Sugar Bears 2015 GMC Terrain SLE-2 2.4 AWD

Grumpy Bear · June 12, 2023

Mileage on Last 9 Oil Changes

Results, not averages. Add up all the miles and gallons for an individual OCI, calculate and plot. A lot less noise in the data this way. Dizzy loves hot weather. With Mrs. Bear driving on the Interstate at 65 mph on a 200-mile trip it returned 28.14 mpg. Not quite 20K miles of data in this chart.

New chart in new post.

Edited June 19, 2023 by Grumpy Bear

Grumpy Bear · June 15, 2023

$6.65 for this? :mad: Missing one in the inner fender panel I suppose from last bulb change. Bandits!

Part # 11612035

BTW found these by part number at Rock Auto for 47 cents each.

Edited June 16, 2023 by Grumpy Bear

Ianf · June 16, 2023

Most body shops I use will give them to you for free. They get them for 2 to 3 cents in bulk.

Grumpy Bear · June 19, 2023

215,000 Mile Service

6/19/2023

1,258 miles this OCI

1 Quart High Performance Lubricants SAE40 EC

4 Quarts Shell Rotella T6 5W40

1 Purolator PL15436

43.716 Gallons over 1257 miles = 28.78 mpg result.

7.5 ounces oil usage measured on outage or a quart in 5,300 miles. 0.1329% on fuel.

Edited July 2, 2023 by Grumpy Bear

Grumpy Bear · June 20, 2023

Newer post has latest graph.

Edited July 12, 2023 by Grumpy Bear
Update

Grumpy Bear · June 30, 2023

216,250 Mile Service

6/30/2023

1,250 miles this OCI

1 Quart High Performance Lubricants SAE40 EC

4 Quarts Shell Rotella T6 5W40

No filter

39.209 Gallons over 1,128 miles = 28.77 mpg result.

6.94 ounces oil usage or a quart in 5,764 miles. 0.1259% on fuel.

Edited July 8, 2023 by Grumpy Bear

Grumpy Bear · July 3, 2023

Not Zero

Sometimes you're the windshield. Sometimes you're the bug. I've been the later a few weeks now. Brain of mud staring to long at spread sheet formulas. I've corrected the last three post. Not as good as I had thought but better than I hoped and a new method to find the end point.

The title says it all. Still making progress. Small progress but progress and it will end with this chart hitting zero in multiple back-to-back OCI's.

The chart is the product of several calculations, hence the error. For each oil change period I log all fuel and measure all oil. The oil is calculated as a percentage of the total fuel used for that period based on the result, not an average but not exact either. I can't fill on less than five gallons so inside the window, normally half that distance. That number is translated to the fuel that would have been consumed if precise and then measured oil is calculated as a percentage of that number.

From one OCI to the next the difference of the current is subtracted from the last and a running record kept and plotted in the graph above which is the improvement OCI over OCI. When that number falls to zero improvement has stalled. If it does so several times in a row. It's as good as it will ever get without a rebuild.

As these records are getting quite large, I write formulas to do the heavy lifting and on occasion I make an error in one cell or another. If the formula is in error in structure, I know right away. Excel will not allow imperfect equations to be written and accepted. That said it has no way to know when I error in input of a value and accepts that willingly. Huge errors are obvious in outputs. Small errors that stack might go awhile before I catch them. The need to accumulate to a size I will notice.

As fuel consumption has been improving as oil consumption declines a small error make take a while to compound to that point. Anyway, enough crow for now. I made a mistake, and I corrected it. I'll get over it.

Small but recoverable issue is that I lost one data points exact value and averaging leaves the chart with three points identical in weighting. But still positive values so still improving point over point. It's like looking away from the road for a second and loosing how you got to the point you are now but certain you are in a new location. Some things matter more than others. This is one that does not, but I mention it for the record.

It's an ill wind the blows that does not benefit the sails of some ship. This is no different. We passed the point where one would notice usage on the stick and as a result, I know with certainty that this motor does not and never did hold 5 quarts. Interestingly the book says "approximately' 5 quarts and the equivalent liter value. The 8-10 minute hot check still showed full even though it used just under 7 ounces the last OCI. Pretty handy for GM when you are doing consumption checks, right?

I also have an explanation for the illusion of not using any for a thousand miles and then using. Usage is quite linear. I suspected this quite some time ago as you will find back in the record times I added but 4.75 quarts to find full on the stick. The filter volume, which does not have an anti-drain back, confused me for some time.

So.... consumption has been cut in half to date and it is still improving. Values are the projection of the actual value.

