Car Oil Question

[Franko]

I have a 2001 Toyota Sequoia that has always had synthetic oil used in it. However, I just discovered that for the last few oil changes, my wife switched back to mineral oil. I have always heard that once you use synthetic, you have to keep using synthetic. Is my truck in any danger?

[Pale Rider]

I have a 2001 Toyota Sequoia that has always had synthetic oil used in it. However, I just discovered that for the last few oil changes, my wife switched back to mineral oil. I have always heard that once you use synthetic, you have to keep using synthetic. Is my truck in any danger?

No, your truck is still fairly new, with new technology as far as engine seals are concerned, back in the old days the synths would leak past the higher mileage hardened seals.
Don`t worry about it, why did you switch back? good synth`s have longer drain intervals, if your using dino oil again make sure you change it out at 3000 miles...PR...

[Snkypete]

There is absolutely no harm in switching back/forth.

The "problem" with synthetics is that on high mileage cars if you then switch to synthetic they have better detergents and if there is any sludge built up - it will be cleaned away and this usually exposes existing leaks that were blocked by the sludge.

Assuming the vehicle has always been well maintained, you will be fine either sticking with dino or going back to syn.

[Franko]

I didn't intend to switch back, but when I got married, the wife took over the job of getting oil changes since she doesn't work. Apparently, I did not tell her to ask for synthetic oil Anyway, the truck has 105k miles on it. Should I swith back to synthetic?

[Pale Rider]

I didn't intend to switch back, but when I got married, the wife took over the job of getting oil changes since she doesn't work. Apparently, I did not tell her to ask for synthetic oil Anyway, the truck has 105k miles on it. Should I swith back to synthetic?

I`m surpried snky technically you would use Amsoil`s flush when going from dino oil to a quality aynth.
Franko, that is entirely up to you, do you plan on keeping the truck longer?...like another 100,000?...PR...

[Snkypete]

On a car with that many miles I would not bother using the flush...just my opinion.

[Franko]

I plan on driving it until the wheels fall off. It is still in great condition, not one mechanical problem, and most importantly, I have no car payment So I want to make sure it lasts a while.

[Snkypete]

Personally if that is the case I would use Mobil1 and change it every 5-7k/miles.

[Franko]

Thanks Pete. Will do. That's what I was running until I neglected to tell the wife to ask for synthetic

[Pale Rider]

Personally if that is the case I would use Mobil1 and change it every 5-7k/miles.

I agree! cheap insurance enough!

The only reason I would flush, is that whatever residual dino oil is in there would not last compared to the duration of the synth, but we`re prolly talking minimal here, anyway, I would prolly change the first synth cycle at around 3500 or so...PR...

I also didn`t know the mileage of Franko truck...