Oil switch for GM 3.4L and 3.5L

[Hardware_Monk]

Thanks again for more background on these motors.

I've become aware that the newly introduced synthetic may be causing the engine to shed deposits. Its one reason I have tried several oils in short order in the Maxx, my most recent problem vehicle.

With this possibility in mind, and the upcoming cold weather, I believe I will immediately try the 0W-30 that was recommended by il_signore97 and seconded in principle by wolfc70. I have noticed other references to the 0W-30 and 0W-40 in the forum, but had no feel as to their usefulness.

If the 3.5 in the Maxx does not quiet down during hot operation, I will switch it to 0W-40.

I believe that if this oil type works for my Venture 3.4, the 0W-30 will be enough. It is noisier when cold, but quieter when warm, than the 3.5 in the Maxx. Apparently I'm also lucky that its not an oil burner...

I will check with a local dealer to see if they can find any record of a warranty repair on the 3.4 intake gaskets.

Meanwhile, once I find an oil to stick with, I'll have a UOA done for both engines. In the case of the 3.4, this could warn me of slow coolant leakage into the oil(?).

Had I known how different these newer engines would be, my approach would have been very different. I may never have made significant changes in oil type(as several earlier posts thought would have been wiser), or I would have done so in stages.

Once trouble started, I knew I needed to find an answer fast, so I am very grateful that so many helped sketch out where I was at.

Thank you all very much!

 

[addyguy]

A UOA would definetly show if coolant was getting into the oil - one of the main things that is checked with a UOA.

 

[il_signore97]

Originally Posted By: Hardware_Monk

Thank you all very much!





No problem. There is a lot of info on these forums. Use at your own risk!!! (j/k)

Give those oils a shot, and see how they work. Keep in mind that the noises (especially when hot) may take time to settle down. Hot lifter noise on pushrod motors due to partial blockage of their very small oil passage should pass, but slowly.

A UOA is an excellent way to find coolant in the oil before it becomes a huge issue. You will begin to see traces of Potassium, Sodium, and Silicon (due to dirt / broken seal injestion). You may also see higher than normal iron, lead, and copper in the 3.4L engine if it has been leaking for a while.

Keep us posted on your progress.

 

[GMBoy]

Originally Posted By: gizzsdad
I can't help but wonder if an additive was added before you bought them in order to quiet them down??


EXACTLY what I was thinking. I remember many (many!) years ago we used to put Wynn's Engine tuen-up in my friends 1981 Toyota Supra to quiet the lifters. Stuff worked for about 1-2k miles ....or until you changed the oil.

 

[fsskier]

Let me take an entirely different approach: Human sensation, including hearing is highly subjective, and results are very heavily influenced by expectations, other ambient noise, etc.

NVH (Noise, Vibration, Harshness) engineering science would probably recommend put in the correct oil (5W30?), turn up the radio and stop worrying!!

It seems that you can also tell gasoline quality while driving and even measure oil characteristics by "feeling it". Do a Google search on Ideomotor effect. Read the first several results carefully.... Note that you can be the first to win a MILLION DOLLARS if you can actually make a water witch work!!

We are all affected by this, but many are unaware of the huge influence this has on our perception.

 

[Hardware_Monk]

Automobiles are a bag of variables in a very expensive sack.

You can tell it what to do, but nothing says it will listen.

Most humans, however, do have a native capacity for hearing. I've spent enough decades in this field to understand the value of using it to listen.

Noise that appears where no noise was present is not a manufactured perception.

Similarly (to be at least a little unkind) if you aren't able to tell what is happening between your finger tips, perhaps a little time spent fondling dipsticks is in order. There is surely is large difference in fingerprint stiction between average used oil, and what's in your in-laws crankcase that hasn't been changed in "awhile". I certainly know which I'd rather have under load between the expensive iron and the bearing shells.

If you know what is normal in your own crankcase, you'll know when its different. Interpretations are up to you, but the information is there.

Ditto with gasoline. Fuel that races out the tailpipe is bad. Fuel that causes rough idling in a few tanks is bad. A fuel switch that produces spark knock is also bad. Fuel that does none of these things is good. Fuel that uses less pedal to do the same job is even better.

The senses provide us with information. Whether we use it is up to us.

I've seen people try to make power with money, by the numbers, and I've watched them trail behind us at any number of checkered flags. However, I've heard people boast that the only real way to set timing is "power tuning". I waited until they went away, and then got out my timing light and dwell meter.

I can air a tire by "ear" to within a pound, but believe me, if a gauge is available, I'll use it. When the gauge isn't where the gauge should be, and all that's around is unknown line pressure at a truckstop in Nowhere, USA, its nice to have a feel for things.

