Massive oil consumption from towing a trailer

[Ramblejam]

Originally Posted By: OVERKILL
That's not necessarily true. Two different 0w-30's (AFE 0w-30 and AZO 0w-30) have massively different consumption rates in my Expedition.


Again..."in your application"

I'm speaking specifically about the 3.3 in this Caravan when towing. Not an Expedition, nor any other vehicle.

 

[Kuato]

Originally Posted By: CT8
The harder an engine is run the higher the oil consumption will be.


In many cases this is true. Our 04 Jeep Wrangler - since new - has used oil when run on the highway for long periods, but never a noticeable amount when run around town. I'd keep an eye on it though to be sure.

 

[OVERKILL]

Originally Posted By: Ramblejam
Originally Posted By: OVERKILL
That's not necessarily true. Two different 0w-30's (AFE 0w-30 and AZO 0w-30) have massively different consumption rates in my Expedition.


Again..."in your application"

I'm speaking specifically about the 3.3 in this Caravan when towing. Not an Expedition, nor any other vehicle.


Yes, in my application. And this may also be the case in his application. Two different oils of the same weight have no requirement to yield the same rate of consumption, that was my point, you seem to be intentionally missing it

 

[zeng]

Originally Posted By: Ramblejam
Originally Posted By: Oldtom
I run Mobil 1 5 w 30 EP since that weight is specced in the manual.


Sure, but one-size fits all recommendations can often quickly find the limits of their usefulness when operating conditions are outside of normal usage profiles (which I'd argue mountain towing in a Caravan is).



+1

That's the trouble of blindly following a recommendation, without further insights.

Originally Posted By: Ramblejam
Mobil 1 EP is an excellent product, but any 10cSt oil is going to experience usage in your application. Should you be driving like this with any regularity, switching to something at the thicker end of the range (12cSt) would mitigate the issue.



That's a very sensible suggestion I would consider , under identical situations.

Originally Posted By: Ramblejam
Please go back, take your time, and carefully read my post...then read it once more.
"Mobil 1 EP is an excellent product, but any 10cSt oil is going to experience usage in your application."


I would say more of 10 cSt might see usage though , in relation to 12-14 cSt oils, disregarding HTHSv for now.

 

[zeng]

Originally Posted By: OVERKILL
Yes, in my application. And this may also be the case in his application. Two different oils of the same weight have no requirement to yield the same rate of consumption, that was my point, you seem to be intentionally missing it

+1 , sensible point I believe.

 

[mjoekingz28]

I agree with 440Magnum, lets see if it consumes now after it has seen the gauntlet.

Hopefully all will go back to normal. I would hate for that van to be over the hill now that it did some heavy lifting.

 

[Branson304]

I'm going to guess things will go back to normal & consumption will slow now that you're done towing. You ran that engine hard for an extended period of time, I'm not surprised that it used oil. Just keep an eye on the oil level, I'm sure you already do.

 

[RISUPERCREWMAN]

If you want to tow rent a truck & spare your trans.

 

[raytseng]

Originally Posted By: RISUPERCREWMAN
If you want to tow rent a truck & spare your trans.

spare your trans for what end, so you can pass it on to your heirs when you die? Your vehicles serve you, not the other way around.

 

[SatinSilver]

What oil did you top off with? I probably would have used Mobil 1 High Mileage.

 

[Joe90_guy]

There's a European engine test I used to run called the Peugeot TU5. It was once described to me as 'simulating a Peugeot 2O6 pulling a boat up a hill on the hottest day of the century'. That sort of sounds what you're doing. If so, what you want is the lowest volatility oil you can find. If you can't get hold of any of the 'magic' Pennzoil 10W30, then try and find some 20W50 and that should sort your oil consumption problems out...

 

[zray]

Originally Posted By: 440Magnum
I wouldn't change anything unless you see increased consumption back in your regular driving routine. Chances are the extended high-RPM operation sent a lot of oil through the PCV system, there's no reason to assume that it went past the rings or valve seals. Such high RPM for extended periods makes for a lot more oil mist floating around the crankcase, sucked out by the PCV system, and burned.



There won't be much oil or anything else being sucked out of the crankcase during the situation described by the OP. WHY ? Because the PCV system depends on engine vacuum to do sucking. And there isn't much engine vacuum at any rpm when the throttle is wide open. Put a manifold vacuum gauge on the car and you will see little to no vacuum when the throttle is open wide at any rpm.

. That's why race cars just an exhaust crankcase evacuation system and not a traditional PCV system, the exhaust driven system works all the time, not just when there is a high engine vacuum.

Z

 

[Shannow]

Originally Posted By: Oldtom
Good Afternoon - I have a 2004 Dodge Caravan 3.3 liter v6 automatic. I run Mobil one EP and a Mopar filter. I had 3000 miles and 5 months on the oil change when I towed a 1300 pound trailer into the North Carolina mountains. The roads were so steep my tach was at 5000 RPM to maintain any speed at all. On the way back, I checked the oil and found it one quart low. I added a quart of oil ( Thanks Walmart ! )
.
.
.
THANKS IN ADVANCE FOR ANY ADVICE


I wouldn't worry about it, not change a thing.

I'm guessing that the engine normally runs around 2,000-2,500 in your normal usage...5,000 changes things heavily, inertial effects are not linear.

Your rings do a different "hoochey cooch" (to quote Smokey) at those sorts of RPMs, and will let more "stuff" through.

