0w20 VOA/UOA differences

[modularv8]

I have an '06 F150 5.4L and after the first start of the day (morning, temps ~ 35F) I can hear the VCT knock slightly when the engine is cold. It is more pronounced under load since the first I thing I need to do to leave the neighborhood is to go up a long hill. Eventually it dimenishes once the temperature gauge is at the quarter mark and is completely gone at operating temperture. Anyway, I'm guessing the oil viscosity (Motorcraft 5w20 blend) at this temperature is causing it.

So here is my question, anyone have this same problem? I was thinking of using 0w20 (HONDA/Toyota/etc) but I've noticed that their VOA shows ~40cSt @ 40C & ~8.7 cST @ 100C and then the UOA will result in ~54cSt & ~7.8cSt at the same corresponding temperatures. This is the typical result for a 5w20. So is there a benefit to using 0w20 for a 5000 oci considering it will shear and thicken to about a 5w20? Maybe I should just let the truck warm up in the garage? Thanks...

 

[Silber Igel]

VCT ??????

 

[modularv8]

Variable Cam Timing. It functions off oil pressure. Known to knock, if oil viscosity is way off.

 

[tig1]

At 35F any oil will should be fine in that engine.

 

[modularv8]

I agree, but it only does the knocking sound when below ~55F. It is disconcerting to hear, makes me think something is getting ruined. At ~55F and below, the truck will rev around 1000 rpms for the first 30 seconds after start then settle down to 850 rpms. At operating temperature, it idles at ~700 rpms. Anyway, any load on the engine (up the hill, accelerating) creates a knock/clack sound. At first, I thought it was a lifter but it only does it at these low temperatures. Just want to see if this is normal for the 5.4L 3v engine. Also, does anyone experience engine roughness/shake at 1700 rpms?

 

[Johnny]

I have no experience with the 5.4L but my 4.6L makes no noise at all. It was 15F here this morning and it was as quite as it was last week when it was 50F. Mine also has the fast idle first thing, then slows down. That's when I start to drive away.

Your Motorcraft 5W-20 should be all you need in that part of the country.

 

[PT1]

I would just let the engine warm up for a few minutes on cold mornings if you are concerned. Thicker oil can negatively effect the VCT and timing which is worse IMO. The VCT in your truck is designed to use with a 5w20 oil.

 

[Bill in Utah]

Originally Posted By: tig1
At 35F any oil will should be fine in that engine.


I agree!

If its having issues with 35f then take it back to the dealer and have them fix it. There will be NO difference between a 5w-20 any oil and 0w-20 at that temp.

Take care, bill

 

[mechtech2]

Your VCT is not operating normally until the engine temperature is up to normal. This is dependent on the coolant sensor.
When it's cold out, this takes longer.
It's not the oil.

 

[CATERHAM]

Originally Posted By: modularv8
I have an '06 F150 5.4L and after the first start of the day (morning, temps ~ 35F) I can hear the VCT knock slightly when the engine is cold. It is more pronounced under load since the first I thing I need to do to leave the neighborhood is to go up a long hill. Eventually it dimenishes once the temperature gauge is at the quarter mark and is completely gone at operating temperture. Anyway, I'm guessing the oil viscosity (Motorcraft 5w20 blend) at this temperature is causing it.

So here is my question, anyone have this same problem? I was thinking of using 0w20 (HONDA/Toyota/etc) but I've noticed that their VOA shows ~40cSt @ 40C & ~8.7 cST @ 100C and then the UOA will result in ~54cSt & ~7.8cSt at the same corresponding temperatures. This is the typical result for a 5w20. So is there a benefit to using 0w20 for a 5000 oci considering it will shear and thicken to about a 5w20? Maybe I should just let the truck warm up in the garage? Thanks...



We will know soon enough how the Honda and Toyota 0W-20's perform in service. In Toyota's case this is now the preferred lubricant for all Toyota's and Lexus' in NA. There are a couple of factory fill Toyota UOA's which use the same oil and the 100C vis is still in the 8.5-8.6 cSt range.

BTW, if an oil shows evidence of shearing at 100C that will be the case at 40C as well, not thicken as you have suggested.

 

[modularv8]

I let it get up to operating temperature, placed in drive with the handbrake and listened around the engine. Noticed that it isn't coming from the VCT, but I can hear a disintive knocking sound from inside the passenger side fender well. It's coming from near the front lower part of the engine and sounds similar to spark knock/detonation but is continuous but not always the same. It's not there when idling unless I rev it, then it is barely audible for a split second. It's not real loud, but it is there if you listen for it and I don't want it to get worse after the warranty. I have 37k on the truck. Ford has a drivetrain warranty of 5 yrs/60k. I will take it in to the dealer. Hope they don't say it's no big deal/normal.

 

[SilverC6]

The location of the knock almost sounds like a main bearing.

Ouch!!!


I'm thinking about moving my Toyota to 5w30 YBP.

I'm growing tired of buying expensive M1 and pouring it into my "economy" car at 5000 mile warranty change intervals.

 

[icruse]

Where is your oil filter located? Is it a Motorcraft filter?
I use an Amsoil EA34 (with the 0W20 Amsoil) in my 01 Windstar and got a knock until it warmed up.
Went back to a Motorcraft oil filter and it stopped.
I was looking in my owner's manual a few weeks later and it mentioned this very sound I was having.

Good Day,
Steven

 

[98dakarM3]

The better you can describe and repeat the noise/knock, the better chance you'll have of getting ford to do something about it.

I think every car-guy should have one of these in his tool box for hunting down noises: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=41966

 

[Bryanccfshr]

I start my 5.4l truck and drive when it is 18 and below every day of the work week and never notice any odd noise. The 4.6 in the explorer never makes noise on cold start either.

 

[modularv8]

I only use Motorcraft filters/oil from a highly reputable Ford dealer (est. 1919) who also does all the oil changes. I have a Harbor Freight in town, so good advice about the stethoscope. And glad to know that this isn't normal, so I can do something about it. I'm going to try to record the sound so the Ford mechanics will know what I'm talking about. Thanks for everyone's input.

 

[modularv8]

Okay, so I refueled and the knocking is gone. Originally had Shell 87, now Chevron 87 octane. Must have been a bad batch of gas that I put in right as the cold weather showed up. So it seem related to the cold temperature. Anyway, I'm glad it runs real smooth and quiet like before.