Transmission oil to cure engine oil consumption?

[luckyluke]

Almost afraid to ask but.....

I mentioned to my mechanic my 3.7L was consuming some engine oil; not real bad about a quart every 5 hours or so. I assumed the rings weren't in the best shape.

He advised to dump a quart of transmission oil in next time it was down. Good for valve seals, etc...

Haven't done it yet as I've always been leery of quick fixes or the "mechanic in a can".

Any thoughts or experiences to share would be appreciated.

Thanks,

 

[bonzoscott]

Re: Transmission oil to cure engine oil consumption?

That could possibly loosen some stuck rings but would do nothing to your valves. You'd have to pour TF in the carb to reach the valves. Is it burning the oil? Do you see smoke?

 

[haulnazz15]

Re: Transmission oil to cure engine oil consumption?

1Qt every 5 hours seems like a good bit of oil burn. I'd suspect some rings are damaged, and it's not likely ATF is going to solve that. If you had some really leaky valve stem seals, the ATF may help some, but again, not likely enough to cure that much oil consumption.

 

[oldjeep]

Re: Transmission oil to cure engine oil consumption?

Transmission fluid is an excellent cleaner, I use it to free up siezed motors. Normally I wouldn't suggest sticking anything in the oil to try to solve burning issues - but if you are actually burning a quart in 5 hours then the motor is done for anyways so it probabally wouldn't hurt to try.

 

[HT32BSX115]

Re: Transmission oil to cure engine oil consumption?

Almost afraid to ask but.....

I mentioned to my mechanic my 3.7L was consuming some engine oil; not real bad about a quart every 5 hours or so. I assumed the rings weren't in the best shape.

He advised to dump a quart of transmission oil in next time it was down. Good for valve seals, etc...

Haven't done it yet as I've always been leery of quick fixes or the "mechanic in a can".

Any thoughts or experiences to share would be appreciated.

Thanks,

yeah. jeeze........There is NO "mechanic-in-a-can". (period)

There's is no evidence that hydraulic fluid can do anything when dumped in your oil except dilute it!

Dilute it enough and you run the risk of breaking loose sludge or other particulates. If they break loose anyplace AFTER the oil filter, they could become lodged in an oil supply gallery. If that happens before a bearing, the resulting spun bearing could lead to a seized bearing. Everything does down hill from there if you keep running the engine.

Hydraulic and automatic transmission fluid is for hydraulic systems and automatic transmissions.

NOT for reciprocating engine crankcases.


I'd find another mechanic though......your current one is really no better than a mechanic in a can...........

 

[Walt T]

Re: Transmission oil to cure engine oil consumption?

And yet auto parts stores make tons of money selling that stuff. Oil treatments that will rebuild your engine as you drive it, Cooling system stopleak that will fix head gaskets... Big money in this stuff

 

[minuteman62-64]

Re: Transmission oil to cure engine oil consumption?

Back in the 1970's one of my co-workers took an automotive repair course at a local JC. The instructor, an old time mechanic, advocated once every 2-3 years draining the crankcase oil, filling with ATF and driving for 200 miles. Then drain the ATF and replace with regular motor oil. He maintained that would keep the internal passages of the engine block clean.

My co-worker and I both did it once. I did it with my 1968 Cougar (50K miles at the time) with no apparent ill effects - it was running strong (w/different owner) till the early 1980's. He on his '67 Dodge. Then I lost my nerve and didn't do it again. I don't think my buddy did either.

That was a different breed of engine. With today's tight tolerance engines I'd never be so bold.

 

[HT32BSX115]

Re: Transmission oil to cure engine oil consumption?

And yet auto parts stores make tons of money selling that stuff. ..................Big money in this stuff

Never said there wasn't an abundance of people dumb enough to buy Snake oils!

The instructor, an old time mechanic, advocated once every 2-3 years draining the crankcase oil, filling with ATF and driving for 200 miles.

