Lost Oil & Blew Oil Filter Only After Towing With 2012 Toyota RAV4, I'm Perplexed, Cause? Please Read.

[MonteCarlo1987]

Hello. I have a 2012 AWD Toyota RAV4 Sport Edition that has over 84,000 miles on it and 2.5L 4-cylinder engine. I have had it for over 2 years now and bought it used with only 62-63,00 miles on it from a reputable Toyota dealer in NYS. It has been a good car thus far. Right after I bought it, I installed an aftermarket Draw Tite 2-inch x 2-inch tow hitch with wiring harness kit, had it installed by my cousin. With this 2012 AWD Toyota RAV4, I only towed using my Carry On 4x6 foot steel utility trailer with mesh floor a couple of miles around my home with some light items to a local steel recycling center and dump a couple of instances in the past. I have added some photos of the Carry On 4x6 utility trailer for your inspection to get an idea what my utility trailer looks like. I had customized the utility trailer with aluminum walls and some wooden framework 14 years ago as I have used this customized utility trailer with my former 2002 AWD Toyota RAV4 Limited Edition 2.0L 4-cylinder with no issues at all! After installing an aftermarket tow hitch too on my former Toyota 2002 RAV4, I had driven that RAV4 all over the US Northeast with utility trailer in tow without issues.

Now, on Friday, July 26th, 2019, was the first REAL towing I have done with my 2012 Toyota RAV4 and this very utility trailer. I had a small amount of garage sale stuff I was towing to a family member's house 40 miles away. I had 1 additional passenger in the RAV4 with a few small items in the trunk area too. I was driving on a main interstate highway traveling approximately 60-65 MPH most of the way. At first, things were fine, until the last 15 miles of the drive when I started to hear a low hum coming from the engine and getting gradually louder with each passing minute and each mile. The last 15 miles of the drive also had 5 steep hills on the interstate and when I drove up each hill, the engine hum got louder and eased off when I came down the hill. Overall, the hum got exceeding louder. I got off the exit for my family member's town and my car was about to stall with a few shutters with the oil light on the dash’s instrument cluster started flickering signaling oil issues. I drove the car to my family house only a half-mile away and stopped the car and turned off the key. In their driveway, the oil light was steadily before I shut off the car. I saw some smoke vapors coming from the hood and looked under the car and saw from the oil filter back oil sprayed all over the car. A few remaining drops of oil dripped on their driveway. I had the car towed to a local reputable garage where they later determined that the oil filter "blew" and oil itself blew out the O-ring out between the cartridge style oil filter and the lower oil filter threaded mount on the underside of the RAV4. The garage replaced the RAV4's cartridge with a new oil filter and new oil. I test drove the car after I left the garage and the car sounded and ran just fine as if nothing happened! Luckily, I did not cause any damage to the engine with no oil in the engine the final leg of the journey! The mechanic could not answer why this happened to my RAV4 and he was baffled to explain why. The mechanic never heard of anything like that happening before. IT IS OBVIOUS, MY RAV4 MUST HAVE HAD OIL PRESSURE INCREASE TO BLOW OIL OUT AROUND THE O-RING ON THE OIL FILTER CARTRIDGE? …LIKEY FROM TOWING MY UTILITY TRAILER, MAYBE? PEOPLE I HAVE SPOKEN WITH ASSUME THAT MY UTILITY TRAILER IS FINE TO TOW WITH MY 2012 TOYOTA RAV4, IS IT?

NOTES:

a. NO check engine light came on the entire time when I was towing the utility trailer with my RAV4.

b. The coolant meter level on my dashboard’s instrument cluster was normal the entire drive. A matter-of-fact, it was halfway between hot and cold on the dial; typically where it is when I do not tow with the RAV4. Therefore the engine did NOT overheat.

c. I had my last oil change 3-4 weeks ago and I did it myself knowing and recalling that I did tighten the oil filter cartridge against the underside of the motor. Therefore it was not loose.

d. I had driven the RAV4 over 1,800 miles since my last oil change 3-4 weeks ago (without ever once towing the utility trailer) driving up and down some very steep hills on vacation in nearby states without any issues.

e. I have never had the utility trailer weighed after it was customized, I would guess with all the customizations I have done to it; it would weight around 700 pounds.

