Colloidal moly buildup in pan

[SnowDrifter]

Been using a mos2 additive regularly for the last 40k miles on account of some better UOAs and, well, I'm the guy that splits hairs like that.

Dropped my pan down to do some maintenance and I found this rather thick sludgy stuff at the bottom of the pan. Not a lot, maybe a couple teaspoons worth in total. But it's there, hiding in the corners at the bottom. Did some inspecting on it since my engine has an exceedingly good service history and igbdfwiswe has no sludge or anything beyond a light varnisn, and found it to resemble the Mos2 additive I've been using. The stuff looked and felt like a thin grease.

I've not experienced any clogged filters or other concerns, and based on the amount, I think most of it stayed in suspension. But a little bit from each OCI seems to have settled out in the pan and formed a layer of gunk that just wouldn't agitate and suspend even after a 5 hour road trip.

If I was thinking ahead I would have taken come pictures. That bit only occurred to me after the fact.


Not going to name brands here as its really not my goal. Consider this more of a PSA, where something that might be good in the short term, or even mid term, isn't great long term. I reckon if I would have continued use to 150k miles or so I might run into issues with plugging the pickup screen.

Edit: I should add this vehicle isn't driven daily. It's used 1 to 3 times a week

 

[JC1]

Thanks for letting us know.

I'm guessing you cleaned it up and put it all back together? Are you going to continue to use mos2?

 

[Mainia]

I have been told by and oil engineer and seen on some pumps that I used that product on at work....it takes out seals way earlier then if did not use it. I stopped and so did the pump seal leaks.

 

[demarpaint]

Trav had the same issue and posted pictures of the inside of the pan from a vehicle he used MoS2 in. As a result many members stopped using it. It appears to fall out of suspension in vehicles that aren't driven everyday. Your findings back it up, only you use your vehicle a lot more often than Trav drove his. I'd be willing to bet even daily drivers will have some fallout with the product if they use it long enough, as in several years.

 

[Shannow]

Yep, Trav brought it to the board, and I think JHZR2 did some numerical analysis to prove that it could and would happen.

Pretty hard to get enough "swirl" in localised deposits to get them picked back up....look at the fine sand that gets accumulated in the places that fine sand accumulated.

 

[SnowDrifter]

Originally Posted by JC1
Thanks for letting us know.

I'm guessing you cleaned it up and put it all back together? Are you going to continue to use mos2?

Yeah she's all buttoned up. Just letting the Rtv dry overnight

I don't plan on using it any more. There's a risk/reward thats just not there for me at current. Engines are long lived if well maintained. That lifespan shortens drastically if an oil passage gets plugged.

Originally Posted by Mainia
I have been told by and oil engineer and seen on some pumps that I used that product on at work....it takes out seals way earlier then if did not use it. I stopped and so did the pump seal leaks.


Seriously? It wears out seals faster?

Well. Looks like I'm changing my power steering fluid too. I tossed a splash in there to try and quiet a noisy pump. The punp isn't a big deal but the hydroboost setup is a right pain in the [censored] to service. Don't want to do that any sooner than I possibly need to

 

[Virtus_Probi]

Does this still happen with the oil soluble MoDTC/MoDTP/etc additives?
I thought I read here that they end up breaking down to MoS2 at the high temp/pressure interfaces and don't know if it's possible that they stay in that state long enough to precipitate out.

I used to add small amounts of LM MoS2 to my oil and dropped that after Trav's post...maybe people who still want to add moly could find an oil soluble additive?

 

[CT8]

Do we know the deposits were actually MoS2? and how do we know if the filter was actually clogged or not? I am not a fan of aftermarket adds. I have never seen a benefit though some mechanic in a jug can camouflage some problems.

 

[PimTac]

With the modern oils as good as they are plus all the intricacies of modern engines, I would hesitate to use any kind of additive. This would be even more so in a vehicle that is not driven all the time.

 

[Revving2Redline]

Originally Posted by SnowDrifter
Been using a mos2 additive regularly for the last 40k miles on account of some better UOAs and, well, I'm the guy that splits hairs like that.

Dropped my pan down to do some maintenance and I found this rather thick sludgy stuff at the bottom of the pan. Not a lot, maybe a couple teaspoons worth in total. But it's there, hiding in the corners at the bottom. Did some inspecting on it since my engine has an exceedingly good service history and igbdfwiswe has no sludge or anything beyond a light varnisn, and found it to resemble the Mos2 additive I've been using. The stuff looked and felt like a thin grease.

I've not experienced any clogged filters or other concerns, and based on the amount, I think most of it stayed in suspension. But a little bit from each OCI seems to have settled out in the pan and formed a layer of gunk that just wouldn't agitate and suspend even after a 5 hour road trip.

If I was thinking ahead I would have taken come pictures. That bit only occurred to me after the fact.


Not going to name brands here as its really not my goal. Consider this more of a PSA, where something that might be good in the short term, or even mid term, isn't great long term. I reckon if I would have continued use to 150k miles or so I might run into issues with plugging the pickup screen.

Edit: I should add this vehicle isn't driven daily. It's used 1 to 3 times a week


If you are looking for moly try the Lubegard Biotech or replace a qt for a qt of redline oil to boost molybdenum ppm.I quit using mos2 after going to Archoil and Redline. I did however use the Gumout Multitune in the fuel and crankcase 50 miles prior to help remove the old black tar.

 

[Whipcitywrencher]

Originally Posted by SnowDrifter
Been using a mos2 additive regularly for the last 40k miles

I've not experienced any clogged filters or other concerns, and based on the amount, I think most of it stayed in suspension. But a little bit from each OCI seems to have settled out in the pan and formed a layer of gunk that just wouldn't agitate and suspend even after a 5 hour road trip.

Edit: I should add this vehicle isn't driven daily. It's used 1 to 3 times a week


Thanks for posting your findings.

 

[SnowDrifter]

Originally Posted by CT8
Do we know the deposits were actually MoS2? and how do we know if the filter was actually clogged or not? I am not a fan of aftermarket adds. I have never seen a benefit though some mechanic in a jug can camouflage some problems.

If you're asking if I sent a sample off to a lab for chemical analasys, the answer is no. Process of elimination. The engine has no mechanical issues, no sludge or other concerns internally, and sees regular oil changes with a well known brand. I'm sure I could scrape some off my oil drain and mail it to you if you're interested. It's still sitting there from when I scrubbed it out. I just don't care enough to pay for lab tests on some junk at the bottom of the pan particularly when the product use and result aligns with other members findings here.

Cutting a filter open is a thing. A visual inspection will tell if it's clogged or not.

Nothing was camouflaged. There are no issues with my engine. It was indented as a life extending measure

 

[panthermike]

Thanks for sharing, I use to occasionally use the product but due to findings like yours, i have stopped. I now only use Lubegard Biotech since they utilize soluble moly