Thicker oil to reduce consumption

[CJH]

I have a car that uses some oil...varies with temperature from about 1 qt/700 miles at 0 degrees F to about 1 quart/3,000 miles at 85 degrees F.

The car calls for 5W30, but I have experimented with various oil grades ranging from 5W40, 5W50, 10W40 and most recently 20W50 (no - didnt try 15W40 or 15W50). I have not noticed any significant reduction in drivability, starting or fuel economy with the 20W50, but I wouldn't doubt some could be measured using accurate measuring devices...still...not enough to worry about.

Since varying temperatures seem to cloud the consumption rate, I am wondering if any others have experience using thicker oil to reduce consumption.

Please don't explain to me that thicker oil doesn't fix worn engines and that I should have the engine rebuilt. The car is only worth $1,500 or so, it starts and runs perfectly and there is no smoke...so I am not anxious to spend money on engine work that may or may not correct the problem. I am just making a hobby out of experimenting with my rolling oil laboratory.

What I would like to know are others' experiences with using thicker oil to reduce consumption. Does it work and are there any adverse side effects?

 

[ediamiam]

I consume w/ 5w30 on my Mazda 6 cyl, but it seems to stabilize w/ 10w30, heavier stuff makes it seem sluggish. Perhaps you should try one those himileage type oils. Somebody will probably tell you to replace your pcv.

 

[GROUCHO MARX]

Maybe you have some crud around a few valve seals. The thicker oil or even STP might help the consumption, but if you're experimenting maybe you could RX it. You might be surprised.

 

[CJH]

Thanks for the replies. The 5W30, 10W40 and 20W50 oils I have used / am using are high mileage oils.

I have given the car 2 Rx treatments with no improvement.

I would like to hear other' experiences with using thicker oil to reduce consumption and whether any adverse side effects were experienced.

Thanks

 

[tuong]

hello cjh. I came to this website lookinf for the answer to the exact same problem you are having. . From day one my car burns oil. but after a lot of experiments and research, i found it to be pointless to find a solution because my car was built to burn oil when I drive it hard.(02 honda prelude 90k)
i have experiment with various oil and even bought the book that recommend me to this site, (how to select a motor oil...) i notice that 5w30 synthetic is smoother on my engine compare to the heavier wieghts 40's 20's. I tried 10-40 15-20 15-40. the oil does consume less with the 40 wieght, but not by much. and my engine doesnt like it. ( u ask me how i know, its cause my car and i are like one, she tells me things, no just kidding, i can just feel how my engine runs on different gas or additives)
I notice though that conventional oil burns A LOT less than synthetic. but i refuse to put conventional oil in my car because i like to spoil her.
hope that helps.
tuong

 

[jorton]

92 sentra 189,000 miles
This car has a bad rear main seal. Leaks 1/2 quart every 2 - 3 tanks of gas.

I am trying a 60/40 mix of 10w-40 and sae 30. It's only been in for 1 tank full but the oil's still full.

Cold startups don't sound too good so I may dump it.

 

[CJH]

Thanks guys,

The 20W50 SEEMS to be helping somewhat, but I am not sure how much at this point. It has not cut it in half or anything like that...I am keeping track of it and time will tell. I thought I would notice a big difference from the 5W30 in some way...engine noise, hard starting, feeling less power, or more fuel consumption...but it is not really noticably different. I dont think the grade is nearly as critical as many on here seem to think.

Oil use in certain Honda Prelude engines is very well documented on Honda discussion groups.

 

[MIAMI-DADE]

I hope for the most part most people won't even think of using such a oil in todays engines.My friend blew his engine running 20w50 in his '98 Town car with the 4.6.Until then it was fine with close to 200k.I amost blew the engine in my '88 Crown vick using it a few years ago.If i put 20w50 in my '99 Vick i wouldn't be able to sleep at night at all.

But it might work well for your Honda Prelude.

 

[CJH]

The car I have the 20W50 in is a 1997 Chevrolet Lumina with the 3.1 engine - has 135,000 miles on it. Like I said, you can't notice any difference from 5W30. So far, I am sleeeping fine. Are you sure the Town Car problems were oil-related?

I wonder how straight 30W would perform?

quote:

---

Originally posted by MIAMI-DADE:

I hope for the most part most people won't even think of using such a oil in todays engines.My friend blew his engine running 20w50 in his '98 Town car with the 4.6.Until then it was fine with close to 200k.I amost blew the engine in my '88 Crown vick using it a few years ago.If i put 20w50 in my '99 Vick i wouldn't be able to sleep at night at all.

But it might work well for your Honda Prelude.

---

 

[dickwells]

Note: 4.6 engines must have 5wx or lower oil in order for the timing chain tensioners to get oil pressure fast. If the chains are allowed to slap around for more than a second, you are on borrowed time.

