Hi, I am a new member that has been reading the boards for quite some time. I have a 2001 King ranch with 70,000 miles on it. I have been using non synthetic oil (5w20) and would like to know what weight synthetic this matched up to. Any help is appreciated. Thanks.

 

you should continue to use the 5w20 until your engine gets alot of wear then i'd suggest going a little thicker.these new engines are built with much smaller tollerances than older engines and that's why you have to use 5w20 which is thinner.once you get alot of miles you'll probably need to switch to 5w30.and if you haven't decided on oil yet i'd suggest mobil one.i've used it for almost as long as i've had my truck and my engine has hardly any wear from what i can tell.you can also run synthetic oil for 7,000 or more miles between changes too which helps justify the cost of mobil 1.

 

What weight synthetic do you use in your truck? I am only asking this because I hear a nocking noise in the motor during cold start ups. Sounds like the oil isn't in the right places if you know what I mean.

 

If your using 5w20 Motorcraft it is a blend of regular and synth.
Look on the label.

 

I have been using penzoil. It's cheap. 1.00 per quart. I dislike putting non quality oil into a vehicle I depend on day in and day out. I have been wanting to make the switch and now is the time I think.

 

The noise you are hearing is probably piston slap...

 

Welcome ! Make sure your oil filter incorporates an anti-drainback valve. Minimally buy a Motorcraft FL-820-S for $3 at Wally World or step up to a Mobil1 or K&N filter for $10-$13. Ford originally recommended 5W30 and now they recommend 5W20 for the same engine; both are fine. Mobil1 synthetic is a readily available, reasonably priced, quality choice. It comes in 5W30 and a 0W20 that is recommended to replace Ford 5W20.

 

I just checked out mobil1's website. They claim that 0W-20 is specifically designed for small cars and trucks that are high rpm vehicles. Honda, Toyota etc...

http://www.mobil.com/USA-English/Lubes/PDS/NAUSENPVLMOMobil1_0W-20.asp

maybee I should use the 5w-30???

 

Focus on the oil specification. The specification replaces the 5W20 and the bottle has a quote on it for replacing Honda and Ford 5W20. I've run Mobil 1 5W30 in all of my F-150s. My understanding is the engines were originally designed to run on this weight and meeting CAFE requirements caused the change.

 

Thanks for all the help. What is CAFE requirements? I spoke to a dealer. They recommended me to use 5w-30 as that is what they put in the vehicles that owners wish to change to synthetic.

 

I run the Mobil 1 in all my vehicles. Use the same weight as the no-synthetic. On multi weight oils the higher the gap between the first number and the second number the few miles you can drive before changing the oil. 5w30 as to 10w30. The oil has polymers in it that expand when heated. The larger the difference the more polymers it requires. The polymers break down over time, so the more it has in it, the fast the break down. Therefore you have to change the oil at 5000 miles verses 7000 miles.

Another thing about synthetic oils is that the oil molecules are basically the same size. Unlike petroleum based oils. This means you could run a lighter weight oil with a synthetic. That doesn’t mean I would recommend you do it, just that you could.

 

Amsoil 0w-30 in mine.

 

I would not change from the oil you have been using. I changed to the motorcraft semi synthetic and my passenger side head gasket started to have a major leak. Went back to regular 10w30 and the leak has just about stopped, will not even drip on the ground. Synthetic is much slippier and tends to leak or burn at a higher rate.

 

Not true. It just cleans away deposits that were blocking the leaks. 5.4s are known to have head gasket leaks regardless of oil type.

 

kinda proves the point that the synthetics just work better doesn't it...... lol

:santa: