Front end shakes when I get to about 40 mph feels like a flat tire but the tires are fine and the lugs are tight. I have removed the drivers side front tire and visually inspected but everything seems to be tight. What checks can I do to diagnose this problem?
Jack up front of vehicle and manualy shake the wheel to see if it has any side play or top/bottom movement.
Check the rim for damage/bent.
Any abnormal tire wear? Try rotating the tires to see if it makes any difference.