L87 Recall - Oil Changed - Engine & Fuel Economy Issue

[Scarey]

In the bulk the dealership buys, the price between 20w and 40w is small. Any excuse to raise prices is the new normal.

 

[tom082551]

Hello All,

Just visited my local dealership and had my 22 XL checked for the recall and ended up with the new heavier weight oil and extended warranty.

I couldn't be more disappointed with the performance of the engine as it now feels sluggish to accelerate, fuel economy has dropped roughly 30% and there is no way this baby is still outputting 420 BHP on the 6.2L

Yes, I know the heavier weight oil creates more drag/friction on the motor. But the difference is noticeable and unacceptable IMO.

Anyone else get the oil change and experiencing this issue?

I have run OW40 in my vehicles forever. Way back in the day it was Castro GTX 50 weight. Lack of performance is NOT the heavier weight oil issue! Something else is wrong?

 

[PA-WOODCHUCK]

Hello All,

Just visited my local dealership and had my 22 XL checked for the recall and ended up with the new heavier weight oil and extended warranty.

I couldn't be more disappointed with the performance of the engine as it now feels sluggish to accelerate, fuel economy has dropped roughly 30% and there is no way this baby is still outputting 420 BHP on the 6.2L

Yes, I know the heavier weight oil creates more drag/friction on the motor. But the difference is noticeable and unacceptable IMO.

Anyone else get the oil change and experiencing this issue?

what was your MPG before and after?

 

[2016Dom]

I would not put it past GM to detune the ECM

 

[tom082551]

Always premium fuel 93 octane. To be honest I don’t have that large a data set to work with yet as it was very recent but I was averaging 15/18 and it’s been roughly down to 10/12.

I have 84,000 on my 2022 Tahoe High Country and have NEVER used anything but 87 octane regular. I also have recorded 24.2 mpg while driving to Tampa (150 miles) with cruise set at 72 mph. That’s using regular fuel as well. While city stop and go during the slow season, I average 14.5 mpg and I baby my ride!

 

[jfoj]

I did the oil (upgrade) change myself to the 0-40 mobile 1. I asked my dealer and seeing as my number was not in Q yet they agreed with me to do it. And they would owe me an oil change.
BUT here is the kicker... I had the shop take a sample of the oil and give me the used oil filter and I sent them to be tested. The facility told me there may be no shavings or particles in the filter as this is my 5th change in aprox 15000 miles. (I'm nuts for changing oil and filters.) WAIT HERE IT COMES.... there was 4.1% fuel in the oil. I actually commented the oil looked like water at the shop. When the testing facility saw this they called me and asked if this was a GMC 6.2? I asked why? And was explained they have seen this in others. When I confirmed I do not use the traffic light start stop and also always run the truck once started. I was told to contact the dealer ASAP. I did that and was told it could be normal. IMO that is BS. So the next oil change will also be tested.
Can you tell me what mileage / time they gave on the warranty. Too bad in Canada we don't have lemon laws.
As for the mileage can't tell but I will agree that in order to get it to "move" I have to put it in sport mode and that helps. But kills the mileage .
I wish someone could tell me how to force them to take the truck back..

@NELLY1947,

You mentioned you are in Canada. While I assume the Summer weather is warmer, I bet the Winter is rather cold.

Not sure your driving habits, but in 40F ambient outside temps it takes about 25 minutes of driving to get the oil up to temperature to even start to cook some of the fuel out of the oil. I try to only use by truck when I plan on driving at least 30+ minutes. Additionally I have a Range DFM and ASS disabler on my truck. Often my typical driving habit is if I start the vehicle it will run for 1 to 6 hours at a time.

Before you deal with dealer on fuel contamination in the oil, check the air filter, think about your typical driving habits also understand if you are just now changing oil that was in the vehicle from last Winter you could have had fuel contamination from the colder weather.

Also DO NOT start the engine an allow it to warm up, it takes almost 2X longer for the oil to warm up at idle than with driving. I know in the Winter it is nice to Remote Start the truck and get in warm seats and a warm cabin, but this KILLS the engine oil with fuel, DO NOT DO IT.

 

[jfoj]

I have not noticed the performance issues mentioned but am upset that the dealer said that oil changes in the future will be much more expensive because of the 40wt oil. GM should address this with their customers.

