PPNZQAUT windscreen washer reservoir for Peterbilt 1989–2007 — replacement tank with pre-installed pump & cap, heavy-duty fit

The PPNZQAUT 603-5404 is a heavy-duty replacement windshield washer reservoir assembly—complete with pump and cap—designed to restore washer function on compatible Peterbilt trucks.

If your Peterbilt’s washer system no longer holds fluid, sprays poorly, or has a cracked tank, this aftermarket replacement restores the reservoir, pump, and cap in one unit. Built to match the fit and connection points of the original equipment, it replaces part numbers 603-5404, 6035404, and R86-6001 to get your washer system back in working order without sourcing multiple components separately.

How will this reservoir fit my specific Peterbilt model?

This PPNZQAUT reservoir is manufactured to match the fit and mounting points of specified Peterbilt models so it installs in place of the original tank. Fitment covers select years and models—always verify year, make, and model before purchase to ensure compatibility.

• Compatible with 1989–2007 Peterbilt 357
• Compatible with 1989–1999 Peterbilt 375
• Compatible with 1989–2007 Peterbilt 377 and 379
• Replaces OEM part numbers 603-5404, 6035404, R86-6001

What components come with this replacement assembly?

The unit ships as a ready-to-install assembly including the molded reservoir, an electric washer pump, and a matching cap. That reduces the need to buy separate pump modules or gaskets and helps simplify the repair process.

• Pre-installed washer pump for immediate operation
• Matching threaded cap for a secure seal
• Molded tank body shaped to original mounting locations
• Electrical connector and hose attachment points aligned to OEM layout

How durable and reliable is this aftermarket replacement?

PPNZQAUT designs this reservoir from durable materials intended for heavy-duty truck environments. While it is an aftermarket (non-genuine) part, it’s manufactured and tested for fit and performance on the listed Peterbilt applications to ensure long-term service under normal use.

• Rigid molded construction resists cracking and warping
• Corrosion-resistant pump and fittings for extended life
• Tested for correct fit and sealed connections
• Designed to withstand standard road vibration and temperature ranges

How difficult is installation and what should I prepare?

Installation requires removing surrounding components and unfastening the old reservoir’s mounts, hoses, and wiring; the new unit installs in reverse order. If you’re comfortable working with basic truck electrical and fluid lines, you can perform the swap, but professional installation is recommended if you lack tools or experience.

• Recommended tools: basic hand tools, pliers, and possibly a small jack or lift
• Drain fluid and disconnect electrical connector before removal
• Inspect hoses and nozzles—replace if brittle or clogged
• Test pump and spray pattern after installation to confirm operation

Who is this replacement assembly for? This PPNZQAUT 603-5404 reservoir assembly is intended for fleet owners, owner-operators, and mechanics servicing older Peterbilt trucks (1989–2007 models listed) who need a one-piece, ready-to-install washer tank with pump and cap. It’s a practical, cost-effective alternative to sourcing separate parts or locating scarce OEM components—ideal when the original reservoir is cracked, leaking, or the pump has failed and you want a durable aftermarket solution that restores washer functionality quickly.