V6 4runner with engine whine

[DRC]

I originally posted this under the 4th gen board but did not have any luck. So I am trying my luck here in the general area. I don’t know if you can move a thread, so I am just cutting and pasting…


Okay, now this is starting to bug me a bit. About 3 weeks back I finally got around to installing an engine oil cooler. I am using a Glowshift sandwich adapter at the oil filter and have AN-10 lines running to my cooler core. Anyway, at this same time I started noticing a whining sound coming from my engine. Prior to installing the cooler I never noticed this whine but it is possible that it could have started sometime over this past winter before I installed the cooler and I am just hearing it now since it’s starting to warm up and I have had the windows down, etc.

I have a 08 v6 with 33,000 miles on it and the whine is more like a whirring sound. It sounds like I have a blower. Whish I did. The sound is very noticeable between 5mph and 40mph and most noticeable during deceleration in this speed range. When I am coming to a stop, after removing my foot from the gas, you really hear the whine. You know how when you take your foot off the gas and the RPM’s drop down then kick up a little bit around 1,000rpm, this is where the whine really can be noticed. My 12 year old son keeps asking me what’s wrong with my car? Once I come to a stop the whine starts to fade away slowly while idling. Also, the whine can be heard if I am in park or natural and hold the engine stead at about 1,500rpm’s so it’s not coming from the tranny.

I have found some other posts on the board about 4runners making a similar whine but these seemed to be related to a faulty belt tensioner, worn serpentine belt, bad alternator and a few unknown reasons. I have inspected all of these and everything seems to be in good working order. I can’t seem to find where the whine is coming from. I have had my head under the hood while the wife held the engine at 1,500rpm’s and I could hear the sound but could not find the source. It almost sounded like the noise was coming from the oil cooler lines. Is this possible? Can the sound of oil pumping through the lines / cooler make this kinda sound? Is this just a common 4runner sound that I am just noticing now and should not worry about?

Has anyone else heard this whine? Is this a normal sound for a v6 4runner?

 

[DRC]

Okay I have a little more info on this. What I have observed is that the whine does not immediately happen when I first start driving. It seems the engine starts whining only after the engine is fully warmed up. Say 10 – 15 minutes for driving. Only after the engine is hot do I start hearing the whine.

 

[CJ3Flyr]

Any pics of the install? If you did an install post just give me a link. Is the cooler like a trans cooler (in front of the A/C condenser)?

 

[DRC]

Any pics of the install? If you did an install post just give me a link. Is the cooler like a trans cooler (in front of the A/C condenser)?

Yeah, that post is in progress…like a goof I took pics of the install then decided to send my camera out to be cleaned with the memory card still in it. Do’h.

Anyway, I just got my camera back so here are some pics of the oil cooler.

http://www.toyota-4runner.org/attachment.php?attachmentid=28577&stc=1&d=1273113665
http://www.toyota-4runner.org/attachment.php?attachmentid=28578&stc=1&d=1273113681
http://www.toyota-4runner.org/attachment.php?attachmentid=28580&stc=1&d=1273113688
http://www.toyota-4runner.org/attachment.php?attachmentid=28581&stc=1&d=1273113695

 

[CJ3Flyr]

:jaw drop: That is a super-sweet install! I am totally jelous:thumb3:

My guess is as follows: The oil cooler is "dumping" heat (a good thing). Because of that the air flowing over the fan-clutch is a few degrees hotter; enough hotter to make the fan engage more. In the end game it's probably all good. If I had your setup I'd seek a 180degree t-stat. That would help to put a greater margin between open t-stat and fan engagement. You lost some of that "margin" when you started dumping hot air (oil cooler) in front of the condenser.

That just a semi-educated guess... Keep us posted.


You have to go to the mod sticky in General and post a link!

PS- That's exactly the cooler I have on my trans.

 

[DRC]

CJ3Flyr, I wonder if you could be on to something here. The cooler gets mighty hot. I would bet about 200 degrees or so. Hot enough to just be able to touch it for about 30 seconds or so before you need to pull your hand off. Much hotter than I expected. I do feel the heat being pulled off it if I put my hand between the oil cooler and the condenser core. A good thing.

