Compatibility

Base stocks are the key element. If they are both PAO you shouldnt have a problem. PAO and PAG bases stocks are not compatable.

For what application?

This is for Gearbox and hydraulic lubrication.

Since the laboratory result is showing OK, Do trial first on the non-critical equipment.
if OK for 3 months, go ahead.

usually incompatible oil, will resulting on foam problem, or aglomeration of additive which resulting high oil filter DP for forced lubrication system

Was the laboratory did the test of foam characteristic also (ASTM D 892)?

Dear Amit, Please explain relation of mixing of PAO with energy saving? I did not get your point......

Dear Nurudin, lab test report neither show any foaming nor separation.

Lubtech,

how big the lube oil tank capacity?
did you mixed it already?

quote:

Need guidance on compatibility of two different PAO based gear oils (different make) with same ISO VG number. Can they mix?

As lab test report does not show any reaction or deterioration of physical properties.

Hi Lubtech,
I'm 99% sure it will be fine but as you already have the lab report go and compare the two additive packages in the spectrographic analysis results on the two gear lubricants and if there is a major difference, most likely not, check with the supplier of the replacement lubricant that it will be OK,
Regards
Rob S

quote:

Originally posted by lubtech:
Dear All,

Need guidance on compatibility of two different PAO based gear oils (different make) with same ISO VG number. Can they mix?

As lab test report does not show any reaction or deterioration of physical properties.

Hi lubetech,

There is an ASTM method for the evaluation of compatibility - ASTM D 7155 (established in Nov 2006).
If you are going to test compatibility of any 2 oils, I'd suggest YOU send samples to a lab for testing rather than the new oil supplier (interest-bound party). I’m saying this because the method is quite subjective and its results (actually done by visual observation) could be easily misread and misinterpreted, which could potentially be harmful to the end-user (you). I have seen it done that way.
If you decide to do it, request only Tear 1 part of the test because it is quite informative and much cheaper than the whole test (Tier 1 + Tier 2). If you have a chance, get a hold of the method and read it and you will know what I am talking about. Feel free to contact me if you need more info about it.

As a side note, base oils of all PAO blended oils are fully compatible. The possible problem with incompatibility starts with mixing different additives in them that may not be fully compatible.

Good luck