Deere 550A and 550B: blade fit and hydraulic test conditions

The 550B pump test pressure is not the dozer relief setting

Deere's dated 550B service guide measures implement-pump flow at a specified engine speed and test pressure. Its dozer relief setting appears separately. Treating the test pressure as the relief adjustment would confuse two different specifications.

The guide also separates large and small implement pumps, with different acceptance figures for new and used pumps. A flow result therefore needs the pump arrangement and test conditions alongside it. The transmission pump has its own flow and pressure checks; an implement-pump result does not establish transmission condition.

Refill quantity depends on the attachment installation. The hydraulic reservoir, complete blade system, individual final drive and steering-clutch housing are separate entries. Engine-oil capacity changes at an engine serial break.

Match those boundaries before ordering fluid. These 550B service figures do not establish identical settings for a 550A.

Identify the blade assembly before ordering its cutting edge

ESCO's blade catalogue groups the 550A and 550B with several blade assemblies, rather than giving each tractor badge one universal cutting edge. Its chart distinguishes a centre section from the end pieces and lists their hole patterns separately. An advertised edge “for a 550” therefore needs more identification.

For example, the catalogue's 7711/6410 group uses an 81.88-inch centre with nine holes. Its 6400/6405 group lists a much shorter centre with seven holes. Those are different bolt-on pieces even though the table includes the same tractor family.

The end pieces appear as separate quantities, with their own dimensions and fasteners.

Before requesting a quotation, record the blade identification, existing part number, centre length, hole count and bolt spacing. Include photographs showing both ends and the centre joint. Ask the supplier to match the complete row, including thickness and bolt specification.

ESCO is the replacement-edge manufacturer here; this catalogue is evidence for its listed products, not proof that a particular used tractor still carries its original blade.