.................................. AND plenty of people dumb enough to advocate using "Snake Oils"

Many people still advocate using Marvel Mystery Oil and Slick-50!! and cite "examples" (testimonials) of how "great" it works!!

My co-worker and I both did it once. I did it with my 1968 Cougar (50K miles at the time) with no apparent ill effects - it was running strong (w/different owner) till the early 1980's. He on his '67 Dodge.

Most hydraulic and AT oils are roughly equivalent to a light motor oil. (10W, 20W etc) You wouldn't immediately harm any otherwise normal operating engine running them on a very light oil for only a "few" miles.

(My old 57 Ford specified 20W-20 oil in the owners manual)

The problem lies with the additive package in hydraulic oils for extended use. They’re not designed to be burned in an internal combustion engine ........and the detergents are all wrong. It would still provide some lubrication for plain bearings and cyl walls.

Also, in an engine that has not had the oil changed regularly and/or maybe used non-detergent oil in it's past, might have "deposits"(sludge) built up inside. while some might think it's good to remove the sludge, (and it is good) It's NOT good to remove the sludge quickly when the engine is running because it might come off in "chunks"............and those chunks might go someplace you do not want them to go at the wrong time!!

It's FAR better to clean that "sludge" manually and once clean, change the oil regularly. (use "real" motor oil. nothing else!)



To the OP,

If you want to "cure" excessive oil consumption, fix the engine. Use ATF in your car.

 

[crazy charlie]

Re: Transmission oil to cure engine oil consumption?

To help you cause I would recommend using minimum sae30 weight oil. Sae 40 may reduce oil burning.DONT use a multigrade.Avoid any additive that will thin the oil weight like tranny fluid.Charlie

 

[rallyart]

Re: Transmission oil to cure engine oil consumption?

My 470 burns a little less oil than that. It's got about 3000 hours on it and has only been under water once. Mine smokes some.
The oil can leak past the valve seals which can be replaced without to much work. The oil can leak from the engine into the bilge past a gasket or seal which would be more work. The oil can leak past the rings which takes a rebuild to fix.
To lessen the leaks use a 40 weight oil, like Charlie suggested. (I use multigrade synthetic in everything else I own.) Don't worry about every additives. They just add to the cost.
You might want to do a leak down test on the engine to see what the rings are really like. I'm not sure it's worth rebuilding a 470.

 

[luckyluke]

Re: Transmission oil to cure engine oil consumption?

To help you cause I would recommend using minimum sae30 weight oil. Sae 40 may reduce oil burning.DONT use a multigrade.Avoid any additive that will thin the oil weight like tranny fluid.Charlie

I've been using the Mercruiser recommended 25W40............ this is wrong?

PS: I may have overestimated oil consumption in the motor; I don't find it's that bad, I just check my oil regularly and top up when necessary. PPS: It probably burns less oil than my 2010 Dodge Grand Caravan with the 4.0 of which the dealer responded "anything less than 1L per 800 kms is deemed acceptable by Chrysler"; but that's another story...

 

[HT32BSX115]

Re: Transmission oil to cure engine oil consumption?

I've been using the Mercruiser recommended 25W40............ this is wrong?

PS: I may have overestimated oil consumption in the motor; I don't find it's that bad, I just check my oil regularly and top up when necessary. PPS: It probably burns less oil than my 2010 Dodge Grand Caravan with the 4.0 of which the dealer responded "anything less than 1L per 800 kms is deemed acceptable by Chrysler"; but that's another story...

No. It's not wrong. people who generally advise against using a multi-grade oil are simply parroting the mantra of the "old days".

Old timers have been telling people not to use multi-grades since their inception! There are absolutely good reasons to use multi-grades in cars.

This is not a car however, BUT Both Mercury and Volvo recommend (very specific) multi-grades for their engines.

You can go over to the SAE API and ASTM sites and read through many technical papers on the subject. Or you can read through many manufacturer info sites or even "Bob is the Oil Guy" info and find largely the same thing.

Wikipedia has an excellent article that has info taken directly from the SAE, API, and the ASTM.