I don't have any interest in flame wars, fsskier. I'm just saying that a great deal can be learned by paying attention, with the radio off. When things are within normal parameters, I'll turn up the Jensen Triaxials - oh gosh, did I just date myself?

 

[Hardware_Monk]

As to progress, the Maxx 3.5 now has Mobil One 0W-30, as it was the only game in town, in that weight. For whatever it may matter, I notice that they prominently advertise on the bottle that it meets or exceeds 5W-30 and most 10W-30 oil spec's.

The developing noises that had me concerned have been reduced. I'll see what the trends are after the oil works in, and see whether 0W-40 may be called for, as a test, before winter weather makes it a bad idea. All this will certainly flush the system in the meantime...

If this were a choice between conventional oils, yeah, I might have tried EPA-spec stuff again right away, and hope to regain the old groove. Once the change to synthetic has been made, I understand that its unwise to switch back.

I want get the best choice made for this engine series, and then let it settle into a groove again. Whatever the tolerances and noises are at that point, its what it will live or die with. It was certainly clear that this engine group has different oil preferences than, say, the 4.3's and older 60 degree V6's. Thing is, they all say 5W-30 on their filler cap...

I once had to assemble a literal basket case 351W for a friend, adding a few performance parts. I could stick a 0.030 feeler gauge next to a piston or two at the top of their bores, but it ran quiet, and once pushed his 1980 F150 Econoline to an average 130mph for a timed flying mile. Speed was mainly limited by the huge air cushion under it... Point being, it surely wasn't perfect, but it was happy the way it was, and never did come apart.

Aaaanyway, at this point, the Maxx motor is moving in the right direction, by the sound of it. Time will tell more.

 

[il_signore97]

Good to hear. Hope the trend keeps up for you.

Just as an aside: Contrary to popular belief, you can switch back and forth to and from synthetic whenever you want. The only thing to keep in the back of your mind is that when switching a high mileage vehicle that has had an unknown history solely on dino oil to a good synthetic, there may be some cleaning, a bad seal can become exposed and begin to weep (if there actually is one that is bad), and you may not be able to take advantage of the really long extended oil change intervals that synthetic oil is known for, simply because of accumulated junk in the engine. This doesn't mean synthetic is the wrong way to go - just things to keep in mind.

 

[Hardware_Monk]

Mobil One 0W-30 still seems to be working well. Noise under light throttle acceleration seems to be nearly completely gone.

Using more pedal or loading on a hill will still generate noise, but not as loud.

Cold start noise is reduced considerably, and goes away quite quickly, now.

Fuel mileage has made a nice bonus improvement. 1.5-2mpg on the fuel economy readout, in spite of hills, headwinds, and a extra load in the tail.

I've yet to make an absolute mileage determination, but I'll take a relative improvement as a good sign, at this point.

 

[Hardware_Monk]

Mobil One 0W-30 lasted OK through some commuting time, plus a couple longer day trips with fairly heavy loads. Then mileage began to drop off, and it seemed to be dragging tail, like a car in need of an oil change.

Its possible it was still cleaning out deposits, and had done all it could for one change.

With temperature still moderate, Mobil 1 0W-40 was given a try. It was OK around 70 degrees, but by the time it dropped to 48, it wasn't working well at all.

Castrol 0w-30 seemed like an improvement over M1 0W-40, until another drop in temperature to the low to mid-30's made startup noise, and hot idle noise return again.

 

[NHHEMI]

Hardware_Monk;

The 3.4L is notorious for cold start noise/clatter. I found that out when my 08 Equinox with the 3.4L developed it early on. I did some research and found it to be a fairly common probem. If you have a vehicle still under warranty( not YOU specifically - just a general YOU meaning anyone )and you go to the dealer about it they actually time how long it takes for it to go away and if it is less than the max time limit GM sets than they say normal and no problem( GM and other mfg's use that term as an excuse far too often IMO ).

I also found out that my 08 3.4L was extremely picky about what oil fiilter I used. It wanted AC Delco filters. Every aftermarket brand I tried( Napa/Wix, STP, Bosch )resulted in a greater increase in cold start noise vs the OE filter. Going back to the AC filter dropped it to the lowest level.

I never had any noise from it when warmed up however. All cold start. I also ran synthetic oil. 5W-30 QS HP. I ran one OC of Castrol GTX( when I dumped the FF at 900 miles until I went to the QS at 5K )and it was pretty noisey. The synthetic quieted it down some and then when I went back to the AC filter it was as quiet as I could get it.

