Synthetic pours out of my truck like a siv

[Triton46]

Everytime! I change the oil and used synthetic once...oil started leaking from the back and the oil pan. I switched back to dino and no more leak. This time I tried Valvoline Durablend and after 3000 trouble free/leak free miles I came out this morning to find a leak.

Question: the round houseing where the fan prop is located. Is the bottom half part of the oil pan?

 

[MyExpWork]

On older engines you shouldn't really run synthetics. Thats the reason for your leaks. I don't know the exact details, but sythetics will do that on older engines and older seals and gaskets.

Brian

 

[gijoecam]

Sounds like the front main seal is shot.

A synthetic oil should not leak any more than a dino-oil... early synthetics didn't contain any additives that waused the seals to swell like dino-oils do naturally. Therefore, the seals would loosen up and it would leak. It's not the oil causing the leak, it's the seal wearing out. Modern synthetics are supposed to contain the additives that swell the seals (the proper term excapes me). I ran synthetic in the 93 Probe GT I bought with 93,000 miles on it, and never had any leaks because of it. (Incidentally, it was Mobil-1)

I dunno... just my .02

-Joe-

 

[aldive]

Originally posted by MyExpWork
On older engines you shouldn't really run synthetics. Thats the reason for your leaks. I don't know the exact details, but sythetics will do that on older engines and older seals and gaskets.

Brian

Really? I have run synthetic oil in many trucks with up tp 300k miles.

 

[410Fortune]

you SHOULD run synthetic oils in every single engine you own, regardless of miles, if you ask me. But then again I;m **** when it comes to vehicles, I spend a ton of $$$$ for Mobil one synth and change it every 3500 miles..but hey my truck has 230K miles on her and she's never been tougher or run better......My original 2.9L engine had 180K on it when I yanked it out in favor of the 4.0 and it still ran hard, harldy showed any signs of physical wear inside (surprise, surprise, typical Ford workhorse cologne V-6) and I always ran synth.

PLus with synth lubein my engine, tranny, t case and rear diff I gained almost 3MPG (if my math is correct) and that will pay for itself real quick....

 

[gorilla]

Synthetic oil seems to work well on import engines like Honda engines and the like. Those types of engines has smaller clearances for all the internally lubricated parts. Ford engines, especially with high miles will almost garantee to leak beak the seal break down, loosen up and the clearances on the internal parts get greater. If you are going to use synthetic, you need to start using it when the engine is fairly new. Running synthetic for the long haul seems to really pay off! Either way you go, frequent oil and filter changes is still the key.

 

[aldive]

Originally posted by gorilla
frequent oil and filter changes is still the key.

And how do you define frequent?

Thanks.....

 

[dogfriend]

depends on the seals

I have experience with two Ford trucks using syn oil.

1. 1989 Ford Ranger 2.9L - Bought new, changed to Mobil 1 at first oil change (3K miles) Sold at 125k miles last year. No problems - BUT it did leak like a sieve (starting around 30 - 40K), especially from the valve covers which I replaced 2 times - 1st @ 50k , 2nd @ ~90k. Those gaskets were cork by the way which was probably considered state of the art in the 50's. One advantage of syn oil is that it is easier to clean off of the driveway . Never any sign of oil burning, but hard to tell after 100k because of the leakage rate.

2. 1997 Ford Exp 4.0L OHV - Bought used @ 32K miles, switched to Valvoline Syn @ 36K miles now have 78K miles. No sign of oil leaks so far. No sign of oil burning so far.

My opinions based on my experience and knowledge/background:

Newer synthetics may have better formulations for seal swelling than before (probably true)

97 engine built with better gasket and seal technology than 89 engine (definitely true for Ford V6)

Loose engines may leak (and burn) more oil when using synthetics (true because of the molcular properties of synthetic vs. "natural" oils - the molcular chain length is more consistent for syn oil but shorter on average so they can squirt thru gaps more easily)

Conversely, tight engines will usually burn less oil with syn oil for the same reason (the super short molcular chains in "natural " oil will burn off quickly - and the oil will break down sooner than with syn oil)

The only vehicle that I would not use syn oil with is one that already had a bad leak or bad burn problem (too expensive) Otherwise I think that the benefits outweigh the downside.

 

[Triton46]

My mechanic quoted me $300 to change the lower and upper intake manifold gaskets. He is really good and will do some engineering to the parts to get a better seal.

Is it expensive to get the front main seal replaced?

These parts were leaking prior to the change, just not as noticeably. I drive 140 miles a day (all highway at 70 to 80mph) and hit 5000 miles (my change interval) usually around every 5th week. I have noticed that by the time I hit 4000 the engine is really sounding rough, after the oil change is quiets down. The Durablend has kept the engine alot more quiet than with dino oil.

 

[AgExplorer]

A couple of items of note about synthetic motor oil:

1) Synthetic motor oil (those with a 100% PAO basestock) has a natural detergent action that will clean the deposits left behind by dino oil. These deposits will help weak seals and gaskets not leak. As the synthetic clears this gunk, leaks do appear. The motor oil does not "cause" the leak, it just exposes the weak seal or gasket.

