Mobil SHC-32

Joined
Aug 30, 2004
Messages
31,975
Location
CA

My new Snap-On cordless ratchet specs this grease. You are supposed to lube it "daily" under heavy use.

Questions:
1) This grease is NLGI 1.5; most "chassis greases" are NLGI 2. Is this a significant difference in viscosity? This Mobil product appears to be difficult to obtain....and expensive.
2) Are compatibility issues a true concern for petroleum based greases, or is it an urban myth? Is it necessary to "flush out" the old grease with new if you are switching to a different type/brand?
 
E6558516-505F-4A91-A75A-63029D9BB613.png

I use this for my air and electric tools that have grease fittings it works well for me even in the high speed die grinders I have. As you can see it’s the Mobil SHC-32 speced for it just under a snap on label.

You do have to buy the mini grease gun for it though, the part number is under the features section. One tube lasts a long time.
 
Last edited:
I’ll chime in when I can gather my thoughts. Had a death in the family so my mind just isn’t all there. And I don’t want to say something half cocked.

Sorry.
 
The NLGI grade refers to consistency (hardness) and not viscosity. The test method is ASTM D217. The measurement is “depth of penetration of a standard brass cone into the worked grease”. The unit of measure is decimillimeter or dmm.

An NLGI 2 has a worked penetration of 265-295 dmm. An NLGI 1 has a worked penetration of 310-340 dmm. A 1.5, which is not a real NLGI grade, should have a worked penetration of 296-309 dmm. However, it may be widened to something like 290-315 dmm.

The “32” refers to base oil viscosity which is an ISO 32 PAO.

The grease’s thickener is clay. Clay greases are notoriously incompatible with metallic soap-based grease such as lithium, lithium complex, aluminum complex.

If the ratchet is lubricated with this grease and you want to change, I suggest that you clean the bearing completely and relubricate. If you can’t clean the bearing, I would purge with the preferred grease and then relubricate frequently until you are confident that the clay grease is removed. You can always just use the recommended grease.
 
The NLGI grade refers to consistency (hardness) and not viscosity. The test method is ASTM D217. The measurement is “depth of penetration of a standard brass cone into the worked grease”. The unit of measure is decimillimeter or dmm.

An NLGI 2 has a worked penetration of 265-295 dmm. An NLGI 1 has a worked penetration of 310-340 dmm. A 1.5, which is not a real NLGI grade, should have a worked penetration of 296-309 dmm. However, it may be widened to something like 290-315 dmm.

The “32” refers to base oil viscosity which is an ISO 32 PAO.

The grease’s thickener is clay. Clay greases are notoriously incompatible with metallic soap-based grease such as lithium, lithium complex, aluminum complex.

If the ratchet is lubricated with this grease and you want to change, I suggest that you clean the bearing completely and relubricate. If you can’t clean the bearing, I would purge with the preferred grease and then relubricate frequently until you are confident that the clay grease is removed. You can always just use the recommended grease.

This is 100% the correct answer.

And thank you to everyone who sent me DM’s. It’s been a rough few days. Meant to reply earlier today but went to the office for the first time and had to play catch up.

RDMgr knows his stuff. Listen to him.
 
Back
Top