High MIleage Oil application / SM question

[hominid7]

I've done some searching, but have yet to come up with an answer, so here is my rambling question...

I have a 2001 Mazda 626 with the Mazda KL 2.5 liter DOHC V6. It has a solid lifter pack, so no HLA's to worry about. However the valve train is somewhat noisey and seems to be particularly picky about what kind of oil i use.

So far somewhat 'beefy' 5w30's seem to work best. Havoline 5w30 was a favorite and kept the valve train area silent. Castrol GTX and Motorcraft are also pretty decent. However a switch to a 10w30 brings about much more valve train area noise for some unknown reason. I believe it may have to do with the friction gear, making noise as a result of a change in oil pressure, or perhaps a lack of oil, or too much oil pressure at idle. If that is the case, the noise is cosmetic and only serves to irritate me, but i still prefer a completely silent engine.

Now that Havoline has gone on a diet, i'm looking at experimenting with some of the "High Mileage" oils, as they are a good way to achieve a beefy 5w30. Would there be any problems with using a high mileage oil (Like Maxlife or GTX HM) in a 2001 car with only 54000 miles? Are these nothing more than "SL" rated oils with something extra for seal conditioning? and will SL rated oils perhaps be better for engines designed with them in mind regardless of mileage?

My question somewhat stems from my noticing the valve train noise much more in the past year, along with my using only SM rated oils, not the SL rated ones the car was born and lived it's childhood on. Of course it could be age, but other than the bothersome drone/light knock at idle when using some 10w30's, the engine is perfect inside and out.

Engine uses no oil, appears to have zero signs of sludge or even varnish, properly operating PCV, and runds great. The noise i hear is a very slight drone/knock that is cyclical in nature and occurs only at idle, usually when the engine is warm.

Another thought is that the beefy 5w30's the engine seems to like are actually thicker at operating temp, so perhaps ironically 10w30's are too thin? A beefy 5w30 being somewhat thicker at operating temps than some 5w30's.

Thus far I've found the following:

Quakerstate 10w30 = noise
Pennzoil 10w30 = no noise
Pennzoil 5w30 = no noise
Castrol GTX 10w30 = slight noise
Castrol GTX 5w30 = no noise
Motrocraft 10w30 = slight noise
Motorcraft 5w30 = no noise
Havoline (old) 10w30 = slight noise
Havoline (old) 5w30 = no noise

I've used both OEM and WIX filters and cant tell any difference regarding noise.

FYI, the car owners manual recommends 10w30 above -13*F and 5w30 below 98*F. However Ford issued a TSB on the same engine in the Probe calling for 5w30 year round regardless of outside temp. Mazda seems to be sticking with the orig specs, yet the mazda dealer only uses 5w30.

Ideas? I'm guessing most folks will recommend not worrying about using 5w30 through the hottest of summer temps in Texas?

 

[Blue99]

It's hard to imagine how the noise could be directly connected to 100C viscosity, specifically since a number of these 5W & 10W formulations are within .5 cSt of each other.

If you perceived less noise with the 5w30 grades you may wish to look at the role that VI improvers may be playing in reducing the mechanical noise or the amount of transmitted noise.

BTW, Molakule always claimed that polymeric viscosity improvers had good lubricating properties.

If Pennzoil 5w30 provided acceptable results in the past, try blending in a 1/2 or 1 quart of Pennzoil 10W-40 to add even more VI improvers to the mix & see what this does for the noise levels.

Note - Mixing Disclaimer: While no one on Bitog has ever lost an engine to a homebrew, I have no way to assure you that all the functions of the combined additive packages will carry forward to the new blend!

 

[BillionPa]

try some german castrol...

 

[hominid7]

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If Pennzoil 5w30 provided acceptable results in the past, try blending in a 1/2 or 1 quart of Pennzoil 10W-40 to add even more VI improvers to the mix & see what this does for the noise levels.

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That's a very interesting idea. I have been very perplexed as to why some oils seem to be associated with noise and others none.

One of the worst offenders has been QuakerState 10w30. Then again one of the quietest oils has been Pennzoil 10w30. They are different, but they are not THAT different.

I should also mention that this sound i'm trying to get rid of is somewhat faint. My 75 yr old father cant seem to hear it, but his hearing is less than perfect.

Right now with Castrol GTX 5w30 at idle i hear only the slight tick of the injectors. Previously with Quakerstate 10w30 i would hear the tick of the injectors and every few seconds hear a slight *knock knock knock*. I've repeated this several times with various oils and with various filters.

The Wix filter and the Supertech filter were both associated with noise when using 10w30's. The time i tried pennzoil 10w30 was with an OEM filter and i got no noise. I have not tried Pennzoil 10w30 with either a wix or supertech. I suppose filter flow rates could be doing something.

On the mazda626 board the consensus seems to be it is related to oil pressure changes in relation to the friction gear at idle, with this engine being overly particular as to ones oil choice.

I should also note that with OEM filter and Motorcraft 5w30 (what the dealer uses) there is no noise. ALl of Mazdas engine noise related TSB's start off with changing the oil to motorcraft 5w30 and an oem filter and then proceed if noise is still present.

 

[hominid7]

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try some german castrol...

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I have thought about that, but there is something in my DNA that prevents me from paying 6 dollars per quart of oil.

