Gasket makers

[Thunderbirds]

Hey all,

quick poll and looking for more insight into gasket maker material, and types. I am currently working on the geared hubs on the wheels. According to the TM, the gasket maker needed is an anaerobic (meaning it only cures in the absence of air), the differentials the TM called for RTV. Why the difference, both take Gear Oil? I used the black Permatex gasket maker especially made for Gear Oil on the differential covers. The red RTV that was used previously was "soaked" to describe it best, and it smeared when I rubbed my finger across it, that is why I looked up the Gear Oil gasket stuff.

Does anyone have a scientific reason for different gasket makers on the diff and geared hub? Could one use the black gasket maker instead of the anaerobic stuff?

Wanted to see what other have done, and the result.

Thanks!

 

[Mogman]

The anaerobic is normally used for machined surfaces and the RTV is for pressed (tin) surfaces

 

[juanprado]

For differentials and other applications with gear oil, Permatex makes a specific rtv, Others will work that are universal but worth getting this one. YMMV

Permatex® Gear Oil RTV Gasket Maker, 3 OZ - Permatex

www.permatex.com

 

[Thunderbirds]

For differentials and other applications with gear oil, Permatex makes a specific rtv, Others will work that are universal but worth getting this one. YMMV

Permatex® Gear Oil RTV Gasket Maker, 3 OZ - Permatex

www.permatex.com

Yea ,I saw that but this was more available and half the price....

Permatex® Ultra Black® RTV Silicone Gasket Maker, 3 OZ - Permatex

www.permatex.com

I hope the black RTV is as good as the green you pointed out.

The anaerobic is normally used for machined surfaces and the RTV is for pressed (tin) surfaces

That is awesome information... That makes sense 'Geared hub, vs differential'. Thanks!

 

[Guyfang]

I thought RTV Red was meant for high temp areas. Or someone can straighten me out?

 

[juanprado]

I thought RTV Red was meant for high temp areas. Or someone can straighten me out?

Yes, But many folks use it as a universal rtv. It seems it must be the to go to item for the military as my M923 & m998 only have red on anything that has been "serviced" . My 2 differentials were leaking on the m998 from the red rtv but to be honest it looked like it had been gooped on. Clean surfaces is key to any sealing rtv to work properly.

 

[Thunderbirds]

The anaerobic is normally used for machined surfaces and the RTV is for pressed (tin) surfaces

Can I use the normal gear oil silicone (black stuff) for the hubs? Thoughts?

 

[98G]

Can I use the normal gear oil silicone (black stuff) for the hubs? Thoughts?

I did in 2019. No issues since. I've put maybe 15k miles on it in a mixture of sustained interstate road trips and very tame off roading.

Yeah, I'm a sample size of one. Take that fwiw.

 

[Thunderbirds]

I did in 2019. No issues since. I've put maybe 15k miles on it in a mixture of sustained interstate road trips and very tame off roading.

Yeah, I'm a sample size of one. Take that fwiw.

Thanks for the heads up. I'll probably do the same, just because I did the diffs first and thought it would call for the same on the hubs, so I bought enough for all. And I don't understand the Anaerobic character need, maybe someone knows?


EDIT:

And there I go and find out:

This site https://www.metlok.in/blog/face-sealing-anaerobic-or-silicone-sealant/ says amongst other characteristics and is pretty interesting.


-Anaerobic Adhesives and sealant will offer 100% metal to metal contact and hence are the preferred Sealants of choice for machinery assembly.


– RTV Silicone Sealants may not offer 100% metal to metal contact as they are highly filled and very high viscosity materials.

 

[osteo16]

Hey all,

quick poll and looking for more insight into gasket maker material, and types. I am currently working on the geared hubs on the wheels. According to the TM, the gasket maker needed is an anaerobic (meaning it only cures in the absence of air), the differentials the TM called for RTV. Why the difference, both take Gear Oil? I used the black Permatex gasket maker especially made for Gear Oil on the differential covers. The red RTV that was used previously was "soaked" to describe it best, and it smeared when I rubbed my finger across it, that is why I looked up the Gear Oil gasket stuff.