So the idea is that the fan is engaging more since its “feeling” more heat? Is my understanding right? I have heard a few people talking about putting in a 180 t-stat with other mods but I never thought about that. Do you know what the stock t-stat is set for?

 

[CJ3Flyr]

So the idea is that the fan is engaging more since its “feeling” more heat? Yes! Is my understanding right? I have heard a few people talking about putting in a 180 t-stat with other mods but I never thought about that. True. Do you know what the stock t-stat is set for? 192F or 195F, I don't remember. It's something that converts to a nice, round metric 'C' value that's very close to 200F.

:cheers:

 

[CJ3Flyr]

This is great read on the fan-clutch: Tuning and Understanding your Toyota Viscous Fan Clutch Paul’s esoteric meanderings

 

[DRC]

Very interesting read on the fan clutch. I never know they were that complex. I guess since I have been driving it now for about 4 weeks and have put on over 1000 miles without any trouble, except the whine, I should be okay. Nothings broken that I know of. At some point I will most likely swap out the t-stat for the 180 but for now I am moving on to doing my brakes. Getting ready for a Yellowstone trip this June and want to have everything in tip top order. I will post back if anything changes.

Thanks for the advise.:hatsoff:

 

[DRC]

Well I have some more information on my whine. This whine sound is annoying me to the point that I decided to recheck my oil cooler install and confirm that the oil was flowing smoothly, no obstructions, and in the correct direction. See, I was never really 100% sure I had the oil flowing in the correct direction. That is, in the top of the cooler and out the bottom. When I was researching the topic I could not find any info on which direction the oil flowed through the oil filter. After looking at everything for a while I concluded that the oil must flow up the center hole, through the filter and down the small collection hole. I called Glowshift, the maker of my sandwich adapter, and asked how this worked and the person I spoke with confirmed the oil flowed up the center hole also. So I did the install based on this information.

This past weekend, I had the brilliant idea to disconnect the “in” line of the sandwich adapter and start the engine and watch the oil flow to confirm everything was working as intended. So I placed a large collection container under the “in” line and figured I would just place a rag near the inlet of the sandwich adapter just incase a few “drops” of oil came out. Notice my use of quotes around “in” and “drops”. That is important…

I had the wife start the truck and oh shit!! That’s not the in line…it’s the out. Within about 3 seconds I had about a quart of oil splattered all over my engine, all over my fenders, on my driveway, in the grass on the wife’s car and all over me. I said it was a brilliant idea! Note to self…don’t ever do that again.

Lessons learned:
1) I am an idiot!
2) The oil flows from the small outer hole through the outside of the oil filter and down the center hole back to the engine.
3) The folks that answer your questions about the products they sell don’t know jack.
4) I am an idiot!

So, turns out I had my oil flowing in the wrong direction. It was flowing to the bottom of the cooler core, up the core and out the top and back to the oil filter. After spending another 3 hours scrubbing my driveway and washing both cars I swapped the lines so the oil flowed in the top of the core and out the bottom then back to the filter.

Surprisingly, for the next 2 days my engine was humming like a kitten, nice and quite. Was this the case of my whine? Too much backpressure on the oil pump trying to pump the oil up the cooler then through the filter? Well maybe.

On the 3rd day after my self induced chaos the whine came back. WTF! Interestingly it was a warmer day, near 70 degrees and a little humid. I had mentioned before that the whine seemed to increase as the engine warmed and today was warmer then the other 2 days which were in the mid 50’s to low 60’s when the whine seemed to be gone.

So, I am working on a new theory now. Originally when I had my oil pumping to the bottom of the cooler core it whined every time the engine got hot. Now that I have it connected correctly, pumping to the top of the core and letting gravity help me out, its much quieter but when it starts getting warmer outside it starts whining again.

So my theory is that as the oil viscosity thickens as the engine heats up and the outside temperature warms it gets harder for my oil pump to push it around and I get this whine sound. With the oil pumping to the top of the core it’s a little easier for the oil pump and I am getting less whine while the temp outside is below about 70 degrees and not humid. As the temp outside increases I get more whine.

