Sugar Bears 2015 GMC Terrain SLE-2 2.4 AWD

Grumpy Bear · July 25, 2022

7/25/2022

UOA Sent

Grumpy Bear · July 29, 2022

Synthetic Advantage Lab Results for Unit 581

7/28/2022

178,800 Miles

This was a tuner sample. No physicals this time.

Oil Castrol 5W40 Euro

Fuels Dilution 0.2% by GC (This had been running 5% to 8% and killing viscosity)

KF water 357 ppm. A huge reduction

Huston we have a winner. Fuel dilution issue now solved.

Oxidation 11

Nitration 10

Antiwear 15

Sulfation 17

Glycol 0

Soot 0

Combustion is really REALLY REALLY good!

Time to work on oil control. She's used a quart in these last 2K miles. Varnish again no doubt about that.

I'm very hopeful however, now than I will not be spitting into the wind anymore. Time for some house cleaning.

Grumpy Bear · July 29, 2022

179,141 Services

7/29/2022

2408.5 miles this OCI with a quart of makeup

Dropped a pint of Kano Kreen in the oil and drove is 228 miles round trip down state the dropped it hot and long

Cut the filter open. Chunks of carbon. Like a mechanical pencil lead all broke up but not metal. Media loaded up.

5.25 Quarts Red Line HP 5W30 and right on the full mark hot after 15 minutes drain down. Freed up some room it seems.

FRAM XG9018

Pint of Red Line SI-1 in the tank of E-20.

Note on the cleaning. About 25 miles into the run the oil cooled down about 8 degrees. Ran it to red line a few times. Went over 200 then pulled back with I let up nicely. Trip clocked 32.5 mpg all Interstate at 55 mph except the whipping session.

Grumpy Bear · July 31, 2022

Lessons Learned

It's a long list and may take more than one post to remember and cover them all.

Lesson #1

I was told by several (meaning all consulted) sources that the HPFP was not the likely issue give the amount of fuel present in the system. I even internally questioned the results of the test and at times the lab questioned my sampling methods.

If you've followed this blow by blow and saw all six samples and the corresponding results then you know that this was not a single issue but a plethora of issues of which none seemed severe enough to cause the damage that was being caused. In addition a few mistakes made that spoiled progress. But in the end the lions share was indeed the fuel pump.

In the all of this particular lesson I concluded more than one lesson.

1.) The 'nose' is a very poor fuel indicator. I was unable to detect by smell anything under 6%.

2.) Assuming a single source is a mistake.

3.) Lab results don't always pass your 'gut check' and will defy your experience. Trust them anyway. A CG/IR can't lie.

This one fooled everyone but the lab data!

Yes, in the end the HPFP was the bulk of the issue even though it passed leak down test. 4.8% of it in matter of fact but there was an additional 1.5% (6.5% the first reading) that was combustion efficiency and stuck ring blow by. I even managed to induce a 3% addition manipulating the EVAP system setting me back a month.

Truth is IF the pump would have been done first and the result went below 2% I may have quit running this down so being wrong in this case turned out to be a blessing.

Lastly and most obviously the labs told us we had an issue and the area the issues were associated with BUT the lab data can not tell you specifically which parts is/are contributing to the total. You still have to do the diagnosis.

Grumpy Bear · August 1, 2022

179,673 Miles

8/1/2022

Yesterday we did a total interior detail and a nice under hood cleaning but not detailing. While doing the door jabs a sheet of paint came off the right rear door near the drains which required an spot repair of RUSTOLEUM white. This sort of thing is sort of common to the plain white GM uses. Seems a paint/primer/clear one step with little to no prep. Today it gets an exterior wash.

Lesson #2

Now on the third tank of fuel since the pump replacement and the improvement in mpg it stunning. Previous OCI result was 29.6 mpg. Now it is a bit over 32 mpg! Last OCI was a hair over 1,600 miles which means it burnt roughly 54 gallons of fuel and over those same miles at current efficiency that would be 50 gallons. 1600 miles at 40 mph average is 40 hours driving and 4 gallons / 40 hours is 0.1 gph leakage. Sounds huge until you break it down to a rate which is why I did so. I'd a got a BULL if I just said 4 gallons per 1600 miles, right?