Does anyone have a scientific reason for different gasket makers on the diff and geared hub? Could one use the black gasket maker instead of the anaerobic stuff?

Wanted to see what other have done, and the result.

Thanks!

Just from my thining, Anerobic may be used in stressed areas. Such as the stearing knuckle. No give between surfaces, where as a rubberized sealant would have movement. This is mearly my deduction, but sounds good.

 

[Dieselmeister]

Anerobics allow adjustment of the parts, until they are clamped together. Most Anerobics are very poor at filling any large gaps. They are for machined surfaces as someone previously stated. RTV's (Room Temperature Vulcanizing) sealers can fill gaps, but start to cure as soon as exposed to air. If you apply RTV, and take a long break before assembling the parts, you may have to scrape it all off, and start over. Cured anerobics can usually be removed with the correct solvent. Cured RTV's usually need to be removed mechanically. As always, all parts must be absolutely clean prior to applying either sealer, or they will leak!

 

[87cr250r]

Use anaerobics anywhere you can. Silicone is very permeable and can seep oil. Silicone glues the parts together which makes disassembly difficult. Silicone is more difficult to clean up. Silicone contaminates surfaces for painting. Silicone makes chunks that can clog things up.

Anaerobics are not typically effective on sheet metal because they are not flat enough to exclude oxygen and may not cure.

Anaerobics are not as heat tolerant as silicones.

 

[Mrgior31513]

Can I use the normal gear oil silicone (black stuff) for the hubs? Thoughts?

I prefer the black silicone in most uses that are general engine or gear oil applications and not high heat. I've done mostly civilian mechanic work, but I have not had a problem with diffs and general engine use when using black. I picked up that habit from mechanics that have been doing it longer than I have, years ago. On my 6BT engine build I bought a full tube of the black stuff to use, and I'm following an engine builder that is far more savvy that myself for my first diesel engine.
Don't really have any experience with anaerobics, so I'm not what you could call an expert in the realm of sealants in greater detail.

 

[Mogman]

Can I use the normal gear oil silicone (black stuff) for the hubs? Thoughts?

You can probably get away with it, but you must think your labor has no value if you are willing to do the job twice.
As stated above surface prep is key to any sealing job

 

[Thunderbirds]

...but you must think your labor has no value if you are willing to do the job twice...

And that is the main reason I started the topic, I agree 100%. Sort of a constant battle in my head when one side wants me to get the job done, the other screams just what you said.

I finished the two front hubs with the black gear oil resistant yesterday morning because that is what I had in the house, but am I fully content wit that decision? 'can't really say that I am. I hope it will work out, but if I have the slightest leak over the next few years, I'll re-do both with the anaerobic. That stuff is just not that readily available.

Almost staying on topic, both drain plugs were all chewed up, so found these in FleaBay

(Bad input, do not order)

I offered a lower amount and got them for $3 a piece including shipping. Now, since I am done with both diffs and couldn't even budge the drain plugs, I plan on replacing them next time so I don't have to go through the cover removal/maintenance labor again. The service intervals in the TM calls for semiannually or 3,000 miles for the M1123 and M998A2. I don't want to stray from that too far. Transmission and transfer case plugs were good. I guess I just had one shady Marine mechanic service the diffs and hubs and stripped the 6 plugs.

Thanks all for your input. A lot of great expert knowledge on RTVs and Sillicones. Hope this helps someone else besides me.

 

[gringeltaube]

.......... I hope it will work out, but if I have the slightest leak over the next few years, I'll re-do both with the anaerobic. That stuff is just not that readily available.

Not?? Do a search for Henkel's "Loctite 518". There are at least three different sizes to choose from: 6ml and 50ml tubes and also a 300ml cartridge. Available everywhere; Napa, eBay, Amazon, they all carry them.

