What a difference - MMO + PCMO brand change

[CentAmDL650]

I am back with comments about my 01 Chevy Silverado 2500HD, 6.0L with 4 spd auto. It's about 5340 lb on the GM Pontiac factory's scales with (I was told at the dealer) 3 gallons of gas in it.

I've owned it since new, and after 2 short OCI's with VWB, then went to M1 10W30 thinking it would be the best for my application. Then later 5W30. Having a few jobs during that intervening time where I only went on trips 2 - 6 mile trips, and not seeing any or very little oil consumption, I seemed fine on the truck's recommended OCI + 1k, which turned out to be 4,800 to 5,200 + 1,000 = 5,800 - 6200 miles. Since the OM doesn't suggest syn, I thought I would be maintaining the motor in top shelf shape because I also used the stock AC filter.

Then sometime with around 45k miles I got an OCI that abruptly ended at about 5500 with the digital information center saying "Low Oil." It turned out to be 2 1/2 quarts low, some time in spring of '06. In one OCI my motor had gotten the oil consumption disease, and it looked like it was there to stay.

I've continued to run M1, and after adding a quart at 2k mi intervals I eventually got down to a quart every 1.2k - 1.4k, and changed oil right when the OLM recommended to. That was 2 1/2 years ago.

Then, so many on the PCMO board, made it sound like it would make more sense to use the one of the "High Mileage" versions of a major name brand to clean up the rings and reduce that consumption. Since then the mileage between adding a quart got up to 1800 miles. I was thinking there was some permanent wear in the cylinders or something. I seafoamed thru the PCV, then replaced the PCV, and even ran MMO in the gas, and got improved operating, especially at idle and significant throttle pull/ acceleration. I attribute it to the lubrication qualities in the pump and port FI system, maybe some intake valve cleaning. But I still didn't get the oil burn to a mileage I would have felt ok about, which I thought would have been over 2500 miles.

So 3 months ago, at 102,130 miles, when I was 1 quart down, I added a quart of MMO to the oil about 3500 miles into the OCI then ran for 830 miles with temps from 50's to 80's (F). I'm now 1800 miles into the next OCI also having switched to Motul 8100 5W30, and - I am shocked for almost 2 months into the OCI now, and am being convinced every day when I repeatedly pull the dipstick - the dipstick is now reading. . . less than 1/8 of a quart low!!! Never imagined that consumption could get this low. If it was a full 1/8th of a quart low that would translate to 1 quart every 14,400 miles!!!

Because I've made two changes in my oil regimen, there will be inevitably be those that cynically apply their scientific method and say my example proves nothing, or in reality, what they want it to prove.

Some will believe "snake oils" can't deliver as advertised.

Some will claim with certainty the using oil which is the "old school" or German definition of synthetic has no real benefit to your engine unless you're running tuned/ turbo/ high performance/ special fuels/ racing.

Some will sing the praises of Mobil 1, "full" synthetic with a group III comprised majority. How could there be anything wrong with "the" NASCAR synthetic you buy off the shelf?

Some will say the M1 HM oil was just waiting for its chance, and boom, after a 600 miles per quart improvement in round 15, and adding almost that many quarts between OCI's since starting the 4 OCI's on the HM diet, M1HM suddenly delivered the knockdown blow to my varnished rings, and bingo! Then like total opportunists, marginal and suspect products have stepped in to claim all the credit.

Some will demand an accounting of money spent through an oil change interval. In that time I would use 6 qts for the change and another 3 during the OCI. 9 quarts at $26 per 5 qt jug (incl sales tax) = $46.80 US. The Motul ran $50 / 5 liter jug (with shipping), and we all know 6 quarts = 5.68 liters + 0 quarts make up oil, which comes to $56.78 US, if I use the same OCI. I calculate would be breaking even on the oil expense if I could go to 6200 miles with no makeup oil, or about 1000 miles more than that with 1 quart of makeup oil.

Now I'll have to see if the Motul can hold up for the full OCI, go for and extended OCI, and hold up to a UOA. I'm sure a lot of credit goes to the MMO for dissolving the crud responsible for the blow-by and consumption, but I will entertain the inevitably harsh conclusions that must be drawn by the "anti-" critics.

 

[Stelth]

Thank you for a very interesting and informative post. I'll be interested to see if this (MMO and/or Motul) continues to work for you.

