Motor oils

theterminator93

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1997 Thunderbird 4.6, 1998 Mark VIII LSC
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This has been beaten to death elsewhere, but here it's still a new topic! :biggrin:

I've been using Valvoline's full synthetic with high mileage additives in the cars for a good while - changing with an FL-820s filter every 5000 miles. I just noticed a new "higher" mileage formula in a black bottle - 150k+ miles instead of 75k+. However it's a synthetic blend instead of a full synthetic, which gives me pause... but I was thinking I'd give it a try anyway. The Mark VIII loses about 1.5 quarts between changes and I wonder if the extra seal conditioners might do the old engine some good. I've never been much on the various "cure all" additives that come in pint-sized bottles.

As to weight, I've been using the originally spec'd 5W30. I know in 2001 Ford declared that all 4.6s were to use 5W20. I used it a few times and don't recall noticing much difference. Supposedly it was to improve mileage slightly to help with CAFE standards, and some others claim it helps with getting pressure to the heads on cold starts. Wasn't sure what the consensus was here on that, so I figured I'd ask.

At one point on TSTSNBN, someone suggested that I try 0W20 in the 4v motor on my 96 to reduce startup valvetrain noise. I tried that... then the engine spun a rod bearing 400 miles later. :beek:
 
1.5 quarts in 5k miles isn’t bad. In lieu of high mileage oils or snake oil additives I’d just run a quart of Mercon through the system for 50ish miles before an oil change, does the same good for seals as any of them, and cleans the engine. Blue Devil works pretty good too, I had a leak from a fresh pinion seal and adding just a mere 2 ounces to the diff oil stopped it.

I too spun a rod bearing almost immediately going lighter, the Ford recommended 5w20 no less. My Dad’s newer Mazda 6 uses the 0W20, every time I change it for him I wince.
 
It all comes down to viscosity vs film strength. If it's too thin, it won't prevent contact. 5w30 was recommended to be thin enough to get to the cams quickly, but thick enough to hold up to the stress. We have really tight stock clearances, and they don't grow much. The 97 mark motor I took apart was close enough to oem tolerances to be new. After 158k miles, it had worn (0.05mm. That car had one imrc stuck open, one stuck closed. the whole ass end was in the trunk. Permanently, lol. My old Subaru loved 20 W 50; I have heard that 10w40 will kill these quick, but IDK. I'm not going to try. :)
 
My 2000 Continental, which was my 1st car in the US, systematically lost one quart between oil changes, i.e., one quart every 1,500 miles.

On any subsequent cars, I didn't notice any loss. The Thunderbird gets an oil change every 5,000 miles with 5W-30. I used Valvoline as well as Super Tech, both full synthetic, and the Valvoline seemed to produce smoother operation - though I may be imagining things (?). My first oil change was Motorcraft blend, and the switch to Valvoline full synthetic seemed to produce a noticeable improvement in fuel economy (though it coincided with the removal of the silencer and addition of the front underbody shield).

I never used any kind of oil branded as "high mileage" because if it ain't broke...
But I did wonder about it: should I use it just due to the engines age?

Now let's collectively knock on wood!
 
High mileage for these engines is 500k. All my cars but the Tbird used about a quart every oil change. I use castrol syntec synthetic, 5W20.
Lazarus originally had quaker state in it when I got it; IDK what weight, but it was only in a week. But the oil always comes out black.
I'm curious to see what his engine measures at 500k miles...
 
It all comes down to viscosity vs film strength. If it's too thin, it won't prevent contact. 5w30 was recommended to be thin enough to get to the cams quickly, but thick enough to hold up to the stress. We have really tight stock clearances, and they don't grow much. The 97 mark motor I took apart was close enough to oem tolerances to be new. After 158k miles, it had worn (0.05mm. That car had one imrc stuck open, one stuck closed. the whole ass end was in the trunk. Permanently, lol. My old Subaru loved 20 W 50; I have heard that 10w40 will kill these quick, but IDK. I'm not going to try. :)

Modular are happy with 10w40, heck a lot of Crown Vic taxi fleets we’re maintained with Rotella T4, so if it killed them it wasn’t quick. That said I wouldn’t run that weight, 5w30 is just right
 
I'll advise reading your current (actual) oil pressures both cold and hot before making any viscosity changes. Otherwise, you're shooting in the dark. For a stock 4.6L, 0W-30 or 5W-30 is the safe bet. I would not suggest a XW-20 or a 10W-XX oil. The former is going to reduce oil pressure when at operating temp, the latter will reduce flow at startup.