Can anyone add to my theory or poke holes in it? I am thinking I may want to try going from 5w-30 oil to 5w-20 oil and see what happens but I am not sure 5w-20 would be good when towing. I use conventional oil for my engine btw.

 

[DRC]

Seems I have not gotten any traction on this topic. Is my issue so strange that no one has any suggestions or advise? Or could it be that I am the strange one? I often wonder this myself as I tend to have some of the oddest problems you could imagine. But I digress…

In any case, I have an interesting update. In my last post I was working on the theory that the oil viscosity had something to do with the whine sound I am getting. My theory is as the oil thickened when the engine got up to normal operating temperature the oil pressure increased causing the oil pump to make the whine sound because it was working harder to push the oil around.

After some oil research I decided to give Mobil 1 0w-30 a try. Based on the PDS the 0w-30 has a slightly lower viscosity then Mobil 1 5w-30:

Mobil 1 0w-30:
cSt @ 100c = 11.0
HTHS viscosity @ 150c = 2.99

Mobil 1 5w-30
cst @100c = 11.3
HTHS viscosity @ 150c = 3.09

So if I understand this data, the 0w-30 is just a little thinner then the 5w-30 so it should flow easier. Also based on what all the manufactures claim, synthetic oils have less drag so in general a synthetic should flow better then dyno oil. $65.00 dollars later I had 6qts of Mobil 1 0w-30 and a new Mobil 1 filter in hand and I was about to put my theory to the test.

This past weekend I did a complete brake job, replaced the air filter and changed the oil. After completing all the work I took my truck out for a long drive to test out the new brakes, etc. Guess what?

The engine was as quite as a mouse. It was so quite and smooth it felt like a brand new car. The whine noise was 100% gone. Has my theory been proven? Was the addition of an oil cooler the cause of the whine because of pressure? Well I ruled out the brake job as having anything to do with this so that leaves the air filter, oil and oil filter. I ruled out the air filter as the old one was not bad and I just can’t see this causing this anyway so that leaves me with the oil and oil filter.

Now I thought I had solved the whine before when I swapped the in / out lines on the cooler only to have the whine come back after the engine got hot so this time I decided to wait several days to see if the whine truly was gone. I am on nearly 400 miles or about 1 week of driving and the whine is still gone but not 100%. The whine is more like 95% gone. I say 95% gone because I can still hear a slight whine noise during deceleration from about 30 mph to idle, but it’s slight and goes away quickly once at idle. It’s very subtle though and if you did not know what you are listening for you would not notice it at all. At this time I will say that the whine issue is resolved, knock on wood!

Now was it the oil or the oil filter? Well I am going about 90% oil and 10% filter. When I first installed the oil cooler I left the original oil in the system and reused the Toyota filter as it only had about 3,000 miles on it. I wanted to run the oil through the cooler for a while before changing the oil incase there was any crud in the cooler core / lines. So I drove a few hundred miles and then did a full oil / filter change. New Valvoline 5w-30 dyno and a Fram filter. (Yes I know Fram is bad). After my fiasco a few weeks back, see my last post to this thread, I had replaced the oil filter with another new Fram. So I had 1 OEM filter and 2 Fram filters and all the while I had a whine. Because I had used 3 different filters and this did not change the whine sound I don’t think the filter had anything to do with the sound. But I am not 100% sure of this so that is why I can’t say 100% that the oil was the issue and not the filter.

In any chase, running a Mobil 1 filter and Mobil 1 0w-30 oil has resolved the whine and has given some truth to my theory. It seems the slightly thinner 0w-30 oil and the fact that synthetic oil flows better has reduced the friction in the oil system and eliminated the whine noise.

Does anyone have anything they can add or can anyone dispute this as a coincidence? Just want to hear what others think.

 

[CJ3Flyr]

:jaw drop:WOW! That's a great post and very interesting. That's amazing that such a small difference in viscosity makes a difference.