QUESTION:

SO, WHAT DO YOU THINK HAPPENED? WHY DO YOU THINK THIS HAPPENED? I DO NOT NEED TO DESTROY MY TOYOTA RAV4 ENGINE IF IT WAS THE TOWING THAT CAUSED THE ISSUE! Too much weight for my 2012 Toyota RAV4 to tow? I find that strange that my 2012 RAV4 would have issues towing when my former smaller 2002 RAV4 with a smaller 2.0L 4-cylinder engine towed just fine without issues and I had just as much other stuff in my utility trailer as this RAV4 towed that very day. I have attached a copy of the car identification sticker for your inspection from the inside driver’s door panel on my 2012 RAV4’s GVWR and GAWR on weight capacities. I hope with all this information, you can tell me what likely happened and why?

RIGHT NOW, I HAVE THE TRAILER AT MY FAMILY MEMBER’S HOME. I AM SCARED TO DEATH TO TOW IT BACK TO MY HOME FOR FEAR I COULD NEXT TIME BLOW AND DAMAGE MY RAV4’S ENGINE!!!

[Mike169]

Hi Troy.

First and foremost was the oil filter you fitted a genuine Toyota oil filter you fitted?

A car engine I once rebuilt for a garage, well the customer supplied us with a 'copy part' oil filter and it split at the seam that goes adjacent to the engine so the engine dumped all of it's oil in less than a minute.

The customer came back with another 'copy part', oil filter the thread was the same, screw on type, but it didn't have a non return valve inside and he was, the customer, moaning about the big ends etc were noisy upon start up so I simply fitted a genuine oil filter and all was sorted.

Hope this helps and a reply will be most appreciated.

Regards, Mike.

[Notoyboy]

Rather like Mike, I'd concentrate on the oil side/aspect.  IMHO, I don't think your towing a trailer had anything to do with the problem.  There was no increase in engine temperature, which would have suggested the engine was working harder, and even if it were, the fan(s) would come on, or you'd ultimately stop to allow things to cool down.

Questions:  Regular oil changes?  I'm wondering if somehow an oil line could have become blocked, or the pressure relief valve was misbehaving somehow.  When did you last check the oil level prior to the fateful trip - any possibility of fuel leaking past rings causing increased oil level and higher pressures in the crankcase (although I can't see how this could cause the oil filter to burst).

What was the oil level after you'd switched the engine off, as you lifted the hood, or had most of it been lost?

Good luck with tracking down the problem

[bobby boy]

Get your garage to check the oil pressure by fitting a temporary gauge, making sure it matches manufacturers specifications and confirming the relief valve is working correctly. If the relief valve is sticking shut it could cause excessive pressure to blow the filter.

[Bernard Foy]

Like previous posts, towing the the trailer had absolutely nothing to do with the unfortunate event of oil loss. That car is more than capable of towing that weight. When changing the oil filter previously the large o ring may not have came off with the old filter and was stuck on to the car, and so you might have ended up with two o rings which when under pressure could caused the oil leak. Therefore gradually losing oil and eventually the filter working loose and blowing off. That could be another explanation for your oil loss. 

[MonteCarlo1987]

@ ALL That Have Responded So Far:

 Hello. Nice to meet you all!

Okay, I am going to respond and answer some of your thoughts and questions. I need to get technical as I now see what may have likely happened!

TO MIKE169: Good point. I used a FRAM oil filter for my RAV4, their high grade one that a popular auto parts store in our area sells. Yes, it is not a true OEM Toyota oil fitler, but it is a named brand one. Thanks!

TO Notoyboy:  Yes, I give the RAV4 every 3-4,000 miles consistently. Oil line or pressure release value blocks and malfunctions were later considerations too. However, my RAV4 runs great AFTER the oil change was done – THUS FAR?  Lets hope! Oil level checked a couple of days before trip. Following pulling my key from the engine in my family’s driveway, it was practically empty with only a few remaining drops onto their driveway. Stopping the engine any later would have definitely damaged it! I am very lucky to name the least! Thanks!

TO bobby boy:  Like Notoyboy asked, I thought the same thing with the pressure relief value soon afterwards. Like I said, the RAV4 runs fine now. If this issue were still present, I would be having oil pressure issues now. Thanks! 