Bottom line is for most all boats, you do not "need" to use a large viscosity spread multi-grade synthetic in a marine engine. The lowest temp that would receive max benefit from using the oil would find the boater FROZEN SOLID in the marina unable to move!!

Since you do not need that LOW temp "capable" oil, smaller spread multi-grades (like 25W-40 etc) or single grades are much more desirable.

The MAIN desirable characteristic of ANY multi-grade is LOW temperature "pump-ability". That is essentially, during cranking and initial start-up, the oil FLOWS through the smallest oil passage. .............

With a single grade SAE 30 for example, at -30F, the oil is literally like grease. you might see oil pressure at the gage but the oil is going NOWHERE and you have plain bearings and other lubricated items getting no pressurized oil at all until the oil starts moving. SAE 0W-30, 5W-30, 10W-30 etc, flows at LOW temps (nearly) as good as it does at 100C (where the viscosity is measured btw)You do not have to do ANY of the above "homework" by the way.......you can just use the oil recommended by the engine manufacturer and you'll be fine.You can also read through the thousands of forum posts, or ask in the forums and you'll get NO END of suggested oils to use..... AND to be fair, they've all been tried...... pretty much successfully I might add.Marine engine failures are largely due to poor (or NO) maintenance......... NOT due to the type of oil used.......

Here's what the marine engine manufacturers suggest:

Oil information - Oil information : Volvo Penta

MerCruiser Fuel & Oil FAQs | Storage & Maintenance MerCruiser FAQs | Mercury Marine

If you have a "catalyst" engine you MUST use the oil (type) recommended by the manufacturer

If you don't have a "cat" engine, you can pretty much do whatever you want.

Bottom line, do what the manufacturer suggests and spend your free time boating instead of worrying about what (snake) oil to use!!
Cheers,


Rick

 

[rallyart]

Re: Transmission oil to cure engine oil consumption?

I'm not parroting 'old days' car stories. I'm a strong advocate of multigrade oil in almost everything. If, however the engine is on the way out the low viscosity of the multigrade at cold temperatures make leaks more pronounced until the engine is up to temperature so you burn more past the rings and lose more past gaskets and seals.
For engines in reasonable condition the number you need to pay attention to is the last number while the first 'W' number can be almost anything but should be no higher than that recommended. In my normal boat with a Mercruiser Scorpion engine I use a 5W-40 instead of the 25W-40 for the reasons of pump-ability and keeping startup wear low. There is no problem with the Mercruiser brand or recommended oil. But I do have an old 470 and know what it does. Fortunately it never runs when it is -30 but I have many other vehicles that do that regularly.

 

[Silvertip]

Re: Transmission oil to cure engine oil consumption?

Oil consumption can be caused by a number of issues or a combination of them including: 1) stuck rings, 2) worn rings/pistons/cylinders, 3) scored cylinders, 4) worn valve guides and or seals, 5) external leakage (which would be obvious). Nothing you add to the engine oil can fix something that is worn or damaged. The only thing that can be fixed by an additive would be stuck rings and in some cases, valve stem seals but even that is a hit or miss situation. Stuck rings are caused by a number of issues ranging from lack of oil changes to an engine that runs too cool. Marvel Mystery oil and Rislone (just to name two) are products that can help loosen stuck rings. They are also excellent sludge removers and are worth a try if oil consumption is caused by stuck rings. I've used both but my preference is Rislone and it is readily available at most auto stores.

 

[jimmbo]

Re: Transmission oil to cure engine oil consumption?

ATF as mentioned before is not an engine oil. It does not contain Extreme Pressure additives. Those additives are needed to protect the camshaft lobes and lifter faces on engines that do not have roller cams. Worn connecting rod bearings are often the source of high oil consumption. Worn bearings will leak more oil and it will be thrown all around the inside of the crankcase including the cylinder walls. Enough oil and the oil control ring on the piston is overloaded and the excess oil wil get past the compression rings into the combustion chamber