Im thinking about going to Amsoil Signature 5w20.

What about you guys ?

 

Lots of miles on 2 engines, never a problem with Motorcraft 5-20. It's my opinion that those premium oils are a waste.

 

No point in using the Amsoil unless you are going for extended oil change intervals and will be using an Amsoil or other premium filter designed for synthetics and extended change intervals. If you change every 5k, just use Motorcraft oil and filters.

 

Motorcraft semi synthetic 5w20 and Motorcraft 820S oil filters here. Change every 3-4000 mi, no issues. '05 5.4 with 77k on it.

 

Well no v8 here but I use mobil1 extended performance oil and filter. It's 15k miles or 1 year. I've been using it since my truck had 9k miles changing it every 10k or so. Walmart dot com has a 5 qt jug for $28 and you have to get the filter from auto zone for like $18. So $46 oil change but lasts the amount of 3 normal changes at 3k. That's $15 per change pretty much.

 

Motorcraft semi-synthetic and Motorcraft filter changing every 5k miles because it's easy to keep up with.