How to Flush Brake Fluid on a Ram 5500 Chassis Cab
A brake fluid flush on a Ram 5500 Chassis Cab renews the hydraulic fluid that transfers pedal pressure to the wheels. It can remove water, corrosion products and debris that contribute to a soft pedal, brake fade or anti-lock braking system (ABS) instability. The job also exposes leaks, so it should be treated as an inspection rather than a quick refill.
Because the 5500 may be used for towing, tipper work or a substantial payload, brake condition has direct road-safety consequences. Use the fluid grade and bleed sequence in the manual for the exact model year and build; production changes mean a generic Ram procedure may be incomplete. Never pour engine oil, hydraulic oil or mineral spirits into the reservoir, and do not mix silicone DOT 5 with ordinary DOT 3 or DOT 4 fluid.
For independent maintenance-product research, MostPicker buying guides provide a broader reference for specifications and supplier options. For a truck carrying trade loads around Sydney, Melbourne or Brisbane, ask the operator about brake fade, pulling or warning lamps before starting.
Confirm the fluid and vehicle specification
Start with the VIN-specific Ram manual and the markings inside the master-cylinder reservoir. Many Australian-delivered examples call for DOT 4 low-viscosity fluid, or DOT 4 LV, but the requirement can vary with manufacture date and brake-system supplier. Right-hand-drive layouts are common locally, while imported chassis may have different brake hardware, so physical wheel position alone is not a reliable guide.
Also inspect all four corners, the master cylinder, flexible hoses and hard lines. Look for wetness, rust-coloured residue, bulging hoses or brake-fluid contamination around the reservoir. A low or fluctuating reservoir level can indicate a leak or worn master-cylinder seals. If the pedal is already soft, trace that fault first; flushing cannot correct a damaged hose, seized caliper or contaminated booster.
Prepare the vehicle and work area
Park on firm, level ground and apply the parking brake. Chock the wheels securely, then loosen the relevant wheel fasteners before lifting the vehicle. Release the park brake only when the manual’s bleeding sequence requires it, commonly for a rear circuit. Keep the ignition off unless the model-year procedure explicitly calls for an engine-running bleed.
Set out a wheel brace, jack stands, the correct bleeders, clear hose, a drain bottle and plenty of absorbent material. Brake fluid damages paint and attacks some plastics, while equipment contaminated with water can ruin the benefit of fresh fluid. Work under good lighting, cap loose openings and take waste fluid to a local workshop or recycling facility that accepts it.
Connect the bleeding equipment
Clean around the reservoir before removing its cap. A plastic bottle makes a simple catch container, but a sealed fluid bottle and correctly sized hose are better because the hose must not introduce air. Fit the hose to each wheel bleeder; some rear circuits terminate at a remote block or junction under the chassis, so locate every outlet rather than assuming there are only four visible nipples.
Keep the master-cylinder reservoir supplied with fresh fluid throughout the job. If it empties, air may enter the circuit and the pedal may travel to the floor. Use light, steady pedal pressure while a helper operates a bleeder; do not hold the pedal hard against the stops. For a broader check of how pressure moves through the lines, this brake hydraulics reference is a secondary aid, with the Ram service information taking precedence.
Flush the brake circuits
Use the manufacturer’s sequence where one is specified. Otherwise, many workshops begin with the farthest outlet and work progressively toward the master cylinder, often starting at the rear and moving diagonally. Open a bleeder only about a quarter-turn, allow fluid to flow, and close it before the stream stops completely. Repeat with slow pedal strokes until the expelled fluid runs clear and is free of bubbles.
Dark fluid or visible debris means more flushing is required, but cleanliness is the criterion rather than a fixed volume. Keep exchanging fluid until each branch delivers clean fluid steadily. Replace the reservoir filter if the manual calls for it, and check that the fluid level remains between the reservoir marks. If a hose, fitting or caliper leaks, stop and repair it rather than washing the area with more fluid.
Refill and purge remaining air
Top up the reservoir with the specified fluid to the level directed by the manual or cap. Some procedures require a brief pump of the master cylinder, an ignition-on cycle, or the engine running while the outlets are opened, especially where the ABS pump supplies pressure. Do not guess between these methods: use the procedure for the vehicle’s braking system, and follow the workshop’s safety measures if the engine must run.
Recheck every outlet until no bubbles emerge and the pedal feels firm without being held up. If the pedal remains low, air is still trapped or a seal is leaking, and the vehicle should not be driven. Close the bleeders to their specified torque, wipe away residue and inspect again after the fluid has settled. The reservoir should sit between MIN and MAX, and the ABS warning lamp should remain off; many systems perform a brief ABS self-check at the next firm stop.
Compare DOT 4 LV fluid choices
The right grade matters because ABS valves can react differently to fluid that is too thin or too viscous when cold. Check the owner’s manual for the named standard and approved specification rather than relying on the colour of the bottle.
| Fluid option | Cold-temperature behaviour | ABS suitability | Main caution |
|---|---|---|---|
| DOT 4 LV | Low viscosity when cold supports controlled fluid movement | Preferred where the manual specifies it | Can cost more and must remain sealed |
| Standard DOT 4 | Moderate cold viscosity | Acceptable only when approved | May not meet a low-temperature specification |
| DOT 3 | Higher viscosity when cold | Suitable only for an explicitly approved system | Not a substitute for DOT 4 LV |
| DOT 5 silicone | Very stable across temperature ranges | Only for a silicone-compatible system | Do not mix with DOT 3, DOT 4 or DOT 4 LV |
Australian retailers and workshops commonly stock DOT 4 LV for modern ABS-equipped vehicles. Local climate influences choice: Melbourne, alpine Tasmania and the southern ACT reward low cold viscosity, while Brisbane’s heat still demands an approved high-temperature fluid. Buying locally from an established auto retailer reduces the risk of old stock. An overseas purchase may also add GST, customs clearance and delivery delays for a small bottle, so the saving may disappear.
Finish with a roadworthy check
After the bleed, road-test the unloaded vehicle only if the pedal is firm, the reservoir is stable and no warning light appears. Listen for pump noise, check that the truck tracks straight and does not pull, and inspect the wheels for moisture. A flush does not restore worn pads or cracked rotors, and poor pedal travel, vibration, fluid leaks or an illuminated ABS lamp means the cause needs further diagnosis.
Record the date, odometer reading, fluid specification and work performed in the service book. That record is particularly valuable for a commercial chassis used on regional routes or carrying a body and tow load through Australia’s varying conditions. The practical takeaway is to use the exact approved fluid, keep the reservoir supplied, bleed every circuit until the pedal is firm, and verify the result before the Ram carries its intended load.