Dino to Synthetic and MMO same time?

[grizbait]

I just finished re-building the upper end of a 3.4L V6 GM motor - (96 chevy lumina van). Had 152K miles on it at the time.

That said, I have the same lower end, and I want to switch to synthetic and clean her out as best as I can. I've been running dino in it since I've owned it. I understand that synthetic will clean it out fairly well w/out any additives... or so I've read.

My plan was to dump the dino, add 20% MMO, 80% Synthetic Mobil 1 and then change the oil after 1000-1500 miles or so.

Is the MMO and synthetic switchover at the same time too much? Should I phase this out more? Any thoughts?

Thanks.

 

[ZR2grizz]

I think you'd be fine with/without the added MMO. I don't think the cleaning power of either combo is going to be super significant, but since is was the top end (LIM gaskets?) I would definitely do a short OCI or eve a couple to be safe.

GO GRIZZ!!!

 

[ADFD1]

The MMO and synthetic oil combo will work fine. You can do what you plan on doing, or try this. The nice thing about MMO is it can be safely added to any oil dino or synthetic, doesn't matter. You can start with a fresh fill add 1 pint of MMO, then add another pint about 1000 miles before you plan on changing your oil, your normal OCI. That should get the cleaning of the bottom end of the engine in good order.

AD

 

[chevrofreak]

As best you can would involve using Auto RX. I'd do a short OCI using conventional to clean any potential fresh wear metals out, then I'd run a bottle of Auto RX with some Castrol GTX.

 

[grizbait]

Originally Posted By: chevrofreak
As best you can would involve using Auto RX. I'd do a short OCI using conventional to clean any potential fresh wear metals out, then I'd run a bottle of Auto RX with some Castrol GTX.


That's pretty much what I've got going now... < 50 miles on current dino and out she comes. I will plan on doing auto-rx too down the road at some point...

GO CATS!... spank the Grizz

All in jest of course...

 

[grizbait]

Originally Posted By: ZR2grizz
I think you'd be fine with/without the added MMO. I don't think the cleaning power of either combo is going to be super significant, but since is was the top end (LIM gaskets?) I would definitely do a short OCI or eve a couple to be safe.

GO GRIZZ!!!


Ya - the infamous LIM - along with the 'distributor' o-ring, head gasket, timing chain cover gasket, both main seals... on and on... basically every gasket/seal in it. glad it's done... don't want to do it again any time soon!

 

[JHZR2]

I'd do exactly your plan. Great idea to do the early changeout. I might go slightly lower on the MMO percentage though...

 

[Rick20]

Why run a lower percentage of MMO?

 

[Nickdfresh]

I would either run just Mobil1 High Mileage 10w30, or add half a quart of MMO to Pennzoil Platinum...

 

[Rick20]

Short OCI, less than 500 miles as previously stated, get any break metal fines out. Then I would vote for ARX, good lubricity booster and will keep any break in hot spots from accepting oxidized oil deposits. Don't need a full cleaning dose. I would suggest about 4 fluid ounces as part of the total sump capacity, IMO.

 

[Nickdfresh]

BTW, I did add MMO to Pennzoil Platinum for the final 500 miles of an OCI. I cut open the filter and it did have bits of gunk in it. Whether this is the PP cleaning claims of sludge removal being genuine, or whether it was the MMO I can't say for certain, but believe it was a little of both...

 

[Greggy_D]

Originally Posted By: Nickdfresh
BTW, I did add MMO to Pennzoil Platinum for the final 500 miles of an OCI. I cut open the filter and it did have bits of gunk in it. Whether this is the PP cleaning claims of sludge removal being genuine, or whether it was the MMO I can't say for certain, but believe it was a little of both...


That would have been a GREAT test if you replaced the filter when you added the MMO. Then you would have had two filters to compare and cut open.

 

[bigmike]

If it were me, I'd keep the dino and use shorter OCI with MMO. Why change or pay more?

 

[c3po]

Originally Posted By: Nickdfresh
BTW, I did add MMO to Pennzoil Platinum for the final 500 miles of an OCI. I cut open the filter and it did have bits of gunk in it. Whether this is the PP cleaning claims of sludge removal being genuine, or whether it was the MMO I can't say for certain, but believe it was a little of both...


You are probably correct, and the reason I say this is because when I started using Pennzoil Platinum I noticed the oil came out darker when I went to do an oil change versus using dino oil.

A member on here recommended PP and I am very happy with this oil.

 

[ionbeam22]

Oil darkening could be a sign of sludge being removed, or it could just be that the particular oil likes to darken alot upon early use.

I would go with what ADFD1 said, and just use the straight M1 with 1 pint of MMO added and then add a second pint of MMO a few hundred miles before the next oil change. A slight overfill won't be harmful.

Using a 20% fill of MMO will change the bulk properties of the oil (at the very least it will drop top end viscosity by a grade). IMHO that viscosity drop is what makes the engine seem more "fun" when you have a 20% fill of MMO in the crank case.

This leads to the question of if you should be running an oil with a lower top end viscosity than recomended? Rislone engine treatment is also supposed to be a good (slow/gentle) engine cleaner, while not affecting the bulk properties of the oil.

The only other additive I like is the Lubro-Moly MoS2 Anti-friction which you can get at AAP. It is made from colloidal MoS2 and the dosage is 50ml/quart and $6/300ml per bottle. In my experience it makes the engine start and run smoother.

I'm currently using Valvoline Syn 5w30 with 1 bottle of Lubro-moly, and quite happy with it.