cookiemonster

I noticed that Ford recommends 5W30 for our V6-ers, yet recommends 5W20 for the GT ... 5W20 is supposedly "generation 3" oil, while 5W30 is "generation 2" (and 10W30/40 is "generation 1") ... and 5W20 supposedly improves gas mileage over 5W30, yet this page states that using 5W20 as opposed to 5W30 will shorten engine life by 30% ... and it goes on to say that 5W40 will significantly extend the life of an engine ...

Can/should we V6-ers also use 5W20 or 5W40 instead of 5W30? If we can, would it void the warranty? Can a dealer easily find out what viscosity we are using?

[sm=burnout.gif]

fazm

just use the 5w30, the 5w20 is too thin, and the 5w40 is overkill.

Dineau

I was told when asked the same question to my mechanic that the 4.0L have a different configuration on the timing chain binders and if you use thinner oil they will become noisy...

birdoffire7

I agree about 5w20 being too thin. Use at least 5w30 for the protection. I have, however, used a full synthetic 5w50 in another car of mine that currently has 310k+ miles on it since I've had it. I'll be using the 5w30 syn blend at least until my warranty runs out...

Pimpin Pony

wow, 310k miles aint no joke!!! would it bea bad idea to use something with that kind of viscosity say once we hit like 80k? or should we still use 5w30? by the way what brand do yall recamend? I wanted to go with Royal Purple, but I couldnt locate any in my town, so I went with Mobil 1 and when I talked to one of my friends that used to be a mechanic, I mentioned changing to Royal Purple possibly for my next oil change and he told me not to change up brands, to just use one kind of oil and thats it. What do yall think about that?

birdoffire7

The 5W50 I use in the other car is Castrol Syntec Full Synthetic. I'm currently using the Castrol Syntec Blend 5W30 for two reasons:
1) I've been using Castrol sythetics for almost a decade with no issues what so ever. (NOTE: I've never used Castrol non-synthetics ever, so I can't speak for them.)
2) The car came with sythetic blend in it and suggests to use it in the owner's manual. After the warranty expires, I will most likely change to full sythetic. Mobil 1 is a renowned brand also, just have never used it. You should be fine with it.

As for mixing oils- all oils mix together just fine. You can mix a synthetic with a regular and you can mix different weights together such as a 5W30 with 10W30. It all blends together, but the overall properties change. I don't recommend mixing the different weights together though, due to if you throw a quart of this and a quart of that in the car, you really don't know what properties the combined mixtures end up having. I'm just saying it won't inherently hurt your car and the oils won't explode or anything like that. Definately stay with what the manufacturer recommends, which in our case is 5W30 of course. I assume what your mechanic is telling you is to find an oil you feel comfortable with, that works good with your car, and stay with it. There's no point changing something that works fine.