2002 f150 4.6 270,000 miles
Just had the motor replaced. I've cleaned the MAF in the past, so it's never been replaced. My mechanic (Ford certified) informed me to buy a new one, even after he cleaned it, that it was still running a little lean. When I checked the prices it was $520 plus tax from the dealership. I'm not trusting AutoZone or Oreilly's on it either. Any good aftermarket's?

thanks

 

https://www.rockauto.com/en/catalog/...ow+sensor,5128

The ones with the hearts are the most popular.

 

Question; what trouble is it believed to be causing?
If none, why replace it just on his recommendation. He might be wrong without telling you what the readings are.
Such as the long term fuel trim table readings etc.
These tables have a plus or minus range of 25% and to be near perfect should run near plus or minus 5%.
Most aged vehicles won't run this close for a number of reasons.
The mass meter in only one part of the reasons for any shift.
Do what you want but not expect and worthwhile difference in performance "if" it is ok now.
Good luck.