As far as the "high mileage" oils go, they're typically just adding a seal conditioner into the mix. If you have an engine that is starting to leak or the valve seals are starting to go, it can help.
 
As far as the "high mileage" oils go, they're typically just adding a seal conditioner into the mix. If you have an engine that is starting to leak or the valve seals are starting to go, it can help.

But is it really high mileage, or high age? What about a 27-year-old car with 55,000 miles?

Should I use high mileage oil, even as a preventative measure?
 
Well, judging from the transmission seals, I'm guessing Lazarus's valve stem and other seals are hard and crumbly, lol.
Rod, didn't you mention the high oil pressure being over 100psi cold?
 
87B97885-B30D-4A37-9B0D-862876ECE611.jpeg

I do what the owner's manual and maintenance schedule booklet said to do in 1995. Motorcraft 5W-30 conventional and filter at the dealership every 3,000 miles or twelve months, whichever comes first. Everything else gets done based on the Severe Duty schedule.

I'm too sore most days to change it myself but too stubborn to let anyone that isn't a factory-backed dealership touch any of my cars. The FordPass points also rack up real quick, especially considering that one of my three Fords gets driven at least 50k miles a year. I usually get enough points for at least one free oil change a year.

Fun fact for those with a 3.8L, this is what my 1995 owner's manual has to say about the correct viscosity for those engines.

F7B80A6E-530F-4D8F-92E3-8D7E1453662D.jpeg
 
That's a lot of cash over the years to have someone change oil. :) $25 at walmart for synthetic, 3.50 for a filter from ra. I'm a cheap bastard at heart. :)
I seriously looked into getting a 55 gallon drum of oil; the hangup was my lack of a loading dock, lol. It was cheaper than walmart, tho.:)
 
If I ever take any of my cars to Walmart for any reason, it means my mental condition has degraded to an irreparable state beyond any hope of recovery.

As such, I would request that someone on this forum shoot me immediately.
 
I stick to Pennzoil. Ive run mobil, Castrol, Valvoline, and Quaker State as well.

Castrol seemed over priced. Didn't notice a difference in temperatures or pressures. Mobil I like but that's just cause I'm biased from my family. It's over priced too. I never liked Valvoline. I've ran it in the old green Dodge and the white bird. Didn't like how the engines sounded with it, like it rattled worse. Quaker State didn't impress me but it didn't make me not like it either. I'd use it in a pinch.

I landed on Pennzoil at first due to cost. A big name oil for less than $30 is hard to beat. I ran it first in the Honda (5-30) when I was traveling 70 miles a day. Car ran great and seemed to run smoother and quieter than when I first got it. Which became the theme for every other vehicle I use it in. The white Dodge runs Pen 5-40 and runs great. The torture test, obviously, has been the red car. It's had Pen 5-30 since I started racing it. Hasnt let me down yet with how hard I run the car. Good pressures, 11 psi idle (190°) and 59 psi 6500. And is easily cooled through the stock explorer cooler. Pretty cool watching to pressures rise as the temps drop on a cool down lap.
 
I never liked Valvoline. I've ran it in the old green Dodge and the white bird. Didn't like how the engines sounded with it, like it rattled worse.

Interesting!

I liked Valvoline synthetic after the switch from Motorcraft blend. I felt the car was quieter and smoother. I ran it for two oil changes. After that I wanted to try Super Tech to see what an inexpensive oil would do, and it doesn't seem as smooth.

I may give Pennzoil a try next. I'm curious now.


Unrelated, but Valvoline seems to be good for Maxlife ATF, too. I read lots of positive reviews.
 
