Mobil 5000 CLEANS (maybe too well)

[bubbatime]

So I got about 62K miles on my 2005 Tacoma. It has always had oil changes at regular 3K to 5K intervals. It usually gets whatever oil is on sale or bogo, i.e., GTX, yellow bottle, Valvoline White bottle, QS Synthetic a time or two, etc.

I just changed out the QS synthetic 5w30 for a fresh batch of Mobil Clean 5000 5w30. I then drove the car 500 miles in two days and noticed that it sprung a valve cover leak. This engine has never leaked any oil and I am not sure how this oil caused a leak but I am a little concerned. I might drain it and try a high mileage oil and see if the leak goes away. Maybe this stuff DOES REALLY CLEAN??

 

[saberz]

I doubt the oil was really the cause for it, sometimes changing between brands and formulations results in a small removal of buildup(if any). It could have also been an issue that just came to your attention(was going to happen and it did happen).

MC5K is a great oil.

 

[bubbatime]

I did check to see if it was something I did that caused the leak, but I did put the oil filter and oil cap on properly.

 

[saberz]

Could just be the swapping of oils. I am sure someone else will post other suggestions and possibly a more concrete answer.

 

[Bill in Utah]

I really doubt Mobil 5000 caused the leak. It prob was going to happen either way.

I LIKE Mobil 5000. I feel its Mobil's best values in oil! I'd leave it alone and see how it develops. Check the cover nuts and see if it goes away...

I'd NOT go the HM oil direction...

Take care, Bill

 

[dave1251]

I agree with Bill try a couple of OCI's with a HM oil. If you want to spend the money get the leak fixed.

 

[daves87rs]

Originally Posted By: Anies
I doubt the oil was really the cause for it, sometimes changing between brands and formulations results in a small removal of buildup(if any). It could have also been an issue that just came to your attention(was going to happen and it did happen).

MC5K is a great oil.




+1

 

[number_41]

Bill--Why no recommendation for a HM oil?

 

[saberz]

I think in this case swelling with a HM would do more harm than good. You need to fix the problem at hand as the HM will be a bandaid to a possibly bigger issue if you ignore it.

 

[shrooms]

Originally Posted By: dave1251
I agree with Bill try a couple of OCI's with a HM oil. If you want to spend the money get the leak fixed.


Bill said "I'd NOT go the HM oil direction..."

 

[brandini]

Or you could FIX the problem!

My favorite quote:
Why do I not look busy? Because I do it right the first time.

 

[J. A. Rizzo]

I agree with Bill - probably had nothing to do with that particular oil.

Whatever you do, don't just torque down the valve cover bolts to tighten it up. Friend just did that and split the gasket in two places and bent the valve cover. Now he needs a new valve cover and a new gasket. Hopefully it won't leak any more after that!

Or you could dump in a quart of Prolong, which would enable you to fill the crankcase with sand and continue driving. That should stop up the leak.

 

[mechtech2]

Of course check the valve cover bolt torque. But take it easy!
You can over tighten them and break them off or warp the cover, in some cases.

Check your PCV system. Higher internal pressures will result and leaks can occur at gaskets or seals.

Are you overfilled? Is this leak continuous or maybe from spillage?

And lastly,switching synthetic oils are not supposed to cause leaks, but they can and do.Sometimes, bordering on unusual. Not just from cleaning, but who knows/whatever. I have seen it in the shop a bunch of times.

 

[Bill in Utah]

Originally Posted By: number_41
Bill--Why no recommendation for a HM oil?


Not really a fan. 61k miles on his engine and if it DOES have a "issue" then take care of it.

His problem is mostly likely a loose nut on the valve cover. When I said to tighten them up means to check that they are not loose.

I may try Valvoline Maxlife just to see what the big deal is on my 122k truck. Don't have any problems (it does have a slight leak on the rear main) but just to see IF it does any thing special. (now that I know that I don't have any coolant issues)

But to fix things that are simple to fix like a cover gasket? Pass on the HM oil.

 

[StevieC]

You must have Iron in your Head Gaskets... XOM doesn't like iron and thus you are having a leak you should never ever use Mobil-1 products again!

Probably coincidental.

 

[number_41]

Thanks, Bill. I have just tried Valvoline MaxLife semi synthetic (red bottle) on my '89 Ford F-150 5.0 L, 107K miles and after 1200 miles it appears to have stopped a leaking rear main seal (small leak since @ 20K). I know the factory Ford oil pressure gauge is not like a good Stewart Warner mechanical gauge but it's readings have decreased slightly over the years. After the MaxLife the gauge has increased slightly to what it was when new. Am thinking of switching my Subaru OBW 2.5 to MaxLife 5W30 at 60K also (at 41K now on a 2008). This site seems to report it's a very good oil.

As for the original question here I agree with you.

 

[RedOak]

I am using MC5K in my 01 Sunfire after a steady diet of Carquest 5w30. The valve cover has had a slight leak since I puchased the car over a year ago. The mobil dino has not increased the leak a bit. I have to take the time to take the valve cover off and fix the gasket issue. MC5K and PYB are two of the better conventional oil's out there. It is hard to find a bad one.

 

[Falcon_LS]

Funny you mention this. I recently switched to PP 5w30 and noticed my passenger side valve cover was leaking slightly - which was replaced less than 20,000 km (12,500 miles) ago.

I just dumped in a bottle of Liqui-Moly Motor Oil Saver to sort it out and tightened the bolt (which did turn out to be a bit on the loose side).