2003 GMC Yukon

Engine Performance problem
2003 GMC Yukon V8 All Wheel Drive Automatic 68000 miles

I have a 03 Yukon Denali XL and just had my spark plug changed. Everything seems to be running good but I am just wondering. Do you set the gap of the spark plugs to your car specifics or the gap that is set on the new plugs. How Would I know if the plugs were installed correctly and what is the gap size on a 03 XL DENALI?
May 23, 2008.

Hi there.

The plug gap should be.060" or 1.52mm. This should be checked with a wire type gauge. All plugs are pre gapped, but a good mechanic will re check when installing. The only way to check them is to pull a plug and re check gap.

Mark (mhpautos)

May 24, 2008.