I used to get oil and my filters from there; it was about $23 for a 5-quart jug of full synthetic (Mobil 1 or Valvoline) and $5 for a filter, but last time I was there they wanted $28 for the oil and $9 for the filter. It's $30 for both from Amazon, and I'm a cheap tart, so... :roll:

I used the Valvoline MaxLife ATF (red bottle) for a while. I guess it's not Mercon V compatible - Mercon LV, though. I didn't kill any transmissions using it, but YMMV. I go out of my way now to get a case of Motorcraft MercV bottles. :smile:

I kinda miss my 94; I had converted the oil pressure gauge and it was enlightening to see it actually move around instead of just sit there at 12:00 all the time.
 
I buy Mobil 1 synthetic 5w30 for all of my vehicles from Amazon .. $25 for 5 quarts. To be honest, I haven't changed the oil in my SC since 2017. 🤔
 
But is it really high mileage, or high age? What about a 27-year-old car with 55,000 miles?

Should I use high mileage oil, even as a preventative measure?
It won't hurt anything to switch to a high mileage oil on a 27 year old 3.8L.

Rod, didn't you mention the high oil pressure being over 100psi cold?
Yep, lack of flow.

Fun fact for those with a 3.8L, this is what my 1995 owner's manual has to say about the correct viscosity for those engines.

View attachment 3089
I'd still stick to a 0W-30 or 5W-30 for the 3.8L NA.

Interesting!

I liked Valvoline synthetic after the switch from Motorcraft blend. I felt the car was quieter and smoother. I ran it for two oil changes. After that I wanted to try Super Tech to see what an inexpensive oil would do, and it doesn't seem as smooth.

I may give Pennzoil a try next. I'm curious now.


Unrelated, but Valvoline seems to be good for Maxlife ATF, too. I read lots of positive reviews.
You can pull up VOA's and UOA's for just about any oil you can think of on BITOG (Bobistheoilguy.com). You can also have your oil analyzed by Blackstone Labs or the like (I do).
 
I run Amsoil OE synthetic 0W-20 in my Silverado and wife's Honda Passport. I'll run Amsoil Signature Series in the 347 when it's built. I'll decide on weight with help from the builder. My nephew is running that in his 406 SBC with good luck so far. It's expensive, but I've been using it in other vehicles and snowmobiles since 2000 or so.
 
have heard that 10w40 will kill these quick, but IDK. I'm not going to try. :)

My Cougar has been running 10w-40 for last 3 years, I ran 5w-30 up North. From my basic understanding having the winter weight closer to the actual oil viscosity is preferable, if it is suitable for the climate. I noticed my oil pressure went up a tad according to the dash gauge with the 40 weight. Then again not sure how accurate that is since it's just a stock gauge with the mod done to it.

Engine seems perfectly happy, it has never burned oil and valve body is very quiet. I just switch to the 40 weight because of the hot climate and I take it into the ketchup fairly often :LOL:
 
Started mine at first oil change at 400 miles w/ Mobil 1 5w-20 per manual. Over the years I've used synthetic or motorcraft synthetic blend from Mobil 1, valvoline including max-life, havoline, Walmart synthetic but with motorcraft, wix or Purolator filter. Intervals have been from 3000 to 19k one time I misplaced my manual. I don't burn much as egr is always clean and iac is cleaned every 50k or so. On the other hand, since about 2000 or at 120k miles the damn oil pan weeps all around to the tune of about a qt every 3000 miles. I recently tried Lucas synthetic oil stabilizer (not the clear goo in qt bottle) that comes in a 12 oz can for about $15. It is dark brown and sort of thick. That stuff slows the weep better than anything I've tried yet. I have a melling hv oil pump ready to go but I'm not sure I need it. I'm still amazed the chain tensioners are still factory. I do have a little startup noise but it isn't bad. I am shooting for 400k before pulling the engine.
 