Edited July 3, 2023 by Grumpy Bear

Grumpy Bear · July 4, 2023

Chit Chat

We made a loop yesterday down I-39S to I-88W to I-80E to I-74E to I-39N and home again. A bit over 300 miles and on a tank that already had over 200 of light mixed driving on it. Pace was 60 mph and it was hot, dry and nearly windless. Got a bit of a breeze late in the afternoon. The reward was 30.6 mpg measured. Oil temp ran right at 197-201 F and the transmission just under 170 F slight breeze to the back and 165 if to the front, spiking only for rest stop hot soak. But it recovered nicely. I tried 65 for a while and trans temps climbed. Slowed for a while to 55 and they drew back. Neither taking much effort to do so. Nothing unexpected but the mileage. Best 60 mph tank ever. 527 total miles on 17.215 gallons. Cutting it close.

This OCI has been made up of days like this so long hauls in hot weather with little humidity or wind and few stop/start situations. Next day or so as weather permits, I'll be changing oil again. Might be the quickest 1250 miles on this rig yet.

Now sitting at 1100 miles the oils appearance is much as I would have expected at say 500 miles. GDI motors are cold start over rich pigs :mad: .

Found some nice radio stations along the way to drown out the tire howl. :crackup: All four leave a print like this.

Edited July 6, 2023 by Grumpy Bear

Grumpy Bear · July 5, 2023

217,460 Mile Service

7/5/2023

1,210-mile OCI

17,460 miles into the cleaning.

I got 3.5 ounces more out of it than I put in it.

I'm calling it TBD for now. But charting it as 1.56 ounces or 0.03% of fuel.

Several possible reasons.

1.) I measured the outage while the oil was still warm. Expansion.

2.) Rain delay gave a longer drain time. About 30 minutes longer. 2 hours and change. Which would also mean I may have left a few ounces in it the last oil change? :dunno:

3.) HLP tends to overpour their drinks. Sometimes as much as 2 ounces.

4.) This could represent roughly 2% fuel dilution. We will test for that. It's been a while.

5.) Any combination of/or all of the above.

1332 miles, 44.791 gallons = 29.74 mpg. Better than expected. It's been hot, dry and windless.

4-quarts Shell Rotella T6 5W40 Full Synthetic

1-quart High Performance Lubricants SAE40-EC

No filter.

Reordered 12-quarts HPL SAE40-EC

UAO sent 7/7/2023 for sample pulled on 216,250-mile service.

Edited July 7, 2023 by Grumpy Bear

Grumpy Bear · July 11, 2023

7/11/2023 Operational Notes

In 2017 the EPA lowered the highway numbers from 32 to 31 mpg and city stayed the same at 22 and combine remained constant at 26 mpg. In a 400-mile loop today to dad's and back with 93 miles of mixed driving already on the clock the total tank resulted in a 30.8 mpg number. The return leg of that run at 33 mpg over 200 miles, gas ticket result not DIC number. Primary highway miles.

This chart is from the end of winter covering the cleaning cycle by total miles per OCI. Miles are more highway than city but still not all highway. Honest estimate would be between the 26 and 31 EPA cycle numbers. This chart includes the newest OCI done today. Posting later on that.

This has my attention as the oil is heavy. A blend of 5W40 and SAE 40, 4:1 in the motor instead of 5W30 and using Valvoline 80W140 in the AWD differential instead of 75W90. AC on most of the time. During the worst of her oil usage, she struggled to get low 30's at 45 mph with a tail wind and AC off. Now 60 mph into 10 mph headwinds? Progress.

Grumpy Bear · July 12, 2023

218,750 Mile Service

7/11/2023

1,290-mile OCI

3 ounces makeup oil

1,246 miles on 41.753 gallons = 29.84 mpg

2 pints HPL SAE40-EC

7 pints 6 ounces Shell Rotella T6 5W40

1 FRAM TG9018 filter.

A bit of drama. After running 540 miles makeup free I decided to check on the baffle which requires removing the CCV orifice plate. Got distracted and forgot to reinstall it and drove the hill and dale of Wisconsin Iowa County wherein it ate some oil in the next 250 miles. Put the baffle back in after adding make up and run 400 miles round trip to Cedar Rapids Iowa over hill and dale using a hint. So, nothing, gulp and then a trace. On measuring after the drop, it came to 3 ounces used over 1290 miles but nearly all of that in just 250 miles running on the PCV valve alone. I also noticed when reinstalling the orifice, I had left out the demister pad. Bain dead, I think. So that went back in as well for the last 500 miles where it used the 'trace' noting during the oil change the amount of oil above the orifice was greater with the demister than without.