To Bernard Foy: When I changed the oil, when I removed the oil filter canister system (I will address in a minute below.), I made sure the O-ring was removed and replaced on the oil filter canister system. Yes, I can see how that can cause issues if it is NOT replaced, especially over time as it becomes distorted. I recall both O-rings pop off or spring out at me when I take off the oil filter canister or the bottom of the engine oil filter drain plug. There is so much that can now go wrong now with the more minute parts that need to be carefully performed with an oil change than the simple old metal oil spin-on filter of yesterday. I see lawsuits on the rise with those oil change places to take your vehicle to. That is why “I” do my own oil changes and no one else, except my cousin who I TOTALLY trust. I have seen that 10-15 minute oil change places do them and they ruin the threads on my oil drain plug on past cars I have owned. However, if this happened where I did go through an oil change place WITH ENGINE DAMAGE, I could have sued them for damages for a whole new engine replacement. Doing it myself is more of a piece of mind, especially now with all the intricacies now with things we buy; BUT I CANNOT SUE MYSELF, RIGHT?

FOR ALL:

The reason I THINK what happened as I have spoken with others with deep discussion I wish to share with you now as it gets technical and it must in order to understand this:

I did NOT torque my oil filter canister system. I am thinking this now as it has come to me… …but I do NOT think the cause of the reason the oil filter canister was not tightly or improperly threaded onto the threaded spindle from under the engine. I did indeed tighten the oil filter canister system against the threaded spindle with my typical extra quarter turn. This would take into account the needed extra tightening to seal the oil filter canister system against the engine. I am sure the leak would have not come from there.  HOWEVER, THERE ARE TWO (2) AREAS THAT NEED TO BE “PROPERLY” TIGHTENED (TORQUED) WHEN IT COMES TO THE OIL FILTER CARTRIDGE SYSTEM!!!! NOT JUST ONE (1) THAT I AM USE TOO as I just mentioned above and as the old metal oil filter (“spin-on”) cartridge system has been replaced by this oil filter canister system. (By-the-way, I personally hate the oil filter cartridge system and wish we would keep going with the spin-on oil filters; but the environmentalists would argue of their disposing of them in landfills is not good for the environment! They are right, so need a way to remove the paper/cloth-like material inside a spin-on filter, separate the metal (recycle) from the filter material, and then STILL BUY THE WHOLE spin-on metal/filter material oil filter again.) With the old metal filter spin-on cartridge where one just threads the metal filter cartridge on a spindle at the base of the engine and tightens it as I was focused tightening with the new oil filter canister system somewhat overlooking the tightness of the ENGINE OIL FILTER DRAIN PLUG (NOT THE SAME AS THE OIL PAN DRAIN PLUG WE ALL KNOW ABOUT) at the bottom. With this new oil filter canister system that Toyota started in most of their cars in 2009, there are TWO (2) parts that need to be properly tightened. That is, engine oil filter canister AND the one I am not considering at the time -- the engine oil filter drain plug!!! Yes, the engine oil filter drain plug located at the base of the engine oil filter canister, also has an O-ring as well to seal the oil from escaping at the base of the engine oil filter canister. The mechanic never alluded to the fact about the latter one, and I did not torque that latter one to specifications too, only hand tight and then turned the engine oil filter canister at top until hand tight then followed word of mouth instructions from mechanics similar to the older simpler metal oil filter cartridges to turn it a quarter turn with an oil wrench after being hand tight. The engine oil filter drain plug threading IS INDEPENDENT from the engine oil filter canister’s threading when loosening and tightening! The Toyota oil wrench fits over the oil filter canister system’s tabs and never comes in contact with the engine oil filter drain plug. I did not tighten to torque specifications on the engine oil filter drain plug then that could have gotten loose over time as the oil filter drain plug was only hand tightened. I cannot believe in my right mind that the sheer tightness I placed on the oil filter canister against the engine would of in any sense of the word, loosened at all! So I have now learned, not only torquing ONE (1) at engine oil filter canister at top, but also torquing the oil filter drain plug as well (part of the engine oil filter canister) at bottom. I am sure I just hand tightened the oil filter drain plug with much less care I placed on that one over the engine oil filter canister is more likely where the oil loss came from. NOTE: I have never had a problem with my quarter turn method keeping the oil filter and even now this oil filter canister on the engine. It is tight! For each oil change so far, I have to use a breaker bar to loosen the oil filter cartridge. That is how tight that one is! So let this be a lesson to all of you too! Watch out for the bottom engine oil filter drain plug too!

[Notoyboy]

Thanks for sharing your thoughts with us.  I've not come across an oil fliter drain plug like you describe.  It's certainly a possibility that it was the culprit, and I guess only time will tell.

Fingers crossed that the engine now runs just like it always did ☺️