2) Synthetics flow more easily than dino oil. Because of this, they leak better. Synthetics are able to get through smaller areas and more oil flows through a weak gasket or seal.

Semi-synthetics typically have less than 5% synthetic in the blend. You're paying a lot more for just a tweaked dino oil. There are no advertising regulations that define how much synthetic has to be in the formulation to define it as a "synthetic blend". So, go straight dino or synthetic.

I hope this helps explain what happens when someone switches to synthetics in an older vehicle. Synthetics are highly beneficial in older and newer vehicles because they run cooler and protect better against wear. If an engine runs cooler, the gaskets and seals will last longer. Less wear means the engine will perform like new longer. Many have also reported getting better fuel mileage, sometimes as much as 15%.

 

[MyExpWork]

ALDIVE,

It was my opinion and experience that on older engines where you have formally run the regular stuff, switching to synthentics will burn more oil because of the better protection that the synthetics will give. I can't remember the actual phrases or terms of why, but I have had several cars with over 100k miles. I tried swithcing to synthetics in two of them and they both burned a quart of oil between oil changes and leak more. With the regular I did not have this problem.

This was about 10 years ago so maybe they have changed them now.

Brian

 

[SteveVB]

What seal are you talking about.

The crankshaft seal at the front? Or is it leaking from the pan. The pan gasket is one piece that uses a blob of silicone at the corners.

Hopefully its the crank seal- pull the belt, and the crank pulley, and pry out the seal. Make sure they check the crank hub for wear.

On the intake gaskets get the Ford gasket - dont mess with aftermarket stuff. What is he going to engineer to get them to fit better? Unless the surfaces are damaged or not flat just get the right gasket, make sure everything is clean, clean, clean, and use sealant in the correct locations, and follow the factory torque values.

Good Luck

 

[410Fortune]

He's not gonna engineer anything, he's gonna do a good job and scrape off all the old crap, get it nice and clean, then use some GOOD gasket sealer so it wont leak. There is this grey stuff, it'sgot granuals in it,, and it will stop any 2.9L or 4.0L from leaking around the valve covers/intakes I cant remember the name of it...

OH and the cork gaskets on the 2.9L will never work, you are better off with no gaskets and a ton of gasket maker. Fel Pro made a special gasket to fix these leaks, the same gasket is available for the 4.0 I believe. They worked! Even with my chrome valve covers (2.9L) which are prone to leak, the blue Fel Pro's sealed them up!

If you own a Ford Cologne V-6, get used to oil leaks, it happens. I have mine slowed down to a few drops every night and that is pretty damn good for a stock 93 OHV with 80K on it....a little silicoln onthe oil drain plug, re-tighten the oil filter mount now and then, and just plain ignore the valve covers and front main seal....

When I rebuild this 4.0 that is when the leaks can be eliminated.......

If you run sysnthetics and you think it causes more leaks, try adding some Lucas "honey" oil addative in there, it is pure petroleum oil, thick as goo, works AWESOME. I'm a firm believer in Lucas, I got a TON of compression back with a quart of this stuff on my old 180K mile 2.9L...

 

[dogfriend]

agree with 410Fortune

One point that I was trying to make with my earlier post was that it depends on the engine. I had lots of oil leaks with the 2.9L, but I don't believe that it was necessarily due to using Mobil 1, it was due to the poor gaskets and seals of that particular engine.

The 97 4.0L engine appears to be much improved, especially the stoutness of the cast alum oil pan compared to the stamped steel one on the 2.9L.

 

[410Fortune]

Yeah isnt that funny! Ford finally got the 4.0L to quit leaking so bad after 7 years of production!!!!

Dont be surprised if your 97 develops the same front main and rear main leaks after 80K miles or so.

Heck how many engines over 50K miles have you seen that dont leak oil? It;s normal!!!! It lets you know everything is working!!

 

[aldive]

Originally posted by 410Fortune
Heck how many engines over 50K miles have you seen that dont leak oil? It;s normal!!!!

Well, I can name 5 right off hand, a 68 Mustang 302 with 250k, a 1980 Ford F100 300 with 225k miles, a Chevy pick up 350 with 175k, Nissan 4 cyl pick up with 350k, and my Explorer with 65k.

 

[MyExpWork]

It must be nice to be so perfect

 

[410Fortune]

So youare telling me not one drop of oil leaks from any off those engines and they have never been rebuilt?

Any addatives used in those baby's?

The only one I ever owned thathad high miles that didnt leak was my 76 BMW 2002, all my other cars at least had oil coated on the engine, if not a few drops on the ground......

 

[aldive]

Never had any oil in the garage ( floor is concrete ), never had to add a single drop of oil either.

 

[SteveVB]

Get the Ford gaskets, they are a metal/rubber composite, Throw the cork and compostion gaskets away. Forget about large amounts of sealer. The valve cover gaskets need two drops of sealer at the head/manifold joint- THATS IT. The intake uses 4 spots of sealer. You need very, very little. Ford did get the gaskets right after so many years- use them and install them correctly. Make sure that the sealing surfaces are clean- lacquer thinner cleans nicely with no residue.