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A question about the Rotella Motor Oil

3512 Views 19 Replies 10 Participants Last post by  N0DIH
I read on this fourm like 5 month ago that the Rotella was a good oil to put in the 4.1 engine cause it help the lubricate certain part in the engine but recently I did a oil change and added lucas oil stabiler and my oil turn real dark very fast I was wonder do anybody got any suggestion why it turned that dark after a week. And what causes black smoke to come out the muffler.
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don't use the oil stabilizer....

Lucas makes good stuff, but that stuff is known to foam up, and really any oil additive just changes the additive package in the oil (whatever kind you may be using) and todays oils do not need anything extra...

I would get that stuff outta there as soon as I could though.
Caddy_2004 said:
I read on this fourm like 5 months ago that the Rotella was a good oil to put in the 4.1 engine because it helped to lubricate certain parts in the engine. But recently I did an oil change and added Lucas oil stabiler and my oil turned real dark very fast. I was wondering if anyone has any suggestions why it turned that dark after a week? And what causes black smoke to come out the muffler?
:D
If your engine oil is turning dark that quickly, then your engine may be very dirty and therefore may need some good ol' Gunk engine cleaner ran through the engine on the next oil change. However, judging by your black smoke from the exhaust, there may be a carbon intrusion that is also getting into the oil causing a rapid darkening of the oil. The Lucas oil stabilizer didn't do that...

For the Rotella, use the 15w40 if you would so like to, I have heard nothing but good things about it.
*IF* the engine is infact that bad where it turns the oil dirty fast (as in the case of my 425... and my 3800 to a lesser degree) then I would NOT use the engine cleaner... the detergints in there would start to break stuff up, and that is just asking for clogged oil passages, filters and a host of other problems.

I say switch to the Rotella 15W-40 and change the oil every 3,000 miles in your case, don't add anything to the oil, and if the engine is in fact dirty inside, leave it be, JMO :).
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I find that the best way to clean a dirty engine is to use shorter oil change intervals and run it hard (get that oil hot) for a while. For example, you could change that dirty oil out in maybe 500 miles, then give it another on 1,500 miles after that. Don't really even have to change the filter ever time. Of course, change it at the normal interval, but in the next few frequent changes, just use the same filter. Use any interval you like, and gradually bring yourself back up to your normal oil change interval. The natural detergents in any brand or type oil will clean that motor out over time. If you take the tip on the filter to save some money, don't forget about it when it actually comes time to change it!
I use the Rotella in my 4.9 and my 4.1, I was wondering if it was ok to use in a 3.8 as well. I've heard that it should be fine I know of a few people that have used it. I just wanna make sure that 15w-40 is ok for that engine as well.
Regarding changing the oil often to clean it out, that is a very good idea.

I had a similar problem on my 85 Deville where I noticed that the oil on the dipstick got dirty quickly and felt kinda grimy. Turns out the PCV filter was completely plugged. I replaced the PCV filter immediately. Took two or three oil changes for the oil on the dipstick to return to normal. After that, everything was fine.
yes, the best way to clean the engine is as mentioned.

In the case of my 425 though, it is beyond frequent oil changes... when the valve covers were removed everything was baked on so much it was nasty.... even in the valley when the intake manifold was off... quite dirty inside.

3.8.... you mean the 3800 used in FWD? or 3.8 used in RWD?

Either way, my '89 3800 requires 5W-30... designed for lighter oil, so I don't think the 15W-40 Rotella would be a good idea.... plus that engine is more oil friendly, has coil pack, so no distrubutor gear etc.... I'd just use your favorite brand of 5W-30... for me, it was Mobil :).
Night Wolf said:
*IF* the engine is infact that bad where it turns the oil dirty fast (as in the case of my 425... and my 3800 to a lesser degree) then I would NOT use the engine cleaner... the detergints in there would start to break stuff up, and that is just asking for clogged oil passages, filters and a host of other problems.
I say switch to the Rotella 15W-40 and change the oil every 3,000 miles in your case, don't add anything to the oil, and if the engine is in fact dirty inside, leave it be, JMO :).
Okay...:bigroll:
illumina said:
Okay...:bigroll:
Did I say something wrong?
Night Wolf said:
Did I say something wrong?
I just don't entirely agree with you, that's all. Sorry if I typed the smart-assed remark instead of giving a better argument...Here goes:

I will agree that Lucas isn't the answer for an engine, but I recall reading the "Bob's the oil guy" article about it, and the test subject was a gear case that caused the Lucas to froth up when combined. Should the Lucas be put into an engine, it will not even come close to frothing like that because of the lack of gears inside an actual car engine. That doesn't mean that it doesn't froth up, but not like the article suggested. The closest exception to the rule will be the distributor gears on the cam and the distributor, but still, that should not cause frothing like the article suggested...

