Caterpillar 590-9787 Hydraulic Oil Filter

The Hydraulic Number With No Size on the Box

Most aftermarket failures start with a supplier who publishes a number the original maker never published. 590-9787 is a case where the honest answer is thin: Cat gives the part name, the standard efficiency grade and a compatible list that spans about sixty machines, and nothing else we can check against a second source. That does not make the element hard to supply — it makes it hard to supply blind, which is the part buyers underestimate.

The reason a number like this sits on so many machines is that it is a common element in a shared hydraulic platform, not a machine-specific part. Wide coverage plus a name that reads like a generic category is how two different parts end up merged into one line on a purchase order: someone writes "hydraulic filter, 330 GC, quantity two", and the supplier picks whichever of 289-7789 and 590-9787 they stock.

How We Confirm It Without a Size

We ask for three things and nothing more: the outside diameter across the seal, the overall length over the end caps, and a photograph of the element next to a rule with the housing mouth behind it. From those, a match is either right or obviously wrong, and the second case is caught in Shanghai rather than at the customer's yard.

Where the machine is a 330 GC or 336 GC and the customer has both hydraulic elements to change, the order usually covers 289-7789 as well, because the two numbers sit in different housings on the same machine. If you have never had the two side by side, the eight-number kit guide sets out which of the two Cat names belongs to which published size, and where Cat publishes nothing at all.

Ordering It With the Rest of the C7.1 Set

Cat's page for this number lists 523-4987, 322-3155, 509-5694 and 500-0957 beside it, plus 580-5439 as a second cab air filter — the same group a service counter builds for these machines. Add the engine air pair 496-9845 with 496-9846 and you have the full C7.1 service set; the filters catalogue lists what we hold in stock for the 30 tonne class.

FAQ

Q: Which machines take the Cat 590-9787 hydraulic filter?
A: Cat's compatible list for 590-9787 runs from the 312 GX and 313 GC up through the 320, 320 GC, 323 GC, 326 GC, 330 GC, 336 GC, 345 GC, 349, 352, 355 and 395, and it also covers the 330 MHPU and 350 MHPU power units and the MH3040 to MH3260 material handlers. The 330 GC and 336 GC are both on it. A list that broad is a component-group list, so treat it as a starting point and confirm the housing.

Q: What are the dimensions of the 590-9787 filter?
A: Cat does not publish a measurement block for 590-9787 on its parts page, so we publish none either. Supplier listings that quote a size for it are giving their own bounding box, not a measurement of the element. Send the outside diameter, the overall length over the seal and a photograph of the element next to a rule, and the replacement is matched to those figures before dispatch.

Q: How is 590-9787 different from 289-7789?
A: They are separate Cat numbers with separate names: 289-7789 is the standard efficiency hydraulic and transmission filter, published as a cartridge 4.587 in (116.5 mm) across and 9.606 in (244.0 mm) long, while 590-9787 is a standard efficiency hydraulic oil filter with no published dimensions. 289-7789 covers roughly forty excavator models from the 320 to the 395, 590-9787 covers about sixty from the 312 GX. Both are listed for the 330 GC and 336 GC.

Q: What else is ordered with 590-9787 on a 330 GC service?
A: Cat's own page for 590-9787 lists 523-4987 fuel water separator, 322-3155 lube filter element, 509-5694 secondary fuel element, 500-0957 cab air filter and 580-5439 cab air filter alongside it, which matches the rest of the C7.1 service set. The engine air elements are 496-9845 and 496-9846, and the other hydraulic number is 289-7789.