Went back over this thread and looks like BlueOvalFitter always has been using Motorcraft FL-400 oil filters. He just changed the oil from conventional MS5K 5W20 to Castrol SynBlend 5W20.
One variable was changed - just the oil. If the new better flowing oil fixed the start-up rattle with the same filter, then he's found the root cause of the rattle.
Originally Posted By: BlueOvalFitter
dnewton3, I use MC FL-400s filters. My truck has 93K miles on it. Which oil would you use in it; conventional 5W20, semi-syn 5W20-5W30, synthetic 0W20, 0W30, 5W20, or 5W30?
Originally Posted By: BlueOvalFitter
Originally Posted By: Jim Allen
Thanks for the update.
To be clear, you changed oil but not filter?
And you went to a 5W20 but what was the original oil viscosity?
I originally had MS5K 5W20 in it. I drained that and installed Castrol SynBlend 5W20 and a new MC FL-400s filter.
The MS5K was the first time ever my engine had conventional oil used in it, since I had bought it new. (6 miles when new) Currently 93K miles
One variable was changed - just the oil. If the new better flowing oil fixed the start-up rattle with the same filter, then he's found the root cause of the rattle.
Originally Posted By: BlueOvalFitter
dnewton3, I use MC FL-400s filters. My truck has 93K miles on it. Which oil would you use in it; conventional 5W20, semi-syn 5W20-5W30, synthetic 0W20, 0W30, 5W20, or 5W30?
Originally Posted By: BlueOvalFitter
Originally Posted By: Jim Allen
Thanks for the update.
To be clear, you changed oil but not filter?
And you went to a 5W20 but what was the original oil viscosity?
I originally had MS5K 5W20 in it. I drained that and installed Castrol SynBlend 5W20 and a new MC FL-400s filter.
The MS5K was the first time ever my engine had conventional oil used in it, since I had bought it new. (6 miles when new) Currently 93K miles