Going From Synthetic Blend To Regular Oil?

maczilla23

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Hello, I have been using a mercurys synthetic blend in my 4.3L Mercruiser the last 2 seasons. That is is not readily available around me anymore and I was wondering if I could switch to quicksilver regular blend or if that would not be wise? Otherwise I have to order all of my oil. Advice would be appreciated!
 

gm280

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I personally don't see any issues, but then I never used synthetic oils before either. But unless somebody can provide a very good explanation as to why not, I can't see any issues myself... IDK :noidea:
 

alldodge

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Hello, I have been using a mercurys synthetic blend in my 4.3L Mercruiser the last 2 seasons. That is is not readily available around me anymore and I was wondering if I could switch to quicksilver regular blend or if that would not be wise? Otherwise I have to order all of my oil. Advice would be appreciated!

While synthetic oils are said to protect and engine better then petroleum oils, there has not been an engine fail do to the oil being used, only by the lack of maintenance
 

Bondo

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While synthetic oils are said to protect and engine better then petroleum oils, there has not been an engine fail do to the oil being used, only by the lack of maintenance

Ayuh,.... I've decided to quit wastin' money on Mobil 1, 15W-50 for my barge, 'n switched to the diesel oil we use in the dumptrucks, 'n equipment,...
Rotella 15W-40, right outa the 55gal. drum,....

I Do still use Mobil 1, 75W-90 in All the drives under my care,....
 

Silvertip

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Here are a few details involving synthetic and regular oils.
1) Going from synthetic to regular oil has no effect whatsoever. In fact, if the engine burned a small amount of oil it may not burn as much regular oil
2) Going from regular to synthetic oil is also of no concern except for:
a) If the engine consumed (burned) some regular oil, it may burn a bit more synthetic
b) If the engine leaded a bit of regular oil, it may leak a bit more synthetic
c) If the engine became highly varnished on regular oil it may be cleaned up using synthetic. This is not likely an issue with newer engines that have seen much better quality oils than engines did in the 70's and earlier so varnish is not an issue.

In a nutshell, there are no "lubrication" issues going either way.
 

bruceb58

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I just use 15w-50 Mobil 1. I can pick it up at Walmart in 5 qt containers for around $24 or so.
 

Tail_Gunner

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I just use 15w-50 Mobil 1. I can pick it up at Walmart in 5 qt containers for around $24 or so.


Exactly how much cheaper can oil get and at the same time Mobil is at the top of the heap. And so is Rotella 15W-40 for flat tappet cam's.

Now the real question is Wix or not to Wix....
 
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bruceb58

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I Do still use Mobil 1, 75W-90 in All the drives under my care,....
DonS talked me out of using the Mobil 1 gear oil anymore. At least the stuff I find near me mentions limited slip and he was very wary of it. Maybe you can find the type that doesn't mention it on the label.
 

Lou C

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That may be an issue in a cone clutch drive but may not matter in a dog clutch drive like an Alpha or Cobra...
 

HT32BSX115

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HT32BSX115 commented on this topic once perhap's he is right wrong..who know's...............:fish2:...I guess we will find out shortly...:biggrin1:

Ok,

I can't stand it! I guess I do have to comment on this again.


I have searched all over on the place looking for info on using oil with limited slip additives in any cone-clutch drive like a Bravo or a VP drive. A lot of people say "don't do it" but they don't say why (well they say "why" but not "why" why.


I have not really been able to find any definitive information on why limited slip additives would cause any problems in a stern drive because they're designed to work with the clutch plates and clutch material in a rear axle or a cone clutch in a rear axle that has similar clutch material on the tapered "male" surface that are designed specifically to "slip"

A stern drive clone clutch uses no clutch plates or clutch "material" . They're tapered, dissimilar metal (brass/steel) mating surfaces that are not only designed NOT to slip, and with increasing torque causes additional pressure to the surfaces.

Limited Slip additives likely do not work the same with a metal clutch like they would with clutch plates and composite clutch material.

Now, having said all that, I probably wouldn't test my theory on a $5k-10k drive!!

I am using synthetic gear lube in my Bravo. It's NOT an LS type oil

Cheers,


Rick
 
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Tail_Gunner

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Good man i can follow your train of thought somewhat and have used LS in the volvo but dropped it when Don said it was a no no. Actually i hate the stuff smelly sticky and a few other thing's. I would like to use mobil syn oil just for piece of mind but as of now not going to happen.
 

HT32BSX115

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This is is somewhat off topic since the OP wanted to know about going to or from syn engine oil but, I do worry a bit about using the Merc HP oil since it seems to precipitate that "sludge" when it sits for a while.

It probably wouldn't be a problem in the actual drive because the oil in the drive would get "hot" and presumably melt the "sludge".

BUT, the drive lube receptacle doesn't get very hot (or warm)......... I think the "sludge" sitting in the bottom of it could restrict or prevent oil flow into the drive. Last time I used HP and cleaned the receptacle, There was a LOT of that stuff coating the bottom of the container.

Maybe it doesn't hurt a thing, but I have noticed that most of the other synthetic gear lubricants don't appear to produce that stuff.
 

Lou C

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I use the Merc HP in my Cobra and have for about 10 years; never had a problem but obviously no lube bottle to worry about. It's much easier to find than the BRP/Evinrude stuff.
As far as using Mobil 1 or any other gear oil with LS added, if the manufacturer did not recommend it, DON'T use it. LS allows some slip so you don't get chattering on turns in your LS diff; that allows some slip. I don't think you want that in a cone clutch drive.
 
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