GMAX II 5900 HD Lo-Boy is the workhorse of gas-powered airless sprayers: a 3300 psi, 1.6 gpm rig that atomizes everything from block-fillers to high-solids elastomerics—yet rolls under a truck topper thanks to its low-profile frame. When that kind of output is your profit engine, down-time is simply not an option. SprayersAndParts.com stocks every OEM seal, rod, and sensor you need.

Six Reasons Pros Demand Genuine 5900 HD Components

Chromex™ Endurance Pump. Hardened stainless rod and Vortex MaxLife™ swirl ports last 2× longer than chrome-plated aftermarket rods.
Exact-fit machining. Seats and balls are ground to ±0.001 in, preserving the sprayer’s 3300 psi ceiling even on 150 ft hose runs.
Warranty intact. Only genuine parts keep your pump, clutch, and Honda® engine under Graco’s 12-month coverage.
BlueLink™ compatibility. Serialized boards sync run-hours, pressure logs, and rebuild history for data-driven maintenance scheduling.
Higher resale value. Fleet surveys show OEM-serviced GMAX rigs fetch up to 17 % more at auction.
Sustainability. 90 % of our cartons are curbside-recyclable, and every lithium pack ships in IATA sleeves.

Core Performance Specs at a Glance

Max working pressure — 3300 psi / 228 bar
Max flow rate — 1.6 gpm / 6.0 L min-¹
Max tip size (single gun) — 0.043 in; two guns — 0.056 in
Engine — 160 cc Honda GX OHV with Oil Alert®; 118 dB Lwa
Hose capacity — 150 ft / 46 m BlueMax II anti-static line
Recommended production — 100–200 gal week-¹ for 3-man crews

Cross-Platform Compatibility: Stretch Your Parts Budget

GMAX II 7900 HD & TexSpray 7900—share clutch, pressure control board, and RAC X guards; stocking graco 7900 parts covers both rigs.
Ultra Max II 595 & 495 PC Pro—identical pump packings and suction tube O-rings; one kit services electric and gas fleets.
Magnum X5 / LTS 15—gun needles and 515 LP tips cross-fit; our Graco X5 and LTS 15 Diagram and Parts List maps shared components.
Handheld sprayers (Ultra Cordless, TC Pro, TrueCoat 360)—use the same RAC X LP tip sizes, so your field kit supports both graco handheld sprayers and the 5900.

Top-Moving Replacement Categories

Pump lowers & clutch kits. Swap a worn lower in under three minutes using ProConnect™ studs.
RAC X spray tip guards. HandTite™ design eliminates build-up and finger burns at 3300 psi .
Graco suction tube assemblies. Stainless 8-mesh strainer plus Viton® seals resist hot solvents.
BlueMax II hose packs. Anti-static 3⁄8 in x 50 ft lines rated to 4000 psi.
SmartControl™ sensors. Keep pressure fluctuations under ±1 % for perfect fan patterns.

Upgrade Productivity with OEM Accessories

Graco airless paint sprayer accessories turn the 5900 Lo-Boy into a multi-task powerhouse:

CleanShot™ shut-off valve—kills spitting on soffits when you back-roll.
JetRoller™ combo—spray & roll in one pass; ideal for chase walls.
12–36 in extensions—reach 18 ft ceilings without stilts; color-match collars with graco spray tip guards for instant ID.
LineLazer 3400 gun kit—swap hoses and stripe parking lots without renting a dedicated striper.

Field-Tested Maintenance Roadmap

Daily: Flush with 2 gal clean water or mineral spirits; add three drops TSL to packings.
Every 500 gal: Replace inlet strainer and manifold filter; log hours in BlueLink.
Every 1000 h: Install a new Endurance pump lower; torque gland nut to 50 ft-lb and record in your Graco Paint Sprayers Parts log.
Seasonal: Winterize with Pump Armor® until green fluid appears at the gun; store above 40 °F.

Frequently Asked Questions

Can the 5900 HD Lo-Boy power two guns?: Yes. Install a 0.031 tip on each gun and keep pressure near 2700 psi. Follow a 60-mesh manifold filter to avoid starving the fans.
Is the Lo-Boy weaker than the Hi-Boy?: No—same 1.6 gpm pump and Honda GX160 engine. The Lo-Boy simply rides a lower cart for easier van loading.
Will handheld LP tips fit my 5900 gun?: Absolutely. RAC X LP and FFLP tips are universal across graco handheld sprayers and Contractor PC guns.
How long does a suction tube last?: Typically 5000 gal. Replace sooner if the 8-mesh screen dents or if you see cavitation at priming.

Boost Productivity—Order OEM 5900 HD Parts Today

Add genuine Graco GMAX II 5900 HD Lo-Boy parts—from pump kits and RAC X graco spray tip guards to graco suction tube assemblies and graco airless paint sprayer accessories—to your cart now. With cross-platform compatibility spanning Graco Paint Sprayers Parts from X5 handhelds to 7900 gas rigs, SprayersAndParts keeps your crews spraying, earning, and ahead of deadline—project after project.

Graco GMAX II 5900 HD Lo-Boy Series Parts List

Stay Job-Ready with Long-Life Graco GMAX II 5900 HD Lo-Boy Series Parts