This is a 5 quart system and the residual fuel was 5%. That is 8 ounces of gasoline remaining in the oil at OCI end. Meaning 98% of the fuel that leaked into the system evaporated and was sent via the CCV back to the intake attempting to leave behind all the varnish nearly 4 gallons of fuel can generate. The tail pipe will attest to the rich/oil residuals condition And it did this for as many oil changes as an untold number of miles could produce. No wonder the oil control rings can't keep up.

This was a reason for the very short oil changes while we ran this issue down. Oil can only hold so much crap but even cheap oil, changed often enough, will keep her internally healthy till such situations can be diagnosed and attended to.

Using a much better oil WHILE she suffered may have reduced consumption by a fraction via a better ring seal but the dilution rate effect on viscosity made that impractical and expensive. Band-Aid on a GSW.

I thought the COSTCO Signature 5W40 and SuperTech Full SYn 5W40 that were the backbone of this ordeal did a wonderful job of keeping her ticking while taking her licking as can be seen by the wear metals.

While it is true that short OCI's HIDE problems:

they can also be a temporary solution while you run a unknown down.

customboss · August 1, 2022

25 minutes ago, Grumpy Bear said:

179,673 Miles

8/1/2022

Yesterday we did a total interior detail and a nice under hood cleaning but not detailing. While doing the door jabs a sheet of paint came off the right rear door near the drains which required an spot repair of RUSTOLEUM white. This sort of thing is sort of common to the plain white GM uses. Seems a paint/primer/clear one step with little to no prep. Today it gets an exterior wash.

Lesson #2

Now on the third tank of fuel since the pump replacement and the improvement in mpg it stunning. Previous OCI result was 29.6 mpg. Now it is a bit over 32 mpg! Last OCI was a hair over 1,600 miles which means it burnt roughly 54 gallons of fuel and over those same miles at current efficiency that would be 50 gallons. 1600 miles at 40 mph average is 40 hours driving and 4 gallons / 40 hours is 0.1 gph leakage. Sounds huge until you break it down to a rate which is why I did so. I'd a got a BULL if I just said 4 gallons per 1600 miles, right?

This is a 5 quart system and the residual fuel was 5%. That is 8 ounces of gasoline remaining in the oil at OCI end. Meaning 98% of the fuel that leaked into the system evaporated and was sent via the CCV back to the intake attempting to leave behind all the varnish nearly 4 gallons of fuel can generate. The tail pipe will attest to the rich/oil residuals condition And it did this for as many oil changes as an untold number of miles could produce. No wonder the oil control rings can't keep up.

This was a reason for the very short oil changes while we ran this issue down. Oil can only hold so much crap but even cheap oil, changed often enough, will keep her internally healthy till such situations can be diagnosed and attended to.

Using a much better oil WHILE she suffered may have reduced consumption by a fraction via a better ring seal but the dilution rate effect on viscosity made that impractical and expensive. Band-Aid on a GSW.

I thought the COSTCO Signature 5W40 and SuperTech Full SYn 5W40 that were the backbone of this ordeal did a wonderful job of keeping her ticking while taking her licking as can be seen by the wear metals.

While it is true that short OCI's HIDE problems:

they can also be a temporary solution while you run a unknown down.

Great overview with one minor observation I'm gonna push back on that a bit.

Petroleum engine oils GRP II and III bases have almost 0 solvency. Even GRP I can clean for a bit. Not gonna see GRP I anymore in any formula for the most part.

Once the more solvent additives give up in a high fuels dilute issue that gasoline residual you describe above will shellac and DI varnishes internals as we see here.

A GRP IV or advanced bio GRP III++( near GRP IV but with more solvency than PAO ) cut from an estolide like we see in the higher end Amsoil, Redline, NEO, Royal Purple, Renewable Lubricants, BioSynthetic, Evolve, even Havoline Pro RS ( a near 30% cut of estolides) will solve out or hinder the fuel carbons sticking.

As an aside when using a high level oil analysis that is interpreted properly everyone needs to remember unless the analyst is sitting on your shoulder while troubleshooting that analyst is looking at numbers on a page to tell you the area that needs addressed. Why a solid Tech or Mech is needed to hear the results, then use exceptional troubleshooting skills to find the cause. The oil analysis is very good at isolating the cause to a degree. If you have multiple variable causes you systematically iron them out.

Most here were ready for you to get a new short block or trade it in and start over. In the next 100,000 miles you have a wonderful SUV that will pay you back in MPG gains and hopefully a very low oil consumption rate.

Chemistry can produce better living.....

