Have a 2011 F150 lariat crew with 3.5 eco boost. I am experiencing 1st gear shifting problems. when cold going from reverse to forward 1st gear seems to slip and when I try to accelerate tit then slams into first. it is a very violent shift and almost spins the tires. once the trans is warm it does not seem to do it anymore. other owners I have talked to say there is incorrect grease in the shifting mechanism which coiuld take out 1st gear clutch. anyone else had this problem and what would be the fix.