Descrizione
On a D8R the implement pump does the work the operator feels: blade lift, tilt and ripper. Cat’s own parts literature files 9T-8346 as PUMP GP-PISTON (IMPLEMENT) and notes the slipper construction on the same page, which settles both the circuit and the type in one entry.
Applicability
CAT D8N track-type tractors and power-shift variants from prefix 5TJ 00001, and D8R from 7XM 00001, both powered by the Cat 3406. The D8R Series II literature covers AKA and BET groups on the 3406E. D8R II is listed in supplier data but is not individually booked against this number in the material we can check, so treat it as confirm by PIN.
One warning that applies to the current market: the modern Cat D8R is a completely different machine on a C15 ACERT. This pump does not fit it. If your fleet has both an older 3406 machine and a current-generation D8, the parts are not interchangeable and the model badge alone will not tell them apart.
Do not bundle the D8R pump with the D9R pump
104-1752 for the D9R and 9T-8346 for the D8N and D8R share a pump family and much of the same rotating group hardware, which is why aftermarket price lists print them side by side as though they were a set. They are two different pumps on two different tractors, with different control settings and different mounting groups. Our D9R page covers the other one. Order against the number on your own pump and the machine serial prefix, never against a supplier’s compatibility table.
Failure signs on a D-series dozer
- Blade lift slow and fading as the oil heats: pump wear. Test flow hot, not cold.
- Noise from the pump bay: cavitation from a restricted suction line or a tank filter that has not been changed.
- Ripper only weak: relief or control valve, not the pump.
- Oil at the shaft: check case drain back-pressure and the coupling, then the seal.
The comparison method is in our pump buyer’s and specification guide, e drive gear inspection covers what to look at on the input side before a new pump goes on.
Fitting and ordering
Match shaft spline, pilot, flange, port positions and the compensator setting against the removed pump. Prime the casing with clean oil before cranking. Change the return filter element and clear the suction strainer, targeting ISO 4406 18/16/13 for the piston components in the circuit. Keep the case drain unrestricted to tank. Prove blade and ripper speed against a hot machine and record the pressures.
Minimum order one piece. New aftermarket units carry a three to six month warranty as stated on your proforma invoice. Bench tested, photographed against your order before the wooden case closes, delivery 5 to 8 working days from payment subject to stock. The range sits under CAT hydraulic pump.