My Sister has a 2006 Impala with the 3.5L and it is a very good motor. No abnoraml cold or hot noises. That has been run on QS HP 5W-30 as well( recently changed - not happy with the cleaning ability of it in this engine - see the QS HP thread for more details ). Filters were Napa/Wix, STP, and AC.

The one thing I would say you have eben doing wrong is using all these different weights. Use the recommended 5W-30( or 0W-30 in winter ). These engines are not spec'd for all these other thicker weights. Use the correct weight. Also, there is absolutely NO harm in going back to dino from synthetic. That is a myth. You can swap back and forth and even mix them with no harm.

The only concern with dino to synthetic swaps is the very 1st time going synthetic if the engine has a ton of miles and was not cared for properly. The detergents in synthetic will dissolve any build up which can lead to increased oil consumption and/or leaks AND also can lead to an increase in engine noise! Those engines could have had a lot of crud inside that was keeping tolerances tight and insulating the noise. Now that it has been dissolved you have a sloppy motor and you can hear it.

You also have 3 options available to you that may help with these noise issues by freeing up stuck rings, lifters, valves, etc... that may be behind the noise. They are all a good choice for that and to clean the engines out fully as well.

1 - Seafoam
2 - Marvel Mystery Oil
3 - AutoRx

There is info on how to use them on the packaging they come in( can/bottle )and also in the oil additive section on this site so I won't go into it. Just to say they may help. I personally would try the Seafoam. I have used it in situations like yours and unless the noise was due to a failed part it actually helped a LOT and usually gets rid of the noise fully.

http://www.seafoamsales.com/motor-treatment/index.html

Good luck.

 

[ls1mike]

I have an 07 Equinox with 40,000 miles on it. It makes some noise when cold, but goes away. I have run M1 10W30 with an AC/Delco in it since day 1. We had on 05 that we put 120,000 miles on. All I ever did was change the oil and the brakes. The 05 was loud on startup too.

The 3.4 after 04 has a different intake and different gaskets too. If maintained properly they run for many trouble free miles.

My wife had a Toyota (I hated that car) before the first Equinox and that thing sounded like a diesel on start up but always ran fine. When stuff is cold it makes noise. Don't be hammering on it. You want noise? I will run out and start the Trans Am the next cold morning and tape it for you. Sounds like a Peterbuilt. Might be my Cam and valve springs though. Noise like someone already mentioned is very subjective and I know after I do some sort of maintenance "Something always sounds louder". Changes are it was there before and I just wasn't paying attention.

Now my question is this. If the car has 175,000 miles on it why screw with whatever oil it was running fine on before?

175,000 miles? Just drive the dang thing and go back to the original dino oil. Treat it like it is geriatric. It dosen't like things changed up.

 

[ls1mike]

Originally Posted By: Hardware_Monk
I've seen people try to make power with money, by the numbers, and I've watched them trail behind us at any number of checkered flags. However, I've heard people boast that the only real way to set timing is "power tuning". I waited until they went away, and then got out my timing light and dwell meter.


What the h*ll is that?

I hook up my lap top to do that sort of stuff.

 

[eljefino]

Do you still have the beauty covers on the engines? They have foam noise insulation on the undersides; GM knows how rattly they are when cold.

I'm talking about the plastic whatsamajigger that's held down by the oil filler. Sometimes they get lost/chucked.

 

[Hardware_Monk]

Both of these vehicles are the first vehicles I've owned or maintained, of this generation of engine.

The '92, '97, and 2003 4.3's I most recently worked on, followed all the old rules about what oil types, weights, etc, to use, and when. Cleaner was always better, and heavier was always a help on higher mile engines.

The 3.4 and 3.5 are apparently different internally, in some critical area. They have (apparently) been designed to actually require the use 5W-30 weight oil for more than just making EPA mileage ratings.

I'm afraid in both cases that I've been concluding the same thing as NHHEMI:

"Those engines could have had a lot of crud inside that was keeping tolerances tight and insulating the noise. Now that it has been dissolved you have a sloppy motor and you can hear it."

If I had known what would happen, no, I wouldn't have made a change in whatever maintenance had been keeping them quiet. The importance of retaining mileage-related crud build-up isn't something I have ever experienced.

As to the question of whether it really is making noise, the answer is loud and clear, out in my driveway.

When we looked at these, prior to purchase, both were very quiet. I did what I always do when judging a GM 60 degree V-6, I listened for startup noise from the outside, at the wheel well. I made sure the vehicle was dead cold, I waited til it was quiet around me, and then had my wife reach in and start the vehicle.

Even with snow on the ground, the 3.4 had only a very little light piston murmur, that went away in 30 seconds. For a 157,000 mile company maintained vehicle, I thought that was a real stroke of luck, considering the reputation of the motor.