Having said that, changing my oil often to try to eliminate this noise i've probably spent more than that

 

[Merkava_4]

It seems like thicker oils are not working for you; that's why I'd recommend you trying some Maxlife 5w30. You can get a 5 quart bottle at Walmart for about $12.00

 

[hominid7]

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It seems like thicker oils are not working for you; that's why I'd recommend you trying some Maxlife 5w30. You can get a 5 quart bottle at Walmart for about $12.00

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I do rather like the new maxlife labels Valvoline came out with. They even say synthetic blend on it!

 

[Ramblin Fever]

Hominid7 - I can't tell you how EXACTLY your first post was an exact concern/theory I had about an engine that too was raised on SL oil; in fact, when it became obvious that Havoline went on a diet, it made me realize it *wasn't* in my head.

I have since switched this truck to Maxlife 10w30 regular/synthetic, and noise is completely non-existant.

 

[hominid7]

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Hominid7 - I can't tell you how EXACTLY your first post was an exact concern/theory I had about an engine that too was raised on SL oil; in fact, when it became obvious that Havoline went on a diet, it made me realize it *wasn't* in my head.

I have since switched this truck to Maxlife 10w30 regular/synthetic, and noise is completely non-existant.

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I've been hesitant to try the high-mileage oils for fear of my cat-convertor suddenly exploding, but the more i read the less of a fear that is.

When i bought the car, the SL or even earlier oils i used never gave me a problem. I used 5w30's and 10w30's from several makers with no problems. Then suddenly with the advent of SM my car suddenly became much more particular about what oil it got, and what viscosity.

My initial thought on high mileage oils was that they were all marketing, but the more i've read the more i think perhaps the oil companies, in addition to having a good marketing idea, were aware that some older designs may not be fully tested or have been built with oils that left certain friction reducers and other additives out.

I'm wondering if the hefty moly in the old Havoline, even in the (old version) SM, was allowing for slightly better lubrication in certain designs.

My engine, if anyone is interested, was first intrroduced in 1992 and was an engine designed in conjunctioin with suzuki, an apparent base design that was origionally worked on by porsche. A cut and paste of the blurb from wikipedia is below:

The 2.5 L (2497 cc) KL family uses an 84.5 mm bore and 74.2 mm stroke. It includes the Japan-only KL-ZE, which produced 199 hp (149 kW) and 165 ft.lbf (224 Nm). Another variant, the KL-DE (often incorrectly called the KL-03) was the worldwide version, with 164-170 hp in various applications.

Mazda introduced a key technology with these engines, known as the Variable Resonance Induction System (VRIS). A series of two butterfly valves coupled with electronically controlled actuators varied the volume and length of a resonant chamber attached to the intake manifold, producing 4 resonant frequencies. The valves actuate at particular engine frequencies (i.e. RPMs) to produce optimal torque/horsepower output at any given engine speed.

 

[Merkava_4]

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I've been hesitant to try the high-mileage oils for fear of my cat-convertor suddenly exploding, but the more i read the less of a fear that is.

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I think you're confusing high mileage oils with diesel oils which have the phosphorous zinc added to them. There's no danger to high mileage oils.

Valvoline Maxlife is the only High Mileage oil that is NOT thicker than regular oils. If you're looking for a thick High Mileage oil, you have to look at something like Castrol GTX High Mileage.

Maxlife is 22% pure PAO synthetic; the same stuff Royal Purple is made out of; and as an added bonus, they both suspiciously smell alike.

 

[hominid7]

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I think you're confusing high mileage oils with diesel oils which have the phosphorous zinc added to them. There's no danger to high mileage oils.

Valvoline Maxlife is the only High Mileage oil that is NOT thicker than regular oils. If you're looking for a thick High Mileage oil, you have to look at something like Castrol GTX High Mileage.

Maxlife is 22% pure PAO synthetic; the same stuff Royal Purple is made out of; and as an added bonus, they both suspiciously smell alike.

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Thanks for the info.... I was thinking that SM oils were introduced to help with emission control problems on newer cars, and that high mileage oils were introduced right around the same time. I may be mistaken though.

Maxlife does sound interesting, and for what you get the price seems decent...

 

[Rodbuckler]

As long as you are spending alot of money on various oils, you should try the Castrol Elixion 5w30 and do a used oil analysis for us. It should be short on neither robustness nor additive package.

http://www.castrol.com/liveassets/bp_int.../0-999/1854.pdf

 

[hominid7]

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As long as you are spending alot of money on various oils, you should try the Castrol Elixion 5w30 and do a used oil analysis for us. It should be short on neither robustness nor additive package.

http://www.castrol.com/liveassets/bp_int.../0-999/1854.pdf

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Looks nice, except for that rather high ash #. I did spend some time after work today at autozone looking at the various syntec bottles, including the GC. I might decide to try a batch just for fun, but i'm unsure of going GC 0w30 or Syntec 5w40.

 

[Rodbuckler]

Noisy valvetrain cold usually means oil too thick cold. Noisy valvetrain hot usually means oil too thin for the flow volume, so flow is lost to the bottom end. It is not an easy problem to fix at hot idle without making it noisy cold.

Since your engine top-end sound has changed over time, I would suspect wear is the culprit since you don't have hydraulic lifters or lash adjusters. I just suggested an oil that would reduce the wear over that of car oils, but there are many other oiling options as you know.

 

[Merkava_4]

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Since your engine top-end sound has changed over time, I would suspect wear is the culprit since you don't have hydraulic lifters or lash adjusters.

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He's right, with solid lifters, you're going to have to do a lash adjustment eventually.