Best penetrating lubricant

[JHZR2]

On my 2008 ML320, the driver side door hinge is getting a bit noisy.

An eBay screen grab shows what the hinges look like. Somehow the door check and hinge is all built inside.

I’ve tried superlube without any success. These hinges have no access for grease, no grease point like the older MB hinges, etc.

So I think I need to have something that penetrates much more. Not sure if that means first dousing and flushing with acetone, WD-40, etc.

Acetone/ATF seems maybe like a good option, other than do I really want acetone sitting on a painted part?

I know @Trav spoke highly of Gibbs penetrating and lubricant.

I don’t know if I only want a penetrant to start, then a lube to wick in, or what.

Thoughts??

 

[wings&wheels]

I'm partial to Cyclo and Kroil penetrants and I would consider Wurth HHS-K/HHS + (or whatever the current name is) after you free and clean the parts. HHS applies as a thin penetrating liquid that sets up to a sticky, stringy grease. Good stuff for this and similar applications.

 

[Trav]

I would be tempted to see if it were possible to install a flush zerk similar to the ones used on old models. Something like this?

https://zerksplus.com/1-8-27-npt-flush-straight-slotted-grease-zerk-nipple-fitting-2-pcs/

 

[Ausfahrt]

As you mentioned, ATF and acetone mixed 50/50 works as good as anything you can buy. If you get it freed up I would follow with fluid film.

 

[FowVay]

My absolute favorite penetrating oil is Schaeffer's Penetro 90. I love it because it weeps into tight cracks and it contains a zinc element that also lubricats once it has penetrated the surfaces. It will leave a white residue on plastics if you don't clean it up.

 

[dippschtick]

Silikroil
Kroil w/silicone

 

[4WD]

Wait for Toyota to mainstream 0W-2 and you’d have PO @ $5/quart

 

[NOTEVIL81]

Kroil and little heat

 

[shortyb]

What about traditional white lithium grease? I have CRC brand and it seems to migrate pretty well. Lubricates for a long time and stays put. Another idea is to use a motorcycle chain wax. Starts very fluid and then penetrant flashes off and leaves a waxy lubricant behind. I use it on wheel bearings of lawn mowers with great success. Still have 2 cans of the Schaeffers Penetro 90 that @FowVay mentioned. Its a bit thin for lube but penetrants very well.

 

[demarpaint]

Another vote for Gibbs oil.

 

[SC Maintenance]

The problem with most penetrating oils is there not actually a lubricant.

The key to sneaking around seals is a lubricant with very low surface tension. In the industrial world we use low surface tension fluids for lots of things, and our problem is keeping it out of places it shouldn't be, not getting it in. The getting in part is known as "creep". Based on this if I were in your boat I would try something silicon based first. Low viscosity silicon has very low surface tension.

I have actually found the liquid silicon designed for treadmill belts works really good on lots of stuff.

 

[JHZR2]

The problem with most penetrating oils is there not actually a lubricant.

The key to sneaking around seals is a lubricant with very low surface tension. In the industrial world we use low surface tension fluids for lots of things, and our problem is keeping it out of places it shouldn't be, not getting it in. The getting in part is known as "creep". Based on this if I were in your boat I would try something silicon based first. Low viscosity silicon has very low surface tension.

I have actually found the liquid silicon designed for treadmill belts works really good on lots of stuff.

That’s my concern. That’s why I’m thinking a multi-step may be needed.

The big issue is weeping into fine cracks and getting where it needs to go. Thus the penetrating capability is important all the same.

Another vote for Gibbs oil.

I did order some. It says lubricant…

What about traditional white lithium grease? I have CRC brand and it seems to migrate pretty well. Lubricates for a long time and stays put. Another idea is to use a motorcycle chain wax. Starts very fluid and then penetrant flashes off and leaves a waxy lubricant behind. I use it on wheel bearings of lawn mowers with great success. Still have 2 cans of the Schaeffers Penetro 90 that @FowVay mentioned. Its a bit thin for lube but penetrants very well.

If superlube didn’t make it in, no way spray grease will.

As you mentioned, ATF and acetone mixed 50/50 works as good as anything you can buy. If you get it freed up I would follow with fluid film.

Ditto for fluid film. Dubious it would work in. Acetone should creep though. While it’s ruining my paint…

My absolute favorite penetrating oil is Schaeffer's Penetro 90. I love it because it weeps into tight cracks and it contains a zinc element that also lubricats once it has penetrated the surfaces. It will leave a white residue on plastics if you don't clean it up.

I do have some of that someplace!!

 

[Danno]

My vote is for Krown rust prevention spray or similar.
Tends to stick to parts, penetrate and creep.
I use Krown on my garage door torsion springs and sleeve hinges.

 

[facility1]

Schaeffer's Pentro 90 would be a good choice or Tri-flow (black can) works quite well found at many hardware stores.

 

[Pablo]

Are you sure it’s just a lubrication issue?

 

[50yr Street Mech]

Hands down. KROIL with a tad of the " blue wrench". Never failed me yet. It's flammable, so be careful around painted surfaces. I use it mostly on " Rust Belt" suspension parts.,,,and the occasional steel wheel stuck to the hub.

 

[RaymondP]

3 in 1