High mileage full synthetic, synthetic blend or conventional in a 263K mile car?

celicaxx

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Connecticut
I switched my 1994 Tercel to 5w40 Schaeffer after a lifetime of 10w30 WB Rotella and god only knows what the previous owners used. The first OCI noticed an increase in oil consumption but after that it dropped to basically nothing. I was using a quart occasionally in 4500 miles on Rotella and have run 7500 miles on Schaeffer with no make up.
Unfortunately I ended up scrapping this car due to rust.

Despite the sludge, or maybe because of it, I still had 170 PSI compression in all cylinders of that engine when it was scrapped.

Consumption was definitely lower with 15w40, I think over almost 2000 miles it used half a quart.
 
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445
Location
SW Missouri
Unfortunately I ended up scrapping this car due to rust.

Despite the sludge, or maybe because of it, I still had 170 PSI compression in all cylinders of that engine when it was scrapped.

Consumption was definitely lower with 15w40, I think over almost 2000 miles it used half a quart.
I guess with your location that’s more of an issue. Here in Missouri I wash my vehicles after they’re driven in the salt and usually have to worry more about wearing them out. I have a North Star hot pressure washer and man it takes the salt off. It’s a $4k pressure washer though.
 
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4,632
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Decatur AL USA
I wouldn't put a lot of faith in the 10W-40 being the primary cause of the winter drop. Even with 5W-20 I get a 15% drop in winter city mileage. Regardless of the grade everything in the powertrain is going to be a lot thicker and winter fuel blends give worse mpg.

While I doubt it really needs anything over 5W-30 in a moderate climate I also doubt 10W-40 is causing much issue unless you are doing a lot of sub-0F starts.
 

celicaxx

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Connecticut
Dang you scrapped it? I keep them till they absolutely quit then I keep putting money into them because I don’t like new stuff as far as cars go 🙂.
The car in general was a big long sad story. My father more or less scammed me into it to get out of fixing it for his girlfriend and sold it to me as reliable but rusty, of which it was not. It really actually messed my life situation up, as I sold my other Jetta that was apart but solid for this car, as I couldn't keep too many cars on our property with our HOA, and I trusted him that it would be reliable and initially problems were bad gas, etc.

Junkyards around here had almost no other B13 Sentras to take parts out of cheaply, it would have just been way more expensive to keep running. The catalyst to scrap it was my back window thermal cracking after getting my Fusion, it cost $300 for a new window, none in junkyards around easily. 3/4 shock towers had rust holes, trunk was rusted, rear deck was rusted, so I think the back window cracked from the chassis flexing way too much.

I love old JDM cars (see username) but my Fusion I paid $900 for is an immensely better car. It has some stuff to attend to soon (timing chain... :() but with the Sentra even getting things like rubber weatherstripping was hard. My Fusion I could buy them for $5-10 each at the junkyard, my Sentra, there were none in junkyards near me, and from Thailand new ones cost $300-400. Sentra had AC deleted by my father as well cutting the lines off at the firewall, so that would have been another $200-300 plus taking the dash apart to get AC, etc. Big thing for me too is the Fusion is a somewhat rare manual one, and my Sentra was auto. Fusion has hot heat, ice cold AC, relatively comfortable, etc. There's only one rust spot on the whole vehicle, too.

It definitely pained me to scrap it, and I didn't even intend to scrap it, but on my ad a scrapper showed up with money first without telling me he was one, so oh well. Time has to march on, hope one day I can find a Cressida or something as a nice boxy Japanese sedan. But yeah, with this car, it was an awful lesson in sunk cost fallacy and not letting bad decisions keep compounding.

I did learn to paint cars with this car, though. I did a DIY rattlecan job that turned out super well. It sucked to scrap it with my paint job, too, but I couldn't keep letting it steal my money and time away from me.
 

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Messages
7,104
Location
Roanoke Virginia
The car in general was a big long sad story. My father more or less scammed me into it to get out of fixing it for his girlfriend and sold it to me as reliable but rusty, of which it was not. It really actually messed my life situation up, as I sold my other Jetta that was apart but solid for this car, as I couldn't keep too many cars on our property with our HOA, and I trusted him that it would be reliable and initially problems were bad gas, etc.