At the oil change i cut a 2X larger pad and installed it UNDER the orifice plate and above the valve cover baffle plate. Something I have been hesitant to do fearing losing it in the rocker box. A mockup proved this could not happen. Then went and flogged it for a while. Inspected and??? Dry as a bone above the plate! First time that's actually happened.

Remember last OCI I guessed on the makeup as it was positive and so assigned it 1.56 ounces. A guess really. I've reassigned that to 3 ounces as well and recharted. So it looks like this now on percent of fuel:

And this on ounces per thousand miles normalized.

Okay, you may have noticed the unusual fill volume. I held out 10 ounces this OCI. This put the level on the stick down one diamond hot 15 minutes after HOT shutdown on the level. JUST under full. Halfway down the stick parked 3 degrees nose up in the drive. 8 ounces off 5 quarts is full. 5 quarts is over full. Between 'over full' and no demister in the valve cover it forces some usage. As each OCI has delivered less and less makeup required and now very close to really normal usage I'm picking the meat off the bone. Over full whips oil on to the cylinder walls. Bad. No demister pulls oil out of the crankcase and into the intake manifold. Also, bad.

This will be the last 1,250-mile OCI. The next two will be 1,500 and then 2,000 where I will stop and revaluate.

Point is progress is being made and it is good. I am now tossing better oil that most people use. It is amber, thick and slick on the stick at change time instead of the black thin and tacky as it had been. Mileage is more consistent and much higher, and the feel is remarkably improved.

Edited July 12, 2023 by Grumpy Bear

Grumpy Bear · July 14, 2023

Dizzy the Destroyer

Know that saying, "Be careful what you wish for"? I wished to see the results of all this work. I got that and something I did not want to see. Glycol in the oil. Notes come attached with this report and among other things, "You have an issue OR there is some weird chemistry in the cleaner. I shot a note off to HPL supplying results to see what they may have to say.

They said, "Get a pressure check, it isn't the chemistry". These are some nice people at HPL. Sort of exchanges I use to have with Red Line before Phillips took over and sealed everyone's mouth shut. Anyway...

Oxidation is higher than I would have expected for the blend and glycol will advance oxidation rapidly. Put a question mark there.

Nitration was flagged. In spec but top of "spec". This one always gives me pause as I don't buy into the absolute unit methodology. Some oils start that high. I use 10 points over background. This is just a matter of 'school'. Blend average on typical base blend would be about 6 and small change. I'd get a raised eyebrow about 16 units.

Antiwear is typical for the diesel package of the oil and was noted as such.

A similar note was attached to KF water but not checked as while elevated it is still inside bounds. I find this as normal as can be on an orifice CCV system and a boatload of Esters which a KF mistakes as water. A head fake. Orifice systems are NOT POSITIVE evacuation systems. They are partial positive. Crankcase sees positive pressure much of the time in the inches of water ballpark. I hate these systems, but they are used often in motors tuned to give lowest possible pumping losses.

Fuel dilution. 2.0% Not ideal. Not uncommon for GDI either and it's pig rich start fuel mapping.

I like to troubleshoot in the Horses, Zebras, Unicorn method. Most obvious first. Pressure check it is and hope it's the cleaner removing hidden previous contaminants. Not likely but one can hope. HPL brought this up as a possible IF it passes the pressure check. Water pump would be next most likely and the one I gravitate towards. If this is true then we will do more than the water pump. While it can be replaced without disturbing the timing cover it ain't fun and as we have 200K plus on the timing chain and tensioners and a weep at the cover seal I'll have it all done.

If it is a Zebra or a Unicorn, we, Mrs. Bear and I, will reevaluate. I tip toward a remanufactured Jasper long block and she toward a newer something other. Until then this vehicle is on limited distance duty. 50 miles max and until repaired or replaced I'll stay with the shorter oil changes. Jason is working stupid hours and I'm having trouble getting shop time these days. So it stays in rotation, just on 'desk duty'.

Edited July 14, 2023 by Grumpy Bear

diyer2 · July 14, 2023

Sorry to hear this, but I believe dumping it was brought up.

KARNUT · July 14, 2023

Bars leak worked for me for two years running. The worst that could happen is it doesn’t work and use a stronger sealer. If the engine is going to be replaced anyway it’s worth a shot. At least in my world anyway. Obviously it’s not enough for a visual. I’ve never seen water in my oil other than sludge at the beginning of the drain. Of course I don’t drive it many miles to town and back. I’m with your better half, replace the ride ultimately.

Grumpy Bear · July 14, 2023

If it turns out to be the water pump, I doubt I will toss her in lieu of a proper repair.

This isn't that hard for me. If I replace the entire driveline, it cost a fraction of anything new that would be equal to it. Then I get to look into a whole new abys. More unknows. Better the devil I know ......