Thicker oil equals more timing chain wear

Messages
182
Location
The Netherlands
Today i read something interesting in a dutch automotive magazine that is handed out to a lot of repair shops, they also discuss a lot of common engine problems and discuss and clarify things with the help of experts.

This topic was about sticking to oem oil spec or going to a different spec/weihgt. So one of our favorite subjects :)

One lubricant expert stated that you should stick to oem wheight/spec (which i agree with) because with switching to a thicker weight the oil pressure will increase which in terms will also put more force/pressure on the timing chain tensioner because those are motor oil hydraulicly actuated.

I thought this was an interesting point which probably has some truth to it: thicker oil= less internal leakage/flow = higher pressure = more force on tensioner = more tensioning/stretching force on the chainlinks and sprockets itself.

Especially when the oil is cold, and by using thicker cold grades then oem spec.


Some engines are known for having poor timingchain quality, other have no problems at all.
I guess that maybe the engines that are known for poor quality might wear a little faster, but i dont think it will cause a lot of trouble on the cars that dont have any problems with it generaly.
 
Messages
209
Location
South
Not all engines but traditional V8s built back in the day...
Crank turns camshaft via timing chain, cam has gear that operates distributor, distributor spins oil pump via a shaft. Thick oil makes more resistantance on the pump thus strains everything mentioned above.
Doubt that’s their point though.
 
Messages
649
Not all engines but traditional V8s built back in the day...
Crank turns camshaft via timing chain, cam has gear that operates distributor, distributor spins oil pump via a shaft. Thick oil makes more resistantance on the pump thus strains everything mentioned above.
Doubt that’s their point though.
I have heard of oil pump drives breaking in extreme cold with thick oil.

Not sure I can imagine going from a 20-30 weight having a negative effect on a timing chain tensioner though.
 
Messages
26,510
Location
PNW
If timing chains are stretching from the oil pressure on the tensioner, then they are very low quality chains. There is probably way more stress put on the chain from it's normal operation of turning the camshafts and shock loads due to RPM variations than what a tensioner would put on it. I highly doubt there is that much pressure on the chain tensions regardless of the oil viscosity. Did this magazine article have actual test data that proved it, or was it just a "theory" by some guy?

So does that mean timing chains stretch like crazy when the oil is cold and the oil pressure is maxed out (PD pump in pressure relief)? <sarcasm>
 
Messages
634
Location
United States
there’s a billion different ways you can make a timing chain setup. only thing they have in common is a crank sprocket that drives a chain and that drives the cam(s)

overall length, single/double/morse roller, type of guide material, tensioner design all play a factor.
 
Messages
15,598
Location
NE,Ohio
I think its total hogwash.

now do I think 20w50 is good idea in something that requires 5w20.. no.
but thicker oil is going to do nothing to the timing chain IMO.

for example take a car that specs multiple grades of oil.

run it on 5w40 in saudi arabia vs 5w20 in alaska..

Now I'm sure you might be able to think up a specific extreme circumstance where one or the other is a bad idea.
but for anyone using common sense.. its not an issue.
 
Messages
5,318
Location
Paramount, California
Today i read something interesting in a dutch automotive magazine that is handed out to a lot of repair shops, they also discuss a lot of common engine problems and discuss and clarify things with the help of experts.

This topic was about sticking to oem oil spec or going to a different spec/weihgt. So one of our favorite subjects :)

One lubricant expert stated that you should stick to oem wheight/spec (which i agree with) because with switching to a thicker weight the oil pressure will increase which in terms will also put more force/pressure on the timing chain tensioner because those are motor oil hydraulicly actuated.

I thought this was an interesting point which probably has some truth to it: thicker oil= less internal leakage/flow = higher pressure = more force on tensioner = more tensioning/stretching force on the chainlinks and sprockets itself.

Especially when the oil is cold, and by using thicker cold grades then oem spec.


Some engines are known for having poor timingchain quality, other have no problems at all.
I guess that maybe the engines that are known for poor quality might wear a little faster, but i dont think it will cause a lot of trouble on the cars that dont have any problems with it generaly.
What? No.

However, it is the base-oil viscosity, not the KV or HTHS viscosities that determine the timing chain wear. I have a table on this discussion board. The higher the base-oil viscosity, the less the valvetrain, timing chain, ring, and cylinder liner wear you will have.

