Just finished two jobs with different hydraulic fluid brands

Had a call for a noisy pump on a 10 year old Dover unit. First, I used the generic bulk fluid the building manager had on hand. The noise dropped a little but came back in 3 days. Then I swapped it out for the specific AW 32 grade from the OEM supplier. The difference was night and day. The pump ran quiet and smooth right away. It's been two weeks now with no issues. Is it always worth pushing for the exact spec fluid, or do you guys find some generics are okay?

3 comments

3 Comments

blake7922mo ago

Yeah, that's the thing with generic fluids. They might meet the basic weight grade, but the additive package is totally different. The OEM's AW 32 has specific anti-wear and anti-foam agents that the cheap bulk stuff just skimps on. Your pump was basically telling you it was starving.

the_drew2mo ago

Ever think the cheap stuff was close enough? Hearing that pump whine changed my mind fast.

sagecooper2mo ago

Honestly, sometimes the generic fluid is fine and you're just paying for the brand name. That pump noise could have been from old fluid breaking down, not the new brand itself. You might have gotten the same result if you just flushed the cheap stuff twice.