Transfer case troubleshooting (Chevrolet Captiva 1 2006-2018: Transmission: Transfer case)

Visual inspection / physical control

Inspect easily accessible and visible parts of the system for obvious signs of damage or conditions that could lead to a malfunction.
Check for correct lubricant levels and viscosity.
Determine the exact operating conditions under which the complaint occurs. Pay attention to factors such as vehicle speed, road conditions, ambient temperature and other features.
Compare driving characteristics or sounds, if any, with a known serviceable vehicle and ensure that there is no attempt to correct the normal condition.

Intermittent Symptom

Test the vehicle under the same conditions reported by the customer to ensure that the system is working properly.

Increased noise while driving

Cause	Remedy
Verify that the transmission fluid and transmission oil levels are correct before performing system diagnostics. See "Transfer case fluid change".
Water or contamination in the lubricant Water or contaminants in the lubricant that cause excessive torque converter slip ratio can cause rubbing, snarling, or groaning sounds in the rear differential under light or constant load conditions.	Change the lubricant and flush the transfer case from contaminated fluid.
Weak propeller shaft mounting bolts	Tighten screws if necessary.
Wear of the hinges of equal angular speeds of the cardan shaft	Replace driveshaft assembly.
Wear of the hinges of equal angular velocities of the axle shaft of the wheel drive	If necessary, replace the constant velocity joints.
Incorrect transmission oil in the transfer case	Change transmission oil.
Bearing noise in transfer case Noise such as rubbing or hum increases or decreases depending on vehicle speed.	Check if the fluid level is correct. Top up if necessary. If necessary, if noise persists, repair or replace internal components.
Howling noise of the gearbox in the transfer case The howling noise increases or decreases depending on the speed of the vehicle.	Check if the fluid level is correct. Top up if necessary. If necessary, if noise persists, repair or replace internal components. The following factors may contribute: Incorrect clearance between the gears of the reducer Worn or damaged gear teeth Increased noise in the gearbox with final drive assembly Increased noise in the rear differential

Increased noise when coasting

Cause	Remedy
Verify that the transmission fluid and transmission oil levels are correct before performing system diagnostics. See "Transfer case fluid change".
Weak propeller shaft mounting bolts	Tighten screws if necessary.
Wear of the hinges of equal angular speeds of the cardan shaft	Replace driveshaft assembly.
Wear of the hinges of equal angular velocities of the axle shaft of the wheel drive	If necessary, replace the constant velocity joints.
Incorrect transmission oil in the transfer case	Change transmission oil.
Bearing noise in transfer box Noise such as rubbing or hum increases or decreases depending on vehicle speed.	Check if the fluid level is correct. Top up if necessary. If necessary, if noise persists, repair or replace internal components.
Howling noise of the gearbox in the transfer case The howling noise increases or decreases depending on the speed of the vehicle.	Check if the fluid level is correct. Top up if necessary. If necessary, if noise persists, repair or replace internal components. The following factors may contribute: Incorrect clearance between the gears of the reducer Worn or damaged gear teeth Increased noise in the gearbox with final drive assembly Increased noise in the rear differential

Unstable noise

Cause	Remedy
Verify that the transmission fluid and transmission oil levels are correct before performing system diagnostics. See "Transfer case fluid change".
Weak propeller shaft mounting bolts	Tighten screws if necessary.
Wrong gear oil	Change transmission oil.

Constant noise

Cause	Remedy
Verify that the transmission fluid and transmission oil levels are correct before performing system diagnostics. See "Transfer case fluid change".
Low gear oil levels	Faulty seals or other types of leaks can contribute to below normal fluid levels. See "Transfer case leak diagnostics". Top up gear oil to the correct level.
Wear of the hinges of equal angular speeds of the cardan shaft	Replace driveshaft assembly.
Bearing noise in transfer box Noise such as rubbing or hum increases or decreases depending on vehicle speed.	Check if the fluid level is correct. Top up if necessary. If necessary, if noise persists, repair or replace internal components.
Howling noise of the gearbox in the transfer case The howling noise increases or decreases depending on the speed of the vehicle.	Check if the fluid level is correct. Top up if necessary. If necessary, if noise persists, repair or replace internal components. The following factors may contribute: Incorrect clearance between the gears of the reducer Worn or damaged gear teeth Increased noise in the gearbox with final drive assembly Increased noise in the rear differential

Transfer case leak diagnostics

Cause	Remedy
Worn, scored or missing drain and/or filler plug	Install new plugs and tighten to specification.
Worn or damaged input or output shaft seal	If necessary, replace the output shaft seal.
Cut or damaged mainshaft case O-ring	Replace O-ring if necessary.
Wear of internal shaft seals Worn or damaged internal shaft seals can be detected by fluid leakage around the vent hole at the bottom of the cover.	Replace seals if necessary.
Cut or damage to the O-rings at the junction of the gearbox with final drive assembly and transfer case	Replace O-rings if necessary.
Porosity or leakage of sealing surfaces of boxes or crankcases	Replace the transfer case assembly if it cannot be repaired.