As for the Gunk engine cleaner, I use that stuff at least once a year to make sure there is no gunky build-up. Notice the term "build-up." Build up occurs where engine oil will be able to stand for a long time. I agree that oil passages can be blocked off, but when used properly, the Gunk will break the standing oil residue into small enough bits, and along with the engine heat, that should be enough to remove the vast majority of the build up. In all honesty though, if the engine is that dirty, the Gunk will not help at all, unless several oil changes are done in a row (like 5 in the same day), as well as using the Gunk each time. So that's a mistake on my behalf.

Now, as I stated before, his oil turned black for many reasons. And when his exhaust turns sooty black like he stated, there might be excessive carbon build-up. When the oil is turning black instantaniously, there might be a carbon intrusion in the valve guide areas or because of older piston rings. With the valve guide issue, I think carbon deposits will intrude and get into the oil track where it will then help to cause the oil to turn black. For the pisiton rings, there might be a mass build-up of carbon on the pistons and some of that is being forced into the crankcase or something like that. Either way, black smoke sounds like carbon to me, and when you combine oil that was darkened very quickly along with the black smoke, that tells me that there is carbon getting into the oil somehow.

All that said, I still use Lucas (I know it's snake oil) and have had zero (0) problems with it frothing up like that. I do notice an occasional bubble from time to time, but not like the aforementioned article. And one thing too, it has yet to turn my oil black right after an oil change. Even after 3 or 4 months, the oil is only dark brown.

:cool:
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I agree with you on most all things you have said.

back in the winter of '03/'04 I used a quart of Lucas Oil Stablizer in my Oldsmobile.... it didn't seem to change much for better or worse.... since I used 10W-30, right after startup the lifters would tap for a few seconds... the Lucas stopped that... then again on the other oil changes I used 5W-30 (what it says on the oil cap) and there was no lifter tap either.

Lucas fuel injector cleaner is pretty good.

I missed the part about the black smoke from the tail pipe... in that case, yeah, black smoke is usually carbon burning off... or too rich.
I'm wondering if I should use Rotella 15W-40 in my '93 Fleetwood Brougham due to the 350 cu-in engine having a dsitributor, etc. but the owner's manual states "do not use 10W-40 oils". Using 15W-40 concerns me since it is heavier than 10W-40.
KHE said:
I'm wondering if I should use Rotella 15W-40 in my '93 Fleetwood Brougham due to the 350 cu-in engine having a dsitributor, etc. but the owner's manual states "do not use 10W-40 oils". Using 15W-40 concerns me since it is heavier than 10W-40.
15W-40 is only more heavy then 10W-40 when it is cold, once warmed up, they are the same.

Ya know... I dunno what to say, I would say use 10W-30, thats what I would use if that was my car, but others have different opinions. The Rotella 15W-40 I have heard from a reputable source is very good for the 4.9 though.

I personally use Mobil 1 Extended Performance 10W-30 in the '93 4.9, Mobil clean 5,000 10W-30 in the '79 425 and Mobil clean 5,000 5W-30 in the '89 3800, I have not had any oil issues yet.
I have been using Rotella near Chicago area since it warmed up early this year. Well, it will be cold soon (it is pretty cold already...) and I am wondering if keeping this thick oil in it is going to be a trouble when I start the engine in the morning.

What do you all think? Does anybody who lives up north where temperature drops around 0 F use 15W-40 in winter and experience no problem?

Thank you.
Forgot to say... Rotella has been very good with me. I don't hear that bearing noise when start-up and the engine does not loose oil as quickly as it did before (1 qt/1000-1500 miles -> virtually none).
I am running Rotella T 5W40 now, seems fine (no fuel economy savings over 15W40, I have tons of miles documented and nothing....)

But the synthetic oil seems to have "cleaned" out some oil seals that are now leaking some (rear seal or oil pan, not sure which yet).

15W40 is still in my Subruban with the Vortec 350. In 30 degree weather, it starts up fine, no issues.

10W40 has more additives vs 15W40, and was causing GM ring sticking problems. so GM banned its use (and voids warranties). I am actually surprised it is still even sold.
100 said:
I have been using Rotella near Chicago area since it warmed up early this year. Well, it will be cold soon (it is pretty cold already...) and I am wondering if keeping this thick oil in it is going to be a trouble when I start the engine in the morning.
What do you all think? Does anybody who lives up north where temperature drops around 0 F use 15W-40 in winter and experience no problem?
Thank you.
There was no problem starting the car in very cold Pennsylvanian mornings last January (below 0). Rotella 15W-40 year around!
Thank you all.

So, no one had any starting issue in winter with Rotella 15W-40. Well, I am glad, but at the same time, I am wondering, then what is the point to use 5W-30...

Maybe 15W-40 is fine year around for 4.9 (well mainteined one) as long as you live south of Canada.
I have 15W40 Rotella T in my 1996 Vortec 350 Suburban. So far, with the temps we have seen tis year, absolutely no issues. I am running 5W40 Rotella T in my 94 Fleetwood and no issues either. I'll probably switch back to 15W40, as I see absolutely no fuel economy differences from 5W40 Rotella T to 15W40 Rotella T. (I am doing several fuel economy experiements, and keeping detailed accurate data on them, and this is one that has no benefit in warmer months)
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