Multi-grade oils are measured at 2 temperatures, 40c and 100c, or around 100f and 210f. This is a good test because it pretty accurately reflects temperatures that engine oil experiences in real world usage. If you ran a straight 30 weight oil, at 210f operating temperature, it would have the exact same viscosity as a 10w30 or a 5w30, or a 0w30. Same thing with a straight 20 weight compared to a 0w20 or 5w20. So when people say that 0w20 is too thin so they run 5w20, at operating temperature, there is no difference between those 2 oils. Now when cold, a 0w20 will be thinner than a 5w20, but that’s a good thing! Engines are designed with a particular viscosity in mind at operating temperature, and even if you put 0w16 oil into an engine designed around 10w40, the cold oil is too thick! The issue with cold start is far less about film thickness, and more about getting the thick cold oil to all the critical locations, and 0w16 at 30F or even 100F is much thicker than 10w40 is at 200F. If your car is a race car that is subject to extreme abuse and very high oil temperatures, then there could be an argument for running say a 10w40 instead of a 5w40 or 0w40 since as temperature goes up above 210F, the 10w40 will be thicker than the 5w40 or 0w40, and under those extreme conditions, the added thickness may be more beneficial than the costs of it being too thick when cold. This balance is shifted even more in a race car situation since the engine (or at least the oil) will be warmed up prior to driving, and also most race car engines are not expected to hold up for 200k miles. But in the case of a regular street car, your oil will never be above 210F, and so a 0w20 will protect just as well as a 5w20, and a 5w30 will protect just as well as a 10w30. So in short, you always want the lower number to be as low as possible! If your car calls for 10w30, then 5w30 would be better. If it calls for 5w20, 0w20 would be better. Now as far as synthetic vs conventional vs blend goes, synthetic will almost always be better for your engine. Synthetic oils can achieve much more consistent viscosity across temperature ranges with less additives, which means they will hold up longer. A conventional multi grade oil will over time thicken, especially when cold, which is exactly when you want it thinner. This is the main reason why conventional oil should be changed much sooner than synthetic. I don’t tend to put much faith in blends because there is no standard for the synthetic to conventional ratio to call something a blend. So I could take a 55 gallon drum of conventional oil, pour in one quart of synthetic, stir it up, and call it a synthetic blend oil! Since there is no standard on the ratio, and that information is not readily available, I treat all blends the same as conventional oil. If you have a beater that you don’t put a lot of miles on, and you live in a temperate climate that doesn’t see freezing temperatures, and you are easy on it, then go ahead and run conventional oil, and change it once a year or every 3k miles. Also some conventional oils, specifically diesel oils have higher zinc content, so if you have an older engine with a flat tappet cam, there is an argument for running conventional oil in those engines, however for most people who care about their car, and the longevity of their engine, synthetic oil is going to be better. As for how long to go between changes, there are differences of opinion there, but I’m of the opinion that oil changes, even with synthetic oil, are the cheapest insurance compared to the cost of an engine. Personally, I run synthetic oil in all of my vehicles, (5w30 in most of them, and 0w40 in the F150s 393 stroker) and I change it every 6k miles. I really don’t like the idea of going 10k+ miles like some manufacturers are suggesting now, and I see a lot of engines with oil consumption issues and sludge buildup, and I have yet to see that happen in any engine that uses a good quality synthetic oil, a good quality oil filter, and changes the oil every 6-7k miles!
 
I totally agree, Mikey. I change oil every 2500 or 3 months. Oil is cheap, hard parts are not. One of m Uncles was a Subaru and Ford mechanic, and he told me that when I was still riding motorcycles, and hadn't started driving yet.He also helped me understand what the layers in the oil I saw when I drained it out of the dirt bike were. :) The 2 stroke IT bike turned oil back into its component parts, lol. Everything except castrol gtx. I still use castrol products when possible.
Changing it also gets rid of the fine carbon that gets past the rings. It's an awesome abrasive. Bad for bearings.
The 3 month thing: If you don't drive 2500 miles in 3 months, you're driving short trips everyday. So more water and gas accumulate in the oil.
You really need to drive a car ~15 minutes if you drive it. This gets rid of the water vapor and excess gas that goes places.
With those simple things, I've got hundreds of thousands of miles out of Lazarus. He's been driven hard everyday I've owned him. I'm going to reward him with a quick hone and crosshatch, new pistons, rods, bearings, seals, and hope for another 500k. :)
 

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