Hydraulic oil

With hydraulic oil for car lifts, the lift decides, not the label

Which oil goes in a car lift? Whatever the lift manufacturer specifies, which for car lifts is usually an HLP oil of viscosity grade 32 or 46. Here you'll find which oil goes with Weber-Werke and Wematik, plus the rules for topping up, mixing and changing. Spindle lifts don't need hydraulic oil.

Hydraulic oil is the pressure medium in hydraulic Car lifts: the pump in the hydraulic power unit pushes it from the reservoir into the cylinders that raise the vehicle. At the same time, it lubricates the pump and valves and protects the hydraulics against wear and corrosion. Car lifts usually run on HLP oils, mineral oils with additives against wear and corrosion. For you, that means the oil is part of the lift's design, not a consumable you pick to taste.

• Two viscosity grades, two lift families. At 40 °C, HLP 32 sits between 28.8 and 35.2 mm²/s, HLP 46 between 41.4 and 50.6 mm²/s. Weber-Werke specifies HLP 32 for its lifts, Wematik its HPL46 in grade 46. We stock the matching oil for both families.
• The fill quantity depends on the lift type. According to Weber-Werke, the KHB-1000E short-stroke scissor lift takes about 6 litres of HLP 32, the DSH-3500 double scissor about 20 litres. We stock 5 and 10 litre containers; the exact quantity for your lift is in the manual.
• Used oil goes back free of charge. For both oils, the product page describes free take-back of the purchased quantity as used oil for proper disposal, with the return point at the respective distributor. At an oil change