Grumpy Bear · August 2, 2022

11 hours ago, customboss said:

Most here were ready for you to get a new short block or trade it in and start over.

Yea...about that...

Push back on the push back :crackup:

Group III, III+ GTL and PAO's are horrible solvents. Esters however in all there forms are very good solvents.

https://www.machinerylubrication.com/Read/31106/polyalphaolefin-pao-lubricants

Polyalphaolefin History and Facts

Developed in the 1930s; first commercial engine oils in 1970s
Made from ethylene gas; still crude oil/natural gas dependent
Higher temperature resistance than mineral oil
- PAO up to approximately 160°C (320°F) continuous service; 270°C (520°F) intermittent
No wax content, therefore best low temperature of all synthetics (approximately minus 50°C to minus 60°C or minus 70°F)
Higher VI (approximately 130 to 140) than mineral oil (nearly 100)
Less volatile than mineral oil (higher flash point, less flammable, lower hydrocarbon emissions)
Lower natural lubricity than mineral oil
- Polyalphaolefin base oil not necessarily less wear than mineral base oil (additive-dependent property)
Compatible with mineral oil
Problems – very non-polar (low natural solvency, additive solubility, lower lubricity and film strength)
Forms hard deposits in reciprocating compressors
Must blend in 5 to 20 percent ester base oil for seal swell, additive solubility and lubricity
Not biodegradable

************************************

The above is also true of Group III, III+ and GTL.

Edited August 2, 2022 by Grumpy Bear

Grumpy Bear · August 2, 2022

180,045 Miles

8/1/2022

900 miles this OCI and still full. Oil is coloring rapidly. But not black. Amber tones. Tones of shellac. I expected this.

Dropped in the smaller CCV restrictor under the PCV valve. Considerably less traffic now.

Trip to Peoria today. 350 miles round trip mostly Interstate 32+ mpg. Windy. 32.38 mpg over the first 900 miles result.

Hoerr Racing for a Red Line run. Price increase coming so picked up a few cases of the HP Euro 5W30 low SAPS for Dizzy's use only. I can actually make this run and the cost of fuel is less than shipping. Well...and I like to drive.

Moving back to UNL88 for now. No cost savings now blending E20 and it's a pain. UNL88's largest supplier locally is Casey's and they gouge. I have one source of an unbranded at Petro that is nicely priced but not top tier. Considering reverting to E10 Top Tier.

customboss · August 2, 2022

10 hours ago, Grumpy Bear said:

180,045 Miles

8/1/2022

900 miles this OCI and still full. Oil is coloring rapidly. But not black. Amber tones. Tones of shellac. I expected this.

Dropped in the smaller CCV restrictor under the PCV valve. Considerably less traffic now.

Trip to Peoria today. 350 miles round trip mostly Interstate 32+ mpg. Windy. 32.38 mpg over the first 900 miles result.

Hoerr Racing for a Red Line run. Price increase coming so picked up a few cases of the HP Euro 5W30 low SAPS for Dizzy's use only. I can actually make this run and the cost of fuel is less than shipping. Well...and I like to drive.

Moving back to UNL88 for now. No cost savings now blending E20 and it's a pain. UNL88's largest supplier locally is Casey's and they gouge. I have one source of an unbranded at Petro that is nicely priced but not top tier. Considering reverting to E10 Top Tier.

Let us know how the E15 does. Its 86 octane here, using really crappy base gasoline......but its water out tailpipe and no carbon. 88 average octane probably a good mix for Dizzy.

customboss · August 2, 2022

10 hours ago, Grumpy Bear said:

Yea...about that...

Push back on the push back

Group III, III+ GTL and PAO's are horrible solvents. Esters however in all there forms are very good solvents.

https://www.machinerylubrication.com/Read/31106/polyalphaolefin-pao-lubricants

Polyalphaolefin History and Facts

Developed in the 1930s; first commercial engine oils in 1970s

Made from ethylene gas; still crude oil/natural gas dependent

Higher temperature resistance than mineral oil

PAO up to approximately 160°C (320°F) continuous service; 270°C (520°F) intermittent

No wax content, therefore best low temperature of all synthetics (approximately minus 50°C to minus 60°C or minus 70°F)

Higher VI (approximately 130 to 140) than mineral oil (nearly 100)

Less volatile than mineral oil (higher flash point, less flammable, lower hydrocarbon emissions)

Lower natural lubricity than mineral oil

Polyalphaolefin base oil not necessarily less wear than mineral base oil (additive-dependent property)

Compatible with mineral oil

Problems – very non-polar (low natural solvency, additive solubility, lower lubricity and film strength)

Forms hard deposits in reciprocating compressors

Must blend in 5 to 20 percent ester base oil for seal swell, additive solubility and lubricity

Not biodegradable

************************************

The above is also true of Group III, III+ and GTL.