Rings will allow more blowby, and while that's happening, more oil is getting through the other way too.

 

[Shannow]

Originally Posted By: zray

There won't be much oil or anything else being sucked out of the crankcase during the situation described by the OP. WHY ? Because the PCV system depends on engine vacuum to do sucking. And there isn't much engine vacuum at any rpm when the throttle is wide open. Put a manifold vacuum gauge on the car and you will see little to no vacuum when the throttle is open wide at any rpm.

. That's why race cars just an exhaust crankcase evacuation system and not a traditional PCV system, the exhaust driven system works all the time, not just when there is a high engine vacuum.

Z


PCV closes on high vacuum to limit the flow...at no vacuum, it is wide open, and crankcase pressure pushes the blowby into the manifold, just like the old walking stick breathers used to do.

 

[Jetronic]

Originally Posted By: Joe90_guy
There's a European engine test I used to run called the Peugeot TU5. It was once described to me as 'simulating a Peugeot 2O6 pulling a boat up a hill on the hottest day of the century'. That sort of sounds what you're doing. If so, what you want is the lowest volatility oil you can find. If you can't get hold of any of the 'magic' Pennzoil 10W30, then try and find some 20W50 and that should sort your oil consumption problems out...


How many leaky headgaskets did it get? there's an o-ring in one corner of the gasket which starts leaking on nearly all TU engines...

 

[Joe90_guy]

About the only thing I can remember about the TU5 test was that the engine exhaust pipe was purposely relocated to run directly under, and almost touching, the oil sump. With the engine run flat out for 72 hours, sump temperatures soared! What you got was a classic 'oil stripping' test. If you had a paricularly volatile oil, you could almost empty the sump before the test finished! (typically you would loose oil pressure before all the oil was gone.)

 

[Shannow]

OP, found this which may help

http://ftp.astmtmc.cmu.edu/docs/gas/emissions_task_force/minutes/20060504/sae2004-01-2909.pdf

Again, I think it's your towing (load), and RPM...nothing to worry about.

Joe90_guy fig 19 describes you test...difference in consumption between oils of differing volatility.

 

[Joe90_guy]

I have read this paper endless times. It's a bit like reading John Le Carre's 'Tinker, Tailor' because every time I read it I understand just that little but more! I wish these MIT guys had covered the volatility/oil consumption thing in more detail to broaden the NOACK range and also relate evaporative oil loss to inlet deposits.

 

[440Magnum]

Originally Posted By: zray
Originally Posted By: 440Magnum
I wouldn't change anything unless you see increased consumption back in your regular driving routine. Chances are the extended high-RPM operation sent a lot of oil through the PCV system, there's no reason to assume that it went past the rings or valve seals. Such high RPM for extended periods makes for a lot more oil mist floating around the crankcase, sucked out by the PCV system, and burned.



There won't be much oil or anything else being sucked out of the crankcase during the situation described by the OP. WHY ? Because the PCV system depends on engine vacuum to do sucking. And there isn't much engine vacuum at any rpm when the throttle is wide open. Put a manifold vacuum gauge on the car and you will see little to no vacuum when the throttle is open wide at any rpm.

. That's why race cars just an exhaust crankcase evacuation system and not a traditional PCV system, the exhaust driven system works all the time, not just when there is a high engine vacuum.

Z



There's still PLENTY of PCV gas volume flowing at high-RPM high-load. The 3.3 Chrysler doesn't have a CCV system with a fixed orifice flow restriction like a Jeep 4.0, it has a true PCV system. The PCV valve provides a variable restriction- high restriction under low-load/high manifold vacuum conditions to limit flow, and then virtually an open pipe to maintain the flow when the manifold vacuum drops. Combine that with all the extra oil mist in the air, and you get a huge apparent increase in oil consumption. That's why guys with high-performance engines put PCV oil catch-cans in place... and those DO fill faster under hard driving than under mild driving.

 

[zray]

Originally Posted By: Shannow
Originally Posted By: zray

There won't be much oil or anything else being sucked out of the crankcase during the situation described by the OP. WHY ? Because the PCV system depends on engine vacuum to do sucking. And there isn't much engine vacuum at any rpm when the throttle is wide open. Put a manifold vacuum gauge on the car and you will see little to no vacuum when the throttle is open wide at any rpm.

. That's why race cars just an exhaust crankcase evacuation system and not a traditional PCV system, the exhaust driven system works all the time, not just when there is a high engine vacuum.

Z


PCV closes on high vacuum to limit the flow...at no vacuum, it is wide open, and crankcase pressure pushes the blowby into the manifold, just like the old walking stick breathers used to do.


Correct, but those old vent tube breathers (also called draft tubes) were notoriously ineffective at letting the crankcase do the "push". Ha ha. I should know, I ran one on my 289 HiPo for years recently. The sound you hear is me coughing.

And a PCV system without the vacuum pulling the crankcase clean is just as bad.(ineffective).the orafice of the PCV is designed for a vacuum, the pressurized crankcase is not goiing to be doing any amount of effective venting without a vacuum pulling it. Proof: check out those leaking valve cover gaskets and crankcase seals after a hard run around the track or highway. That's were the excess crankcase pressure is going, not much in comparison is making it thru the PCV. The very same (unchanged) gaskets and seals are later dry under normal circumstances when there is a vacuum.

Z