Ok, so the googles are giving me all sorts of answers, so I thought I’d check with you guys.
'01 Camry V6 with 118k miles, never had a leak since we got it at 40k miles about 5-6 years ago. The last time I changed the oil, I used synthetic for the first time, and now I seem to have several small leaks around the gasket (smells wonderful…). I’ve read a couple places that switching to synthetic after nearly 120k miles may cause that. Thoughts? If it is from using synthetic, will switching back help, or is the damage done?
Back when that car was new the conventional wisdom at the time is exactly as you say: run synthetic early on, or never, because the old seals will leak due to the slipperier oil. I always thought it was bunk, but I know there are tons of anecdotes out here that say it’s so.
So, I guess my question is:
Why did you switch to synthetic now?
Maybe plugging along with conventional is fine.
Unless there is a good reason, and/or synthetic is specified by your manufacturer, I recommend not using it. Make sure the oil you use AT LEAST meets the requirements specified by the manufacturer, but synthetic is largely unnecessary. There are exceptions. But I your Toyota does not trigger any to my recollection.
To add to this, old cars tend to develop oil leaks. I’m sure there is a correlation between age of gaskets and tendency of failure. I’m not sure if the oil was the issue or just age. Now fuel leaks and failing fuel hoses due to ethanol in the gas I believe has been proven.
Honestly, I saw 5W30 and the price and assumed it wasn’t synthetic Got it home before I realized it and decided to try it out. Oh well Here’s hoping swapping back will at least help a little
That’s bunk. Synthetic oil doesn’t cause leaks, old engines cause leaks.
More importantly, forget about all labels except the one that matters: the list of manufacturer specifications that a given oil meets. If it matches your car’s recommended spec, use it. If it doesn’t, don’t put it in your engine. And if your engine leaks oil, replace the worn out seal; don’t blame it on your oil.
You have a few seals / gaskets that have outlived their service life and this oil change brought that to the surface in that oil burning off the exhaust smell…
A valve cover gasket set with tube seals & plenum gasket is about less than $40 not too difficult to tackle.
The question is …do you know when the timing belt was replaced?
Yeah, I know it’s on the list… from videos I’ve seen, it’s not the expense, it’s typically a decent amount of disassembly to get to them that I’ve never done. Only intimidated as it’s our one car that can hold a car seat, and my wife’s due date is tomorrow
We got the car at 40k mi, and I think I replaced the timing belt around 90k… but I wouldn’t put money on that. I may be remembering one of the other family/friend vehicles I’ve done that on.
I know this may be a long shot. But when my mechanic changed the timing belt, he put a sticker with the mileage and date on it on the firewall of my car. I thought that was really cool.
I didn’t notice it for about 6 months (white sticker on white paint). Maybe yours did to.
Yeah, but for OHC applications, your guides and tensioners have to be able to hold up to that mileage. And things can get messy, including damaging particulate load when the guides fail and the chain starts eating the cover.
Leave it long enough, and you will be replacing every bearing and refinishing every journal. And eating the precision finish on the oil pump as well. Leave it much longer, and you will be replacing the block.
Timing belts have a maintenance schedule. Chain tensioners and guides don’t. And if you have an engine prone to VCT phasor noise, you always wonder exactly which way any odd noise is getting ready to hit your pocketbook. The good news is that when you accept that 5W-20 is really the right oil, and that the appropriate motorcraft high flow filter really is the right answer, your Ford modular V8 is a much happier and quiet camper. The only “alarming” noise currently coming from my '05 5.4 engine compartment is a worn compressor that sounds a lot like phasor or chain noises can. I wind up occasionally turning off the AC to listen for peace of mind. I just worry about not hearing the real warning signs as a result.
Now the 4.6 (oddly an '01 also, and running synthetic) doesn’t seem to like to build oil pressure when cold at idle. I’m guessing that it also being a modular V8 is prone to early oil pump failures like the 5.4, and requires pulling the pan, valve covers and timing cover to get to the pump that is concentric around the front of the crankshaft.
Pretty much a true statement for any mechanical part. Most engines now have redesigned timing chain tensioners and replacement parts for older models that address the wear issue. But if you know something is an issue and don’t address it, like not replacing a timing belt until it breaks or strips, “leave it long enough” rule applies.
This is just me personally, if it is an interference fit engine, I’d prefer a chain over a belt. I’ve had a timing belt fail 15K before it’s recommended replacement time, if it had been an interference engine, basically the engine is rebuilt by the time you tear it apart to get at things that need replacing.
Still going yes, strong…
Chains are not the item that fail - they do get the blame tho. The guides usually wear beyond the their service life and break then a nanosecond or two later the chain fails. Some engines as Kevin mentioned - experience less than desirable consequences of a worn out chain and related parts - 4 cyl nissans would cut a trough into the head and valve cover(just amazing what a little oil on a loose dull chain can do).
Simple relatively straight chain configurations tend to have less wear - pretty obvious there. Then there are the “myths” of the days of yore…they are myths for a reason. Just ask any (for example) GM V8 pushrod engines in the “old days” where GM’s brilliant engineers opted for a plastic tooth on their timing chain gears only to have them shear off and into the oil pan close to 100k. Removing the pan on an Olds front wheel drive 455 cid(7.5Litres for this generation) V8 is no picnic.
Cars are cars - they all have their features and characteristics
Chain stretch is a thing, but the results are usually less catastrophic than timing belt failure. Not much less annoying though. Typically, as you said, you see chain guide failure on chain-timed OHC engines, but in a well-designed system, the results aren’t catastrophic, just noisy. See Nissan engines in the 90s. KA and SR timing chain guides make a lot of noise when they die, but the separate tensioner is much stouter and tends to last the life of the vehicle, which usually isn’t limited by engine longevity.
But then, everything has a service life, and belt or chain you’re best staying within it. And not blaming your oil.
My OLDs 84 Delta 88 had chain stretch. The camshaft sprocket was die cast. Ironically I switched oil brands the night before, not that it caused the stretch. I still have it sitting on my wall in my garage.
Here’s hoping swapping back will at least help a little