Steam Assisted Gravity Drainage (SAGD) is a common thermal recovery technology that uses steam to heat and extract oil from bitumen reservoirs. It consists of an upper horizontal injector and a lower horizontal producer. Varied lateral extent, thickness, and frequency of shale layers can be observed and these shale layers can substantially impair the pay zone's vertical permeability and slow down the SAGD process by interfering with the flow of steam and oil. Henceforth, identifying shale problems and finding solutions to them has become critical in SAGD production. This study investigated shale issues in the SAGD process from the simulation perspective. Hypothetical shale cases were built in SAGD simulation models using the CMG STARS simulator. In addition, the vertical well pair spacing in the SAGD simulation model was changed to test it as a remediation technology to reduce the negative shale impact on the steam chamber, and the SAGD performance.