Not the cheapest gasket maker ever, but unlike silicone and PU sealants, this stuff does not expire and cure inside the tube.
I still have some left in a 300ml cartridge that is over 10 years old; it still works like the first day!

 

[Thunderbirds]

Not?? Do a search for Henkel's "Loctite 518". There are at least three different sizes to choose from: 6ml and 50ml tubes and also a 300ml cartridge. Available everywhere; Napa, eBay, Amazon, they all carry them.

Not the cheapest gasket maker ever, but unlike silicone and PU sealants, this stuff does not expire and cure inside the tube.
I still have some left in a 300ml cartridge that is over 10 years old; it still works like the first day!

You're right, they are all available online, even free shipping to the house, but here in these neck of the woods, I couldn't find ANY anaerobic readily available in store.

The not curing inside the tube is definitely a positive aspect!

 

[Mogman]

And that is the main reason I started the topic, I agree 100%. Sort of a constant battle in my head when one side wants me to get the job done, the other screams just what you said.

I finished the two front hubs with the black gear oil resistant yesterday morning because that is what I had in the house, but am I fully content wit that decision? 'can't really say that I am. I hope it will work out, but if I have the slightest leak over the next few years, I'll re-do both with the anaerobic. That stuff is just not that readily available.

Almost staying on topic, both drain plugs were all chewed up, so found these in FleaBay

5pcs AA59432-12 Magnetic Pipe Plug | eBay

This item is to be installed and maintained by qualified individuals. We claim no expertise in the use of this item. We accept no responsibility on the correct/incorrect application or installation of this item.

www.ebay.com

I offered a lower amount and got them for $3 a piece including shipping. Now, since I am done with both diffs and couldn't even budge the drain plugs, I plan on replacing them next time so I don't have to go through the cover removal/maintenance labor again. The service intervals in the TM calls for semiannually or 3,000 miles for the M1123 and M998A2. I don't want to stray from that too far. Transmission and transfer case plugs were good. I guess I just had one shady Marine mechanic service the diffs and hubs and stripped the 6 plugs.

Thanks all for your input. A lot of great expert knowledge on RTVs and Sillicones. Hope this helps someone else besides me.

View attachment 925414

Where did you get the numbers for these magnetic plugs?
(DO NOT ORDER THESE!!)
These are 3/4 NPT you are going to have one hell of a time trying to thread these into ether the drain or fill plug holes on those diffs.
Oh well I guess I have them just in case I ever actually need them, of course I should have researched them myself, another lesson learned...
BTW the correct plugs would be a -8 not a -12

 

[Thunderbirds]

Where did you get the numbers for these magnetic plugs?
These are 1" NPT you are going to have one hell of a time trying to thread these into ether the drain or fill plug holes on those diffs.
Oh well I guess I have them just in case I ever actually need them, of course I should have researched them myself, another lesson learned...
BTW the correct plugs would be a -8 not a -12

Simple actually, if you put them in the wash and then into the dryer on high temperature for about 45 minutes, the shrink ratio is exactly 49.74%, (the rest is negligible you may have to fill the rest in with RTV).





Just kidding, aaaagggghhhhh!!!!!!! I did an Ebay search and the stupid site must have given me the "similar Items" and I did not catch that! Dangit.... I was so excited to have found them.

Did you buy them after I posted, or did you catch that in time, couldn't tell from your post? I am sorry if you went on my recommendation and ended up with a $15 paperweight. I'll have to offer them up on Ebay or Craigslist with a few dollars loss.

You are correct on the -12 vs -8 part number. That is how I ended up in this mess. My plugs haven't arrived yet so I was spared of my shame for a day or so, until you lit me up.

Seriously, if you bought them on my recommendation, I apologize. Could you as a Moderator possibly delete the link so others aren't fooled by my idiocy?

 

[Mrgior31513]

Seriously, if you bought them on my recommendation, I apologize. Could you as a Moderator possibly delete the link so others aren't fooled by my idiocy?

Can you edit the post to remove the link?