Junkyards around here had almost no other B13 Sentras to take parts out of cheaply, it would have just been way more expensive to keep running. The catalyst to scrap it was my back window thermal cracking after getting my Fusion, it cost $300 for a new window, none in junkyards around easily. 3/4 shock towers had rust holes, trunk was rusted, rear deck was rusted, so I think the back window cracked from the chassis flexing way too much.

I love old JDM cars (see username) but my Fusion I paid $900 for is an immensely better car. It has some stuff to attend to soon (timing chain... :() but with the Sentra even getting things like rubber weatherstripping was hard. My Fusion I could buy them for $5-10 each at the junkyard, my Sentra, there were none in junkyards near me, and from Thailand new ones cost $300-400. Sentra had AC deleted by my father as well cutting the lines off at the firewall, so that would have been another $200-300 plus taking the dash apart to get AC, etc. Big thing for me too is the Fusion is a somewhat rare manual one, and my Sentra was auto. Fusion has hot heat, ice cold AC, relatively comfortable, etc. There's only one rust spot on the whole vehicle, too.

It definitely pained me to scrap it, and I didn't even intend to scrap it, but on my ad a scrapper showed up with money first without telling me he was one, so oh well. Time has to march on, hope one day I can find a Cressida or something as a nice boxy Japanese sedan. But yeah, with this car, it was an awful lesson in sunk cost fallacy and not letting bad decisions keep compounding.

I did learn to paint cars with this car, though. I did a DIY rattlecan job that turned out super well. It sucked to scrap it with my paint job, too, but I couldn't keep letting it steal my money and time away from me.
Oh yeah I have never seen one of those in a junkyard around here either. They are few and far between nowadays. ☹️. I’ve never really painted a car before lol not even rattle can. Cressida are nice too you hardly ever see those anymore either unfortunately.
 

celicaxx

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Connecticut
Well she does need a paint job. Still haven’t decided on a color yet. View attachment 48010

This is the guy I learned from and that was roughly my process. Only difference was I tended to paint 3-4 light passes of top coat, whereas he paints heavier, but I also did the car panel by panel, as it was easier to budget time that way. Because you could drop cloth off the other panels and just mask 1-2 windows, etc, whereas masking a whole car can take a while.

In your case, I'd start with the rust back engine cover piece (I don't know what to call it on Beetles...) and sand as much rust away as possible, then use Rustoleum Rusty Metal primer on it all, then top coat 2 in 1 filler primer, wet sand that down with 300-500 grit, then top coat with whatever color Rustoleum you want. You could experiment with a few different colors on just that engine cover and see what you end up liking. Kinda similar to buying a sample quart and putting it on the wall in your house.

If you have a real paint gun and compressor, you have a lot more options available, probably the best would be Speedokote's (BASF) clear coat, of which you could use Rustoleum satin rattlecans as a basecoat, or buy their fleet or black 2K single stage. 2K is definitely more durable and overall a better job, but the rattlecans are definitely serviceable paint jobs. Disadvantage of a gun is it's not practical to do small parts a little at a time, as you have your gun cleanup/etc to do, and if you use 2K paints the paints are activated and will go bad in a day after you add catalyst. You can use normal Rustoleum oil based paint in a gun and it can look great as well, and it's marginally cheaper than rattlecans. If you go Rusto it might ironically look more period correct than a 2K urethane paint job, as 2K urethane didn't exist back then, and you can still get incredible shine if you wetsand and buff.

The only thing I'd say NOT to do which I also tried was rolling Rustoleum with foam rollers. That was an outright disaster, but the rattlecans turn out great.

Keep in mind, I'm a house painter by trade but rarely spray and I had no automotive experience, but yeah.
 
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Messages
7,104
Location
Roanoke Virginia

This is the guy I learned from and that was roughly my process. Only difference was I tended to paint 3-4 light passes of top coat, whereas he paints heavier, but I also did the car panel by panel, as it was easier to budget time that way. Because you could drop cloth off the other panels and just mask 1-2 windows, etc, whereas masking a whole car can take a while.

In your case, I'd start with the rust back engine cover piece (I don't know what to call it on Beetles...) and sand as much rust away as possible, then use Rustoleum Rusty Metal primer on it all, then top coat 2 in 1 filler primer, wet sand that down with 300-500 grit, then top coat with whatever color Rustoleum you want. You could experiment with a few different colors on just that engine cover and see what you end up liking. Kinda similar to buying a sample quart and putting it on the wall in your house.