Now, from inside or outside, it sounds like the usual box of rocks on startup that so many abused 60 degree V-6's sound like. When it warms up, yes, its pretty much entirely quiet.

The 3.5 isn't as lucky that way. The 3.5 had 115,000 on it when we bought it, and was entirely silent on startup and test drive. Now, when an oil switch is making noise on cold start, it also makes hot idle noise, and under load, a piston slap around 2400 RPM. When the oil is right for the outside temp, it does none of those things.

So far, the Mobil 1 0W-30 was the best (initially), so I haven't tried going back to 5W-30 yet.

The reduction in anti-wear components in consumer oils (about a year and a half ago?) made me want to use a synthetic if I could find the right one. But, I may need to try a return to dino, if nothing pans out in synthetic.

Oh, yeah - filters. I have been using Purolator Pure One filters for the most part, as it was the most commonly recommended filter in the forum, here.

I've begun to see examples of people claiming filter preferences, as was also noted by NHHEMI above. I've not tried changing filter brands yet.

 

[Hardware_Monk]

Short additional note, as in what to do next:

I've heard people on this forum state that Castrol Edge 5w-30 is "thinner" than the German Castrol 0W-30 I have in it now, but I'm not sure how or why that would be true.

If that is somehow the case, it might be worth a try, before leaving synthetic and going back to dino. I like its claim to have alot of anti-wear additives.

Giving 5W-30 dino a try should surely be cheap enough, but I thought I'd give synthetic one more shot, if there was a good candidate.

I've never liked using QS products, but I know that dates back to the days (1970's) when their 10w-30 was the quickest route to engine sludge buildup.

I think an AC filter might be worth trying, I've never had reason to fault them.

I did find this list, also:

http://www.gm.com/corporate/responsibility/environment/maintenance/gm_approved_engine_oils.pdf

 

[el_zorro]

Try GC or AMSOIL for a good cleanup, I wouldnt recommend solvent based additives and this may void your GM warranty as the manual clearly states that additives are not recommended for these engines.

 

[NHHEMI]

Originally Posted By: el_zorro
Try GC or AMSOIL for a good cleanup, I wouldnt recommend solvent based additives and this may void your GM warranty as the manual clearly states that additives are not recommended for these engines.


I doubt he has any warranty on these. Bought used as ex fleet vehicles with a ton of miles. Older vehicles as well.

 

[NHHEMI]

Originally Posted By: Hardware_Monk
Short additional note, as in what to do next:

I've heard people on this forum state that Castrol Edge 5w-30 is "thinner" than the German Castrol 0W-30 I have in it now, but I'm not sure how or why that would be true.

If that is somehow the case, it might be worth a try, before leaving synthetic and going back to dino. I like its claim to have alot of anti-wear additives.

Giving 5W-30 dino a try should surely be cheap enough, but I thought I'd give synthetic one more shot, if there was a good candidate.

I've never liked using QS products, but I know that dates back to the days (1970's) when their 10w-30 was the quickest route to engine sludge buildup.

I think an AC filter might be worth trying, I've never had reason to fault them.

I did find this list, also:

http://www.gm.com/corporate/responsibility/environment/maintenance/gm_approved_engine_oils.pdf


That list really is nothing more than a list of certified oils. Oils on that list are not better than oils not on it. In other words the oil mfg paid GM for the privelage of getting their oil tested and listed. All it means is the oil is actually certified to meet that standard. Doesn't make it better than a non certified oil.

Your engines call for the GM6094M standard and I doubt there is a synthetic oil out there that can not meet that( it is all about cold flow of the oil ). The other standard, GM4718M, is about heat resistance. Not an issue for you.

I would avoid the QS synthetic at least in your 3.5L. I had a bad experience with it in my Sisters Impala with the 3.5L( deposits and varnish with just 24K and 5K OCI's ). I actually did run it though( Horsepower )in my 08 3.4L Equinox and it seemed to do well but I didn't keep it very long( 11 months and 10K )to know if it was performing poorly in that too. I was very disappointed in the QS HP in her 3.5L. I have been a QS guy for a long time and I was really not impressed. I swapped her car over to Kendal GT1 synthetic.

I would give Penzoil Platinum a try or the Kendal GT1 if you want to try soemthing else. Both offer a 5W-30. PP offers a 0W-30 if you can find it.

 

[bubbatime]

Beater cars with unknown maintenance history. Sounds like a perfect candidate for ANY dino 5w30 or 10w30. Synthetics are just silly in this case. I'd use the cheapest oil on sale and drive the cars till the wheels fell off, but that is just me. I'd be more worried about the original (probably) transmission fluid with 175K miles on it.