@Randy_S

Do what I do, use Pennzoil Ultra Platinum 0W40 which is derived from Natural Gas. It is a very pure oil. While no "DEXOS" approved, there are a few reasons. Understand that Pennzoil makes a number of "DEXOS" approved oils, but 0W40 does not have a big market in GM vehicles, Pennzoil does not want to waste the money getting the oil "DEXOS" approved and also pay a licensing fee per quart and the main reason they do not want to get "DEXOS" approval is they would be required to turn over the oil formulation to GM in the approval process. This is why many higher end oils lack certain manufactures approvals.

For "DEXOS" approval the oil needs to have a low Sodium level to combat LSPI (Low Speed Pre Ignition) and have other detergent ingredients in the place of Sodium. Additionally the oil is suppose to not sludge up or become acidic within the GM OCI. I do not worry about this because I change my oil in no more than 4000 mile increments or about 50% on the OLM. Pennzoil Ultra Platinum has a low Sodium additive package.

I think my oil changes which I do myself with the OE AC Delco filter and 9 quarts of 0W40 Pennzoil Ultra Platinum cost me about $60 per oil change. And there was no typo, I run 9 quarts of oil at the oil change because this is the level I have found the V8 are delivered from the factory with. Have many 5.3l and 6.2l owners saw the same thing and are running 9 quarts without a single problem. 80% of my driving is highway and I have no negatives with 9 quarts, maybe 1/8" above the top of the has marks on the dipstick and again this is where I found the oil level when the vehicle was delivered to me.

 

[NELLY1947]

@NELLY1947,

You mentioned you are in Canada. While I assume the Summer weather is warmer, I bet the Winter is rather cold.

Not sure your driving habits, but in 40F ambient outside temps it takes about 25 minutes of driving to get the oil up to temperature to even start to cook some of the fuel out of the oil. I try to only use by truck when I plan on driving at least 30+ minutes. Additionally I have a Range DFM and ASS disabler on my truck. Often my typical driving habit is if I start the vehicle it will run for 1 to 6 hours at a time.

Before you deal with dealer on fuel contamination in the oil, check the air filter, think about your typical driving habits also understand if you are just now changing oil that was in the vehicle from last Winter you could have had fuel contamination from the colder weather.

Also DO NOT start the engine an allow it to warm up, it takes almost 2X longer for the oil to warm up at idle than with driving. I know in the Winter it is nice to Remote Start the truck and get in warm seats and a warm cabin, but this KILLS the engine oil with fuel, DO NOT DO IT.

The oil has been changed 5 times in 12000 miles with the last one also i never use thd stop light cut off. the truck is garaged all year round and it heated in the winter. also always drive ir for a minimum of 30 minutes when we start it. I know it's strange.

 

[JGinLA]

Our 2022 Premier was built without auto stop/start, thank goodness. Recently had the recall done. Just completed round trip from Lower Alabama to Upper West Virginia and back, less than 2000 miles if we stayed on the interstate. Went sightseeing in Shenendoah National Park, terrible MPG. Coming home on interstate, MPG was good and seemed to improve with each tankful if that means anything.

 

[jfoj]

I can say "terrible MPG" should not be from a different oil viscosity.

Not sure if GM ECM's are set up like some of the European DME's, but it almost sounds like either the dealer somehow cleared Adaptations and/or the ECM needs to relearn behaviors.

Did the performance feel different at the beginning of the trip and did performance change during the trip?

But also realize you were going from Lower Alabama where I have to assume it is relatively flat to areas all along the Appalachian mountain range. I know VA and West VA pretty well. Maybe you were just suffering from enjoying the 6.2l too much. You would surprised what even a slight grade will do to your MPG and the engine load when you are driving a 6k lb brick!

 

[RET423]

You could put 90 weight gear oil in the engine & you wouldn't feel the difference in performance

 

[Boston]

I have 84,000 on my 2022 Tahoe High Country and have NEVER used anything but 87 octane regular. I also have recorded 24.2 mpg while driving to Tampa (150 miles) with cruise set at 72 mph. That’s using regular fuel as well. While city stop and go during the slow season, I average 14.5 mpg and I baby my ride!

…87 octane with what engine? The 6.2 minimum requirement is 91 octane