Hello I am driving a '90 5.0 GT with a few mods and I was just wondering what oil would be best for the car. I was told Castrol GTX just regular old oil is good. I was told synthetic has detergents that can mess things up and that a regular cheap oil is better for the car? What are the best oils and recommended ones for the 5.0s? Does the 8cylinder restore formula do anything for the car really? (supposedly lubercates piston rings) What are some other good tune up/maintainence things to do on the 5.0?

 

AMSOIL is the best oil there is period.

 

What do you base that on? I think i saw somewhere they compared a bunch of different oils, but i cant remember what the url is.

 

Let's face it, petroleum based oils are all the same, brand to brand, they all come from the same place: the ground. The difference in oils is when you start talking about synthetics. Synthetics may break up deposits that have formed and MAY cause brittle gaskets to start leaking but there no way going to harm anything mechanically. Synthetics don't break down as easy as petro based oils. So you need to do some research and see which synthetic brand of oil has the best numbers and make your choice that way.

 

Actually, all oils are not the same. They can be refined differently, and namely the additives used to lubricate and protect are what is different and is what breaks down. Synthetic oils never break down. And I agree that Amsoil is amazing oil - very expensive though. I use Mobile1 - namely for the cost.

 

i like mobil 1 GOOD STUFF!!! lol

 

All modern motor oils contain additive packages which includes detergents, anti-wear additives, viscosity enhancers, etc. Synthetic oils have some major advantages over pertroleum based oils in that they don't break down under extreme heat as readily as pet oils but they can lose some of their additive package components over time, so you still need to change them on a regular basis, but not as frequently as petroleum based oils. You still should change the oil filter ever 3,000 miles or so even with use of synthetics to make sure the filter is still doing its job of cleaning the particulate matter out of the oil system. I have been using Royal Purple synthetic oil in my Stang for the last 10 years or so and it works just fine for me. Synthetics won't make seals leak unless they are already bad and choked up with the residue of the old oils which the synthetic oil may loosen up and remove as a result of the detergent additives, but this is a rare occurance at best.
Good tune up stuff includes changing the air filter, fuel filter, PCV valve, spark plugs, distributor rotor and cap, and spark plug wires if they are cracked and leaking sparks. Also check the timing and set it to factory specs to avoiding detonation which can kill the pistons if not corrected by setting the timing back. You should also drain and thoroughly flush the cooling system and replace the coolant with a fresh mixture of antifreeze and water. It also doesn't hurt to change the transmission oil and rear end oil if they have never been changed and if you have an automatic tranny, change the filter in it too when you change the fluid.
Hope this helps you out some.

 

how had is it to change the pcv valve and where is it located, thanks!

 

amsoil is guaranteed to a 1 year or 25k mile change interval when using a amsoil or hastings filter....if you used a piece of crap wix, fram, or purolator, you would have to change it every few thousand miles.

 

The PCV valve is on the end of the larger diameter rubber hose plugged into the back underneath side of the upper intake manifold. The valve is located at the back end of the lower intake maniford next to the passenger side head where it is inserted into a rubber grommet. Just pull on the hose and the valve will come out of its hole so you can replace it.