 

[widman]

In our part of the world the normal oil used (40%) of the market is SAE 40, even though mornings are from -15 C to +15 C. So there is a lot of consumption and early wear. We also end up with many of the worn-out Japanese cars that are then converted to left hand drive and used as taxis or private cars. They are sent here when they no longer pass the exhaust inspections in japan
AS a RULE, we move almost all of these to 20W-50.
In heavy trucks (mostly Volvo) we move people to 20W-50 when they start consuming on 15W-40 or when they have used SAE 40 for a while. We always end up reducing consumption.
About 4 years ago I got a 97 Mazda pickup in payment from a customer. It had 125,000 km on it (with Amalia 15W-40, since most of it's life had been with an Amalie distribuitor)and consumed 1 liter every 5000 km. I moved it to 20W-50 and reduced the consumption to 1/2 liter in 6000 km (oil change point). Consumption is now back up to about 1 liter every 4500 km, and I will soon rebuild it, but it now has 280,000 km on it. Then it will go back.
A friend bouthg a Ford Explorer a few years back and drove it home from the dealer with the original 5W-30 in it. After the 750 km drive home he took it to the local Ford rep, who put straight 40 wt in it. (Morning Temps -5C to +10C). I made a lot of noise for 2000 km and then they changed the oil again with the 40 wt. after 2000 km more of noises, he came to me and we put 5W-30 in it and it got super quiet. After 3 changes in a row at 5000 km when it was down a liter, we raised it to 15W-40. He has now gone about 3 years with 15W-40 and consumption less than 1 lt every 6000 km oil change. (yep, if it was the US he could sue the Ford shop for putting in the 40 wt)

 

[MIAMI-DADE]

Yes **** Wells you are right.The 4.6 needs the 5w for the timing chain tensioners.The dealer said the tolerences are so small for the oil to get though they Must have a 5w.They recomend 5w20or 5w30 ONLY.I'm using 5w20 semisyn oil now in Miami heat.Seems ok.Sometimes i use 5w30.The car has 102k and that all it had since new.

The '98 Town Car was checked out after it died and no problems were found.They said the engine starved to death.The car was always dealer sevieced.
Thats the report the dealer came up with after checking it out.

Widman,the dealer rep. was a total idiot and should not be working for ford.I think you'll agree on that.

I never heard of anyone in their right mind using a straight anything in cars since the 60's.

 

[Drew99GT]

CJH, I remember you on here back in the day! Didn't you have good luck with Rotella 5w-40?

I'm in the same boat as you. I have an oil drinking 94 Corolla; car runs good/decent power but it consumes oil. No smoke either. I've done 2 RX treatemnts and now have been using Lube Control. LC has really reduced the consumption a lot, but it's still around 1 quart every 1500 miles or so highway driving. I'm looking at going 50/50 20w-50 and 10w-30 to see how that does.

 

[1sttruck]

If you get blue smoke at start up in the morning I'll guess that it's valve seals, otherwise it's probably oil control rings if you're using oil. Our older Honda had lots of blue smoke before we donated it, while our Taurus starts up fine but sipped quite a bit otherwise. I used some Mobil 10w30 5000 at the last change and it really started using oil, I usually add a couple of qts of 5W40 T&S but didin't, so I topped off with a qt of Rislone instead of more oil (engine treatment, not the ring stuff). When the full qt was in the oil consumption slowed waaay down, where I used a cup in the interval that I would normally use up to 2 qts.

I'll drain it here shortly and do another couple of 1k to 1.5k oil changes with Rislone, something that a BMW mechanic suggested on one site. If you've already done AutoRX and LC Rislone probably won't help much, but at $3 to $4 a qt, one qt per oil change, it's easy to try it out. A number of people report adding it at every oil change for long periods with no problems, so it seems safe to use.

I'll switch to 100% 5W40 T&S, or maybe Motorcraft 10W30 HDEO (available at Ford). I've given up on PCMOs as they've traded off cleaning and anti-wear for mileage and emissions.

 

[darkdan]

quote:

---

Originally posted by dickwells:
Note: 4.6 engines must have 5wx or lower oil in order for the timing chain tensioners to get oil pressure fast. If the chains are allowed to slap around for more than a second, you are on borrowed time.

---

Gonna have to throw the BS flag on that one.

Start-up viscosity has a lot more to do with ambient air temps then what oil you're using.

A 20w50 in june is a lot thinner than 0w30 in MN winter.

So, "appropriate cold viscosity" is much better term than "needs 5w".

 

[JohnBrowning]

20W50 works good to stop consuption but 15W40 willusualy do just as well in most cases. 15W40 has a better additive package then most 20W50's! Delvac 1300,Delo 400 would be my first choices. You might also try Delo 400 in SAE 30Wt. not 10W30 just 30Wt. AutoZone sell's it and it might help just as much aas a 20W50. Give it try?

 

[MIAMI-DADE]

Darkdan what would you recomend in a '99 4.6 with 102k.

Right now the dealer in putting in 5w20 semisyn motorcraft.But if i don't go to the dealer i have the oil change place put in 5w30 semisyn
casrtol.Seems ok but what is your take?

Mind you traffic is nightmare here all the
time and a/c is never off

I don't want to go to full syn as it never had it and only started using semisyn at 90k.Thanks in advance.

 

[Jimbo]

1980 Toyota Supra started smoking badly at about 175,000 miles on the then-recommended 10W-30. Straight SAE 40, no smoke. For those here that are horrified at the lack of startup lubrication and all that, the engine continued to produce good power and even pass emissions tests until the car was scrapped for too expensive to fix electrical problems years later.

 

[MIAMI-DADE]

Straight 40 may have worked for your '80 Supra but i hope nobody gets the idea to put that stuff in newer vehicle.

Thats scary even to think about that.HORRIFIED dosen't even come close.

The boneyeard is full engines that used 20w50 that should have not have.

 

[wileyE]

No arguement or debate here, just wondering where the failure occurs? A large construction company that does work for us has a whole fleet of 4.6 f150's being serviced with bulk 15/40 "equiptment oil", have been for quite some time now. Any idea what to watch out for?