Difficulty changing gears – Low or dirty transfer case fluid can affect your transmission’s ability to shift gears. It can also result in your car unexpectedly falling out of four-wheel drive. Loud noises while driving – As the transfer case fluid loses its lubricating properties, friction will occur inside.Click to see full answer. In this regard, what happens when a transfer case goes bad?If the seals leak, fluid escapes and is no longer able to properly lubricate the interior components of the transfer case. Eventually the parts inside will wear out and overheat. If this happens, the transfer case will be rendered useless and the four-wheel drive operation will not work.Beside above, when should I change transfer case fluid? If the fluid runs low or becomes contaminated, it can lead to failure of the differential. To avoid this issue, it is recommended that the transfer case fluid be changed periodically, normally every 30,000 miles, especially in vehicles that tow or use four-wheel drive often. Similarly, you may ask, how do you know if you have a bad transfer case? Strange noises: You may hear one or more odd sounds coming from the transfer case, or from under your vehicle. Shifting gears becomes difficult: This can happen with both manual and automatic transmissions that work with transfer cases. Do you need a transfer case to drive?A transfer case is a specialized component that is used on four-wheel drive and all-wheel drive vehicles. It is essential on vehicles that use both front and rear axles to drive. And in the case of 4x4s, each of the four wheels need to be powered.