If you have a real paint gun and compressor, you have a lot more options available, probably the best would be Speedokote's (BASF) clear coat, of which you could use Rustoleum satin rattlecans as a basecoat, or buy their fleet or black 2K single stage. 2K is definitely more durable and overall a better job, but the rattlecans are definitely serviceable paint jobs. Disadvantage of a gun is it's not practical to do small parts a little at a time, as you have your gun cleanup/etc to do, and if you use 2K paints the paints are activated and will go bad in a day after you add catalyst. You can use normal Rustoleum oil based paint in a gun and it can look great as well, and it's marginally cheaper than rattlecans. If you go Rusto it might ironically look more period correct than a 2K urethane paint job, as 2K urethane didn't exist back then, and you can still get incredible shine if you wetsand and buff.

The only thing I'd say NOT to do which I also tried was rolling Rustoleum with foam rollers. That was an outright disaster, but the rattlecans turn out great.

Keep in mind, I'm a house painter by trade but rarely spray and I had no automotive experience, but yeah.
That’s actually pretty impressive and yes I have a compressor and gun at home. My dad painted a car before I was born and quickly determined it wasn’t for him so he didn’t do anymore after that lol. I have a feeling my rattle can job would have too much drip to it though.
 

celicaxx

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159
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Connecticut
That’s actually pretty impressive and yes I have a compressor and gun at home. My dad painted a car before I was born and quickly determined it wasn’t for him so he didn’t do anymore after that lol. I have a feeling my rattle can job would have too much drip to it though.
Welp, the good thing is you can sand it out and redo it as many times as you'd like. :p For me with the rattlecans I found just spraying 8" or so away and moving quickly minimized any runs, and going a light tack coat, wait 3 or so minutes, then apply your second and third or fourth passes light also, until you get it fully covered.

My Sentra honestly took me 3 times to get it like the photos. Practice on one panel, and if you get that panel good, go on to the next.
 
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21
Location
Aitkin,MN,USA
I'd just run the cheapest quality dino or HM that I could find and call it a day. At 263K, whatever got it there must have had some level of success.
I agree. ..except you are killing your ..FLEET..using W40!! Only run the cheapest oil you can get that matches your owners manual. I am running FVP 5W-30 at <$3/qt, 6000Mile OCI ..WIX or Purolator 1 filter. No leaks, 3000miles to the qt. Try evolving to cheap high mileage oil and watch carefully for leaks.
 