Moreover, the additive package is crucial, as the dispersants that keep the abrasive particles in suspension and the AW/EP/FM additives that reduce the wear are also the key.
 
Messages
26,510
Location
PNW
^^^ OP was specifically talking about the force put on the tensioner(s) if a thicker oil is used, not about the oil that's actually lubricating the chain. But yeah, that's important too with respect to chain wear.
 
Messages
373
Location
Scottsdale, AZ
I’m sure that’s accurate if you go way way out of spec but how valid is “manufacturer oil spec” when fuel economy seems to be a huge component in selecting oil spec. Case in point our Rogue has a QR25DE with identical service and factory oil capacity as the QR25DE that is in the base model Frontier. The same identical engine, same oil capacity, one calls for 0w20 and the other 5w30.
 
Messages
9,124
Location
Virginia
I am going to ask the question...

Who on here as had a motor die because of a broken timing chain ??

I have actually...

On my ol 95 Nissan Sentra. Timing chain broke at 241,000+ miles. In the daggone Wendy's drive thru at that....

I got the car with 118,000 miles and changed the oil every 4,000 miles with Castrol Syntec 5w30.

I wonder what caused that timing chain to break ?

I have several theories... 1) the previous owner really did not keep up with changing the oil in that car... 2) And because of that the timing chain already had a lot of wear on it when I got it. 3) it is also possible that tiny abrasives cause the most issues with timing chains. Sizes smaller than 10 microns and maybe down to 5 or 6 microns or potentially even smaller than that. Therefore it makes air filter performance and oil filter performance key in maintaining timing chain condition. However long, long runs mean more and more extremely small abrasives are still in the oil even with a very good air filter using small dust testing per ISO 5011 and a very good oil filter with high efficiency ratings 99 percent at or less than 20 microns. Shortening a run is the best way to get rid of those very tiny abrasives that wear on timing chains.

I have cut my run interval on my car has it has gotten older and more miles on her. Now at 329,000 miles it still runs very, very good. I got the 08 Nissan Altima VQ with only 39,990 miles on it.
 
Messages
183
Location
Great Lakes
Just how much more pressure would be applied to the tensioner assy, with a 30W than with a 20W?
Not sure how much more pressure it would exert on the timing chain but I recently changed oil on a Silverado speccing 5w-30 that had PP in it and in went RGT same brand filter and same grade of oil it now consistently has 4psi higher reading with the RGT vs PP 🤷‍♂️
 

4WD

Messages
15,954
Location
Texas
Out of all the parameters that impact hydraulic pressure … viscosity is lower than most. Then you get into residual pressures in a dynamic state: how much difference from viscosity could the tiny area (P*A) in this tensioner get exposed to? And as already mentioned there is a PRV in the system and they tend to be right at the pump …

A cold reality with timing chains is that it’s not a “part” … it’s dozens of tiny parts only as good as it’s weakest link - a big QAQC exposure as these chains have become very long = cumulative effects of wear called stretch …
Some OEM’s have already upgraded chains … an indicator the first was a procurement issue.
 
Messages
16,643
Location
Upper Midwest
Not sure how much more pressure it would exert on the timing chain but I recently changed oil on a Silverado speccing 5w-30 that had PP in it and in went RGT same brand filter and same grade of oil it now consistently has 4psi higher reading with the RGT vs PP 🤷‍♂️
But not same brand. Grades are ranges so a different brand may have a slightly different viscosity.

How are you reliably measuring a 4 PSI difference?
 
Messages
15,720
Location
N.H, U.S.A.
I am going to ask the question...

Who on here as had a motor die because of a broken timing chain ??

I have actually...

On my ol 95 Nissan Sentra. Timing chain broke at 241,000+ miles. In the daggone Wendy's drive thru at that....

I got the car with 118,000 miles and changed the oil every 4,000 miles with Castrol Syntec 5w30.

I wonder what caused that timing chain to break ?

I have several theories... 1) the previous owner really did not keep up with changing the oil in that car...
I would say that it was because it was a '95 Sentra with 241K on it.
Not all Engines are 300K engines. These days it seems not many are even 90K engines with all the
"technological, power and fuel savings" inadequately tested advances.

I go back to a point I made and many poo-poo'ed when everything was going wet chain/vvti.

Dry Belt timing is better for OHC applications. You may not like the cost/hassle of changing the belt every 90-110K but you get a "new" timing system with every service.
Plus they sound better.
-Ken
 
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