Confirmed- don't switch back to regular oil after high mileage

I have been buying my oil on Amazon. If you are a little patient I find Mobil 1 ow-20 for less than 20 bucks for a 5 gallon container. Free shipping with prime. It's not always that cheap you just have to keep waiting for the right price. Amazon is a little sneaky on their pricing anyways.

 

What, ZDDP or detergents?

My feeling on high mileage oils is that unless you have an issue you're trying to solve with them (e.g. extra swelling agents), there's no reason to use them. The problem for me is once you start (and thus swell said seals) you usually can't stop since the swelled seals being swelled get worn in the swelled condition and letting them no long be swelled isn't swell.

 

ZDDP isn't in newer oils and if it is it is in such small amounts that it doesn't really help any. You have to go to the likes of AmsOil, Royal Purple, etc to get the zddp. That additive was much more important back in the day with hydraulic and solid flat tappet cams.

There are many additives besides those 2 you mentioned. But the extra detergency is a bonus. The binding agents, additives to help reduce friction, they use a higher tier base oil, etc. I have sat through probably 40+ hrs of talks with oil gurus in talking oil and learning yet I still feel somewhat inadequate in knowing everything there is to know.

The coolest was touring the castrol plant and getting to talk to the guys in charge of the oil JUST for John Force racing. All the race teams get proprietary oils from whatever manufacturer is their sponsor and the stuff they do seems like JFM to me!

 

I always stocked up as well. Now I have 4 gallon jugs of 10w30 synthetic and no motors that use it. Well the lawn tractor does so it lives on full synthetic now and gets changed twice a season just to blow this stuff out.

 

Yup....been there before with the front main seal. Not sure what caused mine to go. But when the oil comes out there it hits the pulley and gets slung around just about every where. It's typically pretty identifiable by the radiating splatter marks. Timing cover will obviously start MUCH higher than the crank seal leak would so you would be able to tell the difference pretty easily.

I've heard putting too much oil in the filler neck can cause the front (or rear) main seal to go but I don't know how much truth there is to that.

 

I'm actually experiencing the opposite at the moment. I've ran dino for the last 30k and my dad happened to have some left over synthetic 5-30 from his old truck that he gave me. Since I've been running synthetic I notice a burning oil smell when I come to stop lights or in traffic. I've had the typical valve cover leak for a while now, but never smelt burning oil untill the switch in oils. I'm just over 170k.

 

This can happen a lot of it has to do with the difference in the additive package in the synthetics vs regular. I'd switch to a high mileage or back to regular.

 

Correlation is not the same as causation. It's very unlikely changing your oil will not make the seals leak. This is the sort of jumping to conclusions at unrelated correlations that has put lives at risk because of these crazy anti-vaxxers. This, right here, that's the same mentality. Just slow down and think about it before we jump to conclusions.

 

Also, just a thought, if 170k miles has compromised your seal through heat-cycles and flat out age to the points where it's allowing one oil to not leak (that sure, let's say was making it swell) while the other one leaks... wouldn't that just mean you should change your seals anyway? Regardless of oil type, they'll start leaking eventually, it just sounds like you're on the verge where a small difference in viscosity or swelling in the seal is the breaking point.

 

Haha having family that were and are in the pharmaceutical industry I am not a huge proponent of vaccinating for certain things also knowing the truth behind them gives you greater insight into why not to. Most anti-vaxxers are conspiracy theorists but there are some that know what they are talking about.


As I stated before the high mileage oils have additives that cause seals to swell now when you switch this can cause oil weeping, this came straight from the horses mouth from several oil maufacturers because the additive concoction is different the base oil is different. This is also true from using dino oil until you have higher mileage and then switching to a more performance oriented synthetic and getting some oil burning. Could this be a cause sure could it just be a circumstance yeah, but I tend to lean towards what the oil guys have told me.

 

Yes the additives that cause seal swelling are more of a stop gap and you should replace them regardless. At that mileage and # of heat cycles you are absolutely correct the seals will eventually become compromised and need replacing.

 

From my understanding HM oil doesn't really "swell" seals but rather conditions them to keep them pliable. This is why I'm using it, my truck never had a leak, but I'm using the HM oil to keep the seals in good condition. It's a ten year old truck, and rubber does harden over time.

It sounds to me like the OP has the infamous timing cover leak, which would have absolutely nothing to do with the type of oil being used.

 

Oil pans leak. The gaskets are not lifetime gaskets. You got 170k out of it with no leaks. Some vehicles don’t even get that so be happy. Change the gasket and move on. My .02, HM oil is shit, just stick with synthetic and change the oil every 5k. Carry on with your life.

 

Yes and they do to a certain extent swell the seals. The main seal they are after for this is the valve seals but all the others are a side effect.

Yeah that is very true I concur about the seals. Why do you say HM is shit?

 

Some people are fucking hypochondriacs... if it's a leak, fix it. If your really concerned about the source of a leak, mix some UV dye in a quart of oil and add it the next time you change your oil and drive it for a while. Take a UV light and some yellow tint glasses and you will find your leak. Easy. A slightly seeping oil pan is not worth my time to drop and fix. Now if it has a steady stream of oil draining back into the earth then yeah I'll fix that. And 170k is pretty good on a stock gasket. Ive seen fords leaking at 15k miles. And at least you don't have to do the pan gasket on a g35.

 

"Verbal abuse" is a bit strong...

It's an internet forum, and folks don't usually play nice with someone who's been a member since 2014...with 39 posts...and still has to be asked to upload photos to properly frame their "call for help" issue.

It has been mentinoned a couple of times in this thread, but...



Pictures really do help, and are potentially worth 1,000 words of "abuse."

People are really here to help, you just need to prepare accordingly and lower your expectations...a lot.

That said...see if you can locate the actual source of the leak, determine it's actual rate (seep, drip, flow) and address accordingly. Returning to your originally run HM oil should provide you with peace of mind, but the leak is potentially your biggest issue, and solving it should be your focus.

If this were my scenario...I would clean the sh1t out of my engine, top off my oil supply, drive the truck for 100 miles, grab my favorite headlamp and determine the real area of the leak.

 

This thread has lost me. I don’t even know if it’s synthetic oil that is good or bad, or if conventional oil is good or bad. Or if both are bad and we should be using vegetable oil now to prevent leaks.

 

Leaks are bad...

 

No oil is "bad" unless it's the cheap bottom of the barrel crap you get at the gas station. There is just a lot to oils and they all have their pluses and minuses. You just have to research the different types more so than forums and what they actually offer to find what best fits your needs and vehicles needs. They have different formulations for many different applications and needs.

 

You should read up on what oil to use in motorcycles. That's a whole other can of worms. Being that the engine and transmission use the same oil and it's a wet clutch car oil(with anti-friction additives) can cause the clutch to slip. Plus when your engine redlines at 13,500RPMs.....