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21
Location
Aitkin,MN,USA
Originally Posted by Triple_Se7en
Just stay with what's working for the aged vehicle. Don't even change brands. Use 10w30 conventional in winter and 10w40 in the spring, summer and fall.
Yep, use 10w30 year round smile
No..not 10w30..go 5w30..faster circulation at startup. I quit major brands..wont use ST because it is Walmart . Any cheap certified oil is good. Me and my old 3.5L V6..love FVP..185,000miles and miles per quart is still going down..was 2000/qt...now 3000+ /qt.
The sudden increase in fuel consumption may have been caused by supplier switch to winter-blend fuel. I've been a fan of high mileage oils which have higher HTHS and/or concentrations of antiwear additives such as moly. No empirical data to show they are more effective than non-HM oils, just observing quieter valvetrains on my vehicles vs. Mobil-1 non-HM in all 3 cases. Pennzoil Platinum HM 5W-30 has been my go-to for quietness on my '07 4Runner. Valvoline MaxLife synth blend 5W-20 is a more recent addition here, using it in my wife's '05 Mercury Mariner and near-zero oil loss on the dipstick at 1.8K miles (too soon to tell if this is an improvement over previous PPHM 5W-20). So...I'd go with HM oil. Pennzoil High Mileage has been a good conventional option for me and a neighbor I help, it's cheap. PPHM if you want to pop for synthetic, however for your specific vehicle I'm not certain you'd see any incremental value versus the conventional version.
?? Mileage dropped because you put thick oil in. Why W40..I bet your owners manual says W30 or W20
Hi, right now in my 1994 Sentra I'm running Supertech 10w40. I had no real particular reason why I ran it, the car was pretty much on its last legs when I got it and it's been brought back to life somewhat now, to the point it's an around town kind of vehicle. I basically only ran the 10W40 as I had another car a couple of years before with a severe front main seal leak, and I bought it as a 5 quart jug to limp it around before I sold it, and I had 3 quarts left in the jug and the car came with a quart of Formula Shell 10W40, and it's a 3.5 quart car. I put it in, probably in... August or September? It seemed to run smooth then, but I noticed kind of randomly a giant gas mileage drop, from about 23-25 city, to 20-21 city, with cold temperatures finally hitting harder. However, this week it was relatively warm, and I got 25mpg again. So I'm thinking it's a case where the 10w40 doesn't heat up sufficiently in winter, especially with a lot of short trip driving. Also the engine has sludge too, and my oil is pretty much black after these 1500 miles, so I'm hoping to change it out for that reason as well, at least the detergents are working. As it is now, I'm really happy about its oil usage, even with a slight valve cover leak it's only used about 1/4 of a quart in about 1500 miles. This is with non high mileage conventional Supertech 10w40. However, the seals aren't really good at all on it, the spark plug seals were rock solid, along with the valve cover gasket, they just broke into solid pieces by bending them with my fingers when I changed them. So I'm hesitant to try synthetic, though I've had other people tell me they had decent results switching to synthetic on old cars like this (my friend told me he had a sludged up Civic where chunks of sludge came out of the oil pan, and he did 5-6 3K OCIs with synthetic and it cleaned a lot of sludge out...) but I'm pretty scared. At Wal-Mart right now, ST conventional and synthetic are within a dollar of each other. I've also read some conventionals are just secretly synthetic now as well. I think now with more fracking, synthetics are dropping in price due to more natural gas being found? I know even some bulk oil in drums for oil change places are synthetic blends now, as well (place where I briefly worked had 5W30 syn blend bulk oil....) I had a Volkswagen prior to this, and in that with similar mileage (but a lot better shape, except for a cooling system problem and being hard to work on in general...) I alternated between 15w40 Mobil Delvac and 5W40 Rotella. I actually ironically got about 1-2mpg more with 15w40 compared to the relatively fresh 5w30 in it (friend gave me the car, pretty OCD about oil changes and related stuff...) in summer in the Volkswagen, maybe some gains in compression? In winter the 5W40 Rotella seemed to run fine as well, no mileage drop, so that's partially why I felt OK running the 10w40 in the Sentra, figuring the heavy oil thing in cold weather was a myth/overstated. My father personally got 450K out of a Ford Freestar without going into the engine, and driving it to the junkyard with Rotella 15w40 and 3-4K OCIs (in an engine spec'd for 5W20.) With the diesel oils my Volkswagen ran super nice and smooth, so I was thinking of running a 5W40 diesel oil again, but I don't know if it would cause a mileage drop in the Sentra still compared to 5W30 (it says 5W30 preferred under the hood on the sticker, but makes allowances for up to 20w50 in summer...) but most of the 5W40 diesel oils are synthetics or synthetic blends. So, what should I run? Full synthetic 5W30 high mileage, 5w30 conventional, (high mileage or normal?) or a 5W40 diesel oil? Thanks very much!
Doesn't your owners manual say W30? If so I would never run W40..too thick! Desert country or cooler.... I assume your cooling system is maintaining about 200F
 

celicaxx

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159
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Connecticut
No..not 10w30..go 5w30..faster circulation at startup. I quit major brands..wont use ST because it is Walmart . Any cheap certified oil is good. Me and my old 3.5L V6..love FVP..185,000miles and miles per quart is still going down..was 2000/qt...now 3000+ /qt.
?? Mileage dropped because you put thick oil in. Why W40..I bet your owners manual says W30 or W20
Doesn't your owners manual say W30? If so I would never run W40..too thick! Desert country or cooler.... I assume your cooling system is maintaining about 200F
It had a graph, said "5w30 preferred" but allowed up to 20W50 depending on temperature.

I ended up trying 10w40, 5w30, and 15w40 in my short ownership of it, and it didn't seem to make any mileage difference at all. I think maybe my Chinese o2 sensor was the cause.
 
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336
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NJ
?? Mileage dropped because you put thick oil in. Why W40..I bet your owners manual says W30 or W20
Doesn't your owners manual say W30? If so I would never run W40..too thick! Desert country or cooler.... I assume your cooling system is maintaining about 200F
Where did you get this? Nowhere in my post did I state that I used a "W40" oil, or anything thicker than whatever was specified.
 
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