 

[silverrat]

Originally Posted By: CentAmDL650


Then sometime with around 45k miles I got an OCI that abruptly ended at about 5500 with the digital information center saying "Low Oil." It turned out to be 2 1/2 quarts low, some time in spring of '06. In one OCI my motor had gotten the oil consumption disease, and it looked like it was there to stay.


Did you not check your oil in the 5500 mile interval, since you were 2.5 quarts low all of a sudden?

 

[CentAmDL650]

No, then I was not in the habit of checking the oil level on the disptick except maybe when I added it in the change and right before I drained it when I changed. It had not used any significant amount up to that point, and my LT1 Z-28 (kept until it had 112,000 in '05) at the time also burned none. Both were bought new by me and fed a constant, steady diet of Mobil 1 - I think I had a very false sense of confidence to believe Mobil 1 was the last thing on either vehicle that would let me down.

 

[rockydee]

It looks like the mmo might have cleaned up sticking rings. That's been my experience fwiw. Look out though posting good results without proof [with any product] might get ya in some hot water.

 

[dave5358]

Originally Posted By: rockydee
It looks like the MMO might have cleaned up sticking rings. That's been my experience fwiw. Look out though posting good results without proof [with any product] might get ya in some hot water.

+1 on the sticking rings. This result should not be surprising to anyone familiar with MMO.

What kind of "proof" would you like him to post? No amount of proof will satisfy the anti-additive crowd, so let them just keep adding oil.

 

[4wheeldog]

I do not know if it was the MMO or the Motul, but something that starts with an "M" had the correct additives (Or solvents) to unstick your ring(s). I have had similar success by using Redline for an OCI, in a couple of vehicles that used oil. I went back to Mobil 1, after the Redline OCI, and consumption did not return.

(Mobil 1 was not in use when consumption started, but it didn't stop it either.)

Sometimes, a change in additive package can solve a specific problem.

 

[rockydee]

Originally Posted By: dave5358
Originally Posted By: rockydee
It looks like the MMO might have cleaned up sticking rings. That's been my experience fwiw. Look out though posting good results without proof [with any product] might get ya in some hot water.

+1 on the sticking rings. This result should not be surprising to anyone familiar with MMO.

What kind of "proof" would you like him to post? No amount of proof will satisfy the anti-additive crowd, so let them just keep adding oil.


lol You're right about not being surprised. Me I don't need proof, I already proved to myself, and that's all that matters to me.

 

[Mackelroy]

A good motor will run any oil without consumption. Back around 98 I bought a chevy 3/4ton, and the saleman told me they were loosening the top end for better fuel consumption.

I looked at him kinda crosseyed, but sure enough that truck would burn a 1/2 quart every 1500 miles. I burned chevy a new A$$ every survey I got. Your in that time frame. I don't know if GM still does this on its older design engines to improve fuel economy, I know my 2007 Colorado doesn't burn at all.

 

[chrisri]

You get what you pay for. In real word,in practice Motul has proved to be great choice.

 

[CentAmDL650]

I do have some suspicion of the motor because I've seen specs that say the pistons come with low tension rings. I thought low tension was to allow the engine to operate for long periods of time at high power levels with low risk of overheating, seizing, or excessive wear. For instance when pulling a large heavy trailer up a long, windy mountain pass at highway speeds+. The kind of operating parameters that send small and medium trucks to their graves, but something that's almost always responsible for at least some oil consumption.

Of course the low tension rings were just one piece to solving the high power output puzzle, as the LS series stopped trusting the earlier SB mains by going to the 6 bolt crossbolted design with deep skirts on the block, they added bigger oil and transmission coolers, higher flowing exhaust ports and short header-style manifolds, enormous 4" exhaust pipes throughout, and some form of steam ports in the pinched-in areas of the water passages in the heads. In fact I thought the HD trucks of that era were intended to be a halo model that would lure buyers into getting the much more mass-produced lower spec'ed 1/2 ton and less models.

Anyways, with an engine that I personally have known for so much oil consumption for the last 8 years, I am highly surprised it can nearly be stopped with a cleaner product and (maybe) a switch to another brand (which doesn't fit your theory that some engines turn into burners no matter what). Maybe low tension rings have a greater tendency to get stuck from varnishing and I just ought to run a cleaner in the oil every so many OCI's for preventative measures?