wear out, affecting their ability to engage the 4×4 system. Often, a sure sign of a switch problem is when the indicator light fails to illuminate or if it blindly flashes.
  • Drive Train: Drive chain slippage in the transfer case may also impede 4×4 functionality. If the chain within the transfer case becomes loose or worn, it can slip off the gears. When this happens, it cannot propel the movement that the 4×4 system needs to work optimally.
  • 4×4 Fuse or Relay: An issue with the 4×4 fuse or relay can also prevent the system from working. If the relay or fuse is blown due to an electrical surge or failure, the 4×4 system won’t engage. It’s always essential to check the fuses and relays if your 4×4 is not working.
  • Front Differential: Lastly, problems with the front differential can cause 4×4 issues. The differential is what allows the wheels on the same axle to rotate at different speeds. If the front differential is damaged, it can interfere with the effective operation of the 4×4 system.
(source: “Common Problems With Your 4×4 and Solutions” on motorbiscuit.com) (source: “What Causes a Four-Wheel Drive System to Not Work?” on yourmechanic.com)  

Frequently Asked 4WD Repair Questions

Your 4WD light could be on due to several reasons. Primarily, it means there’s an issue with the four-wheel drive system. Here are some common causes:

  • Faulty sensors: The transfer case control module monitors the system with multiple sensors. Faulty sensors may cause the 4WD light to turn on.
  • Defective solenoids: The transfer case motor moves the transfer case gears with solenoids that can become defective over time.
  • Transfer case issues: Problems with the transfer case itself, such as low oil, worn-out components, or internal damage can result in the 4WD light being on.
  • Wiring faults: Any damage or problem in the wiring, corrosion, or poor connections can trigger the 4WD system light.
  • Control switch failure: The 4WD switch communicates driver input to the module, and a failure can illuminate the light.

To diagnose and repair the problem, it’s best to refer to a professionally trained automotive technician. They can perform an inspection and fix the issue accordingly.

The cost of fixing a 4WD (four-wheel drive) system can vary significantly based on the exact issue and vehicle model, ranging from a few hundred to several thousand dollars. The expense is primarily impacted by the type of the repair necessary. For instance, if the problems involve simple fixes such as transferring case fluid changes, then the costs can be around a few hundred dollars. However, if the repair process involves complex issues like replacing the transfer case, these costs can escalate to a few thousand dollars.

Technically, yes, you can still drive with a bad 4-wheel drive actuator, however, it is not recommended. A faulty 4-wheel drive actuator can lead to problems with the vehicle’s drivability, including traction issues, particularly in off-road conditions or poor weather. Additionally, it could potentially cause damage to the drivetrain. It’s in your best interest to have a faulty 4-wheel drive actuator repaired or replaced as promptly as possible to prevent further complications.

Symptoms of a bad transfer case include abnormal noise such as grinding or clattering, difficulty shifting gears, vehicle jumping in and out of four wheel drive, leaking of transmission fluid, shaking when accelerating, and the vehicle not moving despite being in gear. In some severe cases, the transfer case may fail completely, leaving the vehicle incapable of movement.