Synthetic makes 1NZ-FXE louder. More than once

Hello,

i've had several higher mile Prius come in the 1.5 1NZFXE and drained conventional out to put full synthetic and then they are noisier when cold. I assume this is becuase synthetic is more fluid when cold. I was thinking of bumping up to 10w30 full synthetic rather than going back to conventional. Would love to here from you guys

Thanks
They came in warm.

They went out cold.

What you attribute to oil blend could very well be the difference in sound between a cold engine and a warm engine.

Correlation is not proof of causation.
 
No these are vehicles I had for while. The one that inspired me to write this was with me for about 600 miles, on a quick lube style shop oil change. I went with wix and 5w30 HM FS super tech and now mornings below freezing these is a little more clatter than before.

Every previous example had some time with me as well
 
I found the same with Quaker State 10w30 synthetic providing a quiet running engine at all temp.
Castrol Edge made it like all the piston skirts were collapsed and rod caps loosened.
So not necessarily a synthetic attribute - which is a near meaningless term these days, but more at the over all blend and formulation.

Advice? I wouldn't worry too much about a little bit more tappet noise when cold.

Where is Magnatech when you need it! I bet their 5W20 would be quiet without adding drag losses.
 
I went with wix and 5w30 HM FS super tech and now mornings below freezing these is a little more clatter than before.

Drew, I suggest trying Quaker State Full Synthetic 5W-30 with a Fram Ultra filter for your next oil change. This combination has resulted in the quietest startup and running noise for several of the Toyotas and Honda 4 cylinder engines that I have owned or serviced over the past several years. While some have suggested Pennzoil Platinum is similar/identical to QSFS, I have noticed quieter valvetrain noise with the Quaker State oil.
 
Give it a bottle of STP synth. If you add a pint, and noise continues, then it has nothing to do with grades or visc. This way, you don't waste the current fill or filter. Just make room for the pint and toss in the bottle.

The difference among some brands of grade is miniscule. 10w30 is not some automatic fix for 5w30 engines. Study the datasheets. Only a few and specific ones have a drastic enough visc/hths difference. 10w30 is just a fanboy fad bottle label by those don't have a clue concerning HTHS, SAE J300, or datasheets.

The other option is to use the ESP or Euro oils, which are 3.5+HTHS. Pennzoil, Castrol, Valvoline, and Mobil euro-choices are easy enough to find at local autoparts or walmartyr. This way, the label will still save 0w30 or 5w30 if needed. My local Napa and Oreillyauto have the Rotella T6 5w30, and local AdvanceAuto/Carquest has the Delvac1 Extreme 10w30.
The zero w thirties and five w thirties from dexos dos is a good start, even though when oil grade makes a noise, I always skip right to the common 0w40's.

I wonder how many mistake a noise from a pathetic filter too. The Napa silver/gold and Wix regular filters have caused me heartache. If its not an XP/Platinum, then you should consider upselling the customers, or use an OE filter, or stock up on Denso FTF's, or the orange can(if silicone ADBV) The XL filters, like Champ/Supertech/STP/Premiumguard/ecoguard/FVP.... are worth trying for the next service.

BTW, when I hear noisy Toyotas with 'higher' miles on them, I automatically think "IT NEEDS A VALVE ADJUSTMENT". Don't worry. When the exhaust valve burns, or any valve gets dropped, or a spring breaks, you can then address the noise.
 
All very good info thank you. Just to clarify, in the specific case, I think I put a minimum of 600 miles on this car, and in way colder weather than we’ve been having lately… I drove it on the old oil and filter at 6°F. The day after the oil change it was 24°F and I got the clatter. This exact scenario has happened multiple times, usually with the old 1.5 L Prius. I am just convinced they don’t like fall synthetic… Definitely doesn’t need a valve adjustment. So back to the original question, can any harm come from 10 W 30
 
All very good info thank you. Just to clarify, in the specific case, I think I put a minimum of 600 miles on this car, and in way colder weather than we’ve been having lately… I drove it on the old oil and filter at 6°F. The day after the oil change it was 24°F and I got the clatter. This exact scenario has happened multiple times, usually with the old 1.5 L Prius. I am just convinced they don’t like fall synthetic… Definitely doesn’t need a valve adjustment. So back to the original question, can any harm come from 10 W 30
Wasn’t that answered already? The answer is still none as long as the winter rating is appropriate for your expected starting conditions.

And again, no engine is harmed by an oil with a somewhat higher HT/HS. Film thickness protects an engine. It prevents damage not the other way around.

I’ve lost track in this convoluted thread exactly what you were asking, but the winter rating is substantially irrelevant here as long as it is appropriate for your starting temperature. Any oil will be somewhat thicker at 6F than 24F. Plot them out yourself if you don’t believe it.
 
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I guess it was answering ha ha and I certainly didn’t mean that in a rude way, so if it came across that way, please forgive me. And truthfully, I don’t know. Where I live, it occasionally gets down into single digits…
 
I guess it was answering ha ha and I certainly didn’t mean that in a rude way, so if it came across that way, please forgive me. And truthfully, I don’t know. Where I live, it occasionally gets down into single digits…
An oil with a 10W winter rating is suitable for that starting temperature but if it were me I’d use one with a 5W rating in case it got colder.
 
Apparently our recons low was -22°f but the lowest I’ve ever seen is -9°f

Maybe I’ll throw a synthetic blend in it - whatever was in it before was the cheap oil at some southern quick lube shop
 
Drew, I suggest trying Quaker State Full Synthetic 5W-30 with a Fram Ultra filter for your next oil change. This combination has resulted in the quietest startup and running noise for several of the Toyotas and Honda 4 cylinder engines that I have owned or serviced over the past several years. While some have suggested Pennzoil Platinum is similar/identical to QSFS, I have noticed quieter valvetrain noise with the Quaker State oil.
Good point! The QSFS has lots of moly, and high moly is legendary for quietness. PP and QSFS are two completely different oils via analyses.

Out of all the oils I've used in my Accord so far, vanilla M1 5W30 (Dexos Gen 3) is hands down the smoothest and quietest (y)
 
Thanks! It’s also cheap. I can switch it it for all of my cars. Though my personal and collector crap gets m1/oem filter. Nothing fancy but they are our transportation and our toys so ill
Pay the extra $20
 
YOU HAVE GOT TO BE KIDDING ME. based on the factual data provided to me here, for which I am grateful, and I decided to drain the 100 mile or so old super tech and save it for later. I put in quaker state, which one of you told me has more Molly if I remember correctly, and the vehicle is back to silent when cold.

I’ve had great luck with super tech over the years, I researched the crap out of it and even called and talked to one of their chemists at the factory that make it about six or seven years ago. But, I think I am going to avoid it going forward. This is only been an issue on smaller higher mileage motors, but let’s face it, I specialize in Toyota Prius, and as anyone will tell you who truly knows the vehicle, 2004 through 2009 models were the best made , so that means the vast majority of my specialty is a small motor and probably with higher miles… The 1nzfxe.

This was a strange lesson to learn. Thank you all for hanging in there with me
 
I don’t know it was a long time ago - but the specs compared well to higher end oils so I ran with it
 
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