Mobil 1 and oil seepage......

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May 6, 2003
I am having seepage through my valve cover gaskets and cam caps. I have been running M1 since shortly after purchasing my 4-Runner. The vehicle was purchased at 56,000 miles and I assume dino was run. I did quick oil changes with dino to clean internals when I purchased vehicle. I then started running synthetics M1 at about 65,000 miles. No leakage at all until M1.

I understand that M1 is cleaning residue and is exposing areas that were coated with dino on the seals. Shouldn't the conditioners in M1 condition the seals and eventually stop the leaks?
Is M1 lacking this?

I am at a loss as to what should be done. Would switching oils do the trick, Amsoil, Redline, GC.? I would hate to go back with dino.

I could replace the gaskets but I will have to pull intake manifold!

Any suggestions?


Daily Drives
-2003 Toyota Tacoma PreRunner XtraCab, Impulse Red, Peppy 2.7 Liter 4 Banger, Running Mobil1 Synthetics SS 5W-30.
ODO 5400 Miles.
-1995 Toyota 4-Runner, Evergreen, 3.0 V6, Running Mobil1 Synthetic SS 10W-30.
ODO 82500 Miles.
From what I've read here the thing to do before switching is to go thru an Auto-Rx cycle to get the seals ready for the synthetic.

That being said, as you point out the synthetic isn't making the engine leak, but rather is cleaning what was plugging worn gaskets in the first place.

Personally I'd change the gaskets, but the Auto-Rx sounds like the easier route.

You ask a good question about the M1 eventually swelling the gaskets. It should, but I have no idea as to how long that might take.

[ October 30, 2003, 08:27 PM: Message edited by: Randy ]
I'm not sure the Auto-Rx will help. Hoefully others can confirm Randy's suggestion. But its a cmbination mainly of dissolving sludge but mostly I think its just that synthetic can get thry smaller spaces. Also it could minor differences in seal swell/shrinkage properties.

I believe the seepage would be reduced by going back to dino. Esters have more seal swelling so its possible (but not probable) that switching to say Redline or 0W-30 Syntec (CG) could help. I would suggest just snugging the gaskets just a tad. Torue wrench desirable.
Thanks for the replies!

Which synthetic has the most esters? If esters will do this maybe thats what I need.
Mobil 1 has nothing to do with leaks, is not too thin, does not cause engine knocking or other engine problems.

M1 will clean junk out from other oils and then leaks will occur.

Oils with high ester content are Redline, Amsoil S2k and GC.

[ October 30, 2003, 10:55 PM: Message edited by: buster ]
Mobil has something to do with leaks since it never leaked until Mobil was used. That being said it proves that the Mobil is doing some cleaning and exposing weak areas in the seals. The big question is whether the leaks will subside over time?

By the way it only drips one drop or so a day thats why I consider it more of a seepage effect.

I have considered using RX.
Well I never have had additional leakage with Mobil, but I have known others like Amkerr who have had increased seepage when switching to Mobil 1. I know in particular "Spector" on this board has experienced thie in some of his vehicles.
This is my thoughts on this. Complaints, suggestions, arguments welcome!

I will continue with M1 until my change which is February 2004. The leakage will be monitored. If the leakage slows to nill I will continue running M1. If the condition remains same or worsens I will try another synthetic, Amsoil, Redline or GC.

The worst case is I will pull intake manifold, change gaskets and do a valve adjustment if necessary.
Sounds good. If it leaks though-don't bother with Amsoil. It will probably leak like Amsoil. Only difference is that Amsoil is a little thicker. Redline or GC time
Al I am leaning towards GC after this run. I may change this batch out sooner rather than later. This interval went in 9-7-03 and was due to come out in March. I will change it in January.

Originally posted by Amkeer:
Al I am leaning towards GC after this run. I may change this batch out sooner rather than later. This interval went in 9-7-03 and was due to come out in March. I will change it in January.

Too bad your 3.0L isn't one of them that was part of the head gasket recall. The dealer would have fixed this when they did the head work.
I don't think the cam cover gaskets are that hard to change and I'll bet it's going to be hard to find an oil to stop the leaks now that they've started.

My 3.4L Toyota motor isn't leaking yet at 56K miles though it's had M1 5w-30 in it for the last 30k miles.
jsharp, agreed! I already pushed the head gasket but Toyota says my vehicle isn't effected by the recall.
I tried!
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