Few are reading this but it's a good thread. LOL

Your quote from Machinery Lubrication is old news and was true overall about ~20 years ago......that PAO formulation is no longer a major player, why? Cost and new chemistries for GRP III++ ( estolides and other sugar based synthetics) can add all the solvency and miscibility you need at a VERY LOW treat and not reportable on any SDS. RLI does it with cold pressed, filtered veg bases. Then we have these which are being used in larger quantities now. Even ZDTP esters provide solvency, anti oxidation at low cost. Low deposit formation too.

2022 patent that is being used for base oils even before this particular patent.

https://www.sciencedirect.com/science/article/pii/S0022328X22000092

XOM metallocene PAO with AN is a consistent with XOM products. AN providing solvency. The VII and PPD has become some of their base.

BioSynthetic inc makes a lubricant with a majority base GRP II+ and a small cut of estolides with exceptional performance.

The reason you cant find the base oils in many of the boutique formulations like the Redline you prefer is they are not petroleum based synthetics. Redline Euro 5w30 is < 55% PAO from Chevron Phillips. Whats the rest unreported?

BTW I used to buy Oldsmobile racing stuff from Hoerr. Thats a long time ago.....

The Redline Euro 5w30 is gonna run really well in Dizzy.

garagerog · August 2, 2022

Grumpy, one can't help but admire your dogged determination to get to the bottom of the myriad of problems that the GDI 2.4 engine has, I just hope you don't get to feeling so good about resolving the engine issues only to get bit in the arse by the transfer case. I belong to a Terrain/Equinox forum and judging by the threads I see there, it appears that the transfer cases have an abnormally high failure rate, and surprise, surprise, GM is unable (or unwilling) to supply new, replacement transfer cases to their dealers. I looked up the curb weights of the AWD and FWD comparable models and was somewhat shocked that the AWD only weighs a little over 160 lbs more than the FWD. So we're not only talking about a transfer case, but a driveshaft, rear differential and axles and that only adds up to a 160 lbs? Makes me think that these are uber light duty components more suited for a side by side ATV than a 4000 lb crossover.

Grumpy Bear · August 2, 2022

4 hours ago, customboss said:

Redline Euro 5w30 is < 55% PAO from Chevron Phillips. Whats the rest unreported?

NPG Polyol Ester

Grumpy Bear · August 2, 2022

3 hours ago, garagerog said:

GM is unable (or unwilling) to supply new, replacement transfer cases to their dealers.

You mean this part?

https://www.gmpartsonline.net/oem-parts/gm-rear-wheel-drive-differential-carrier-housing-42540531?c=Zz11bml2ZXJzYWxzLWFuZC1yZWFyLWF4bGUmcz1kaWZmZXJlbnRpYWwmbD03Jm49QXNzZW1ibGllcyBQYWdlJmE9Z21jJm89dGVycmFpbiZ5PTIwMTUmdD1kZW5hbGkmZT0zLTZsLXY2LWdhcw%3D%3D

mikef95 · August 2, 2022

So to clarify, are you saying that a bad high pressure fuel pump was the primary cause of your oil consumption?

Mine doesn't actually appear to be consuming oil over the last 3k miles, but we're doing an oil change next week and will confirm at that time. We had a shop do the last one and I'm thinking they didn't actually change the oil...

If the HPFP is the issue, and mine is consuming oil, I'll go ahead and get that changed asap.

Grumpy Bear · August 2, 2022

6 minutes ago, mikef95 said:

So to clarify, are you saying that a bad high pressure fuel pump was the primary cause of your oil consumption?

Mine doesn't actually appear to be consuming oil over the last 3k miles, but we're doing an oil change next week and will confirm at that time. We had a shop do the last one and I'm thinking they didn't actually change the oil...

If the HPFP is the issue, and mine is consuming oil, I'll go ahead and get that changed asap.

Short answer? Yes.

I would run a sample however before tossing several hundred dollars at it. There is more than one reason a motor will use oil, right? The sample will show if any is present and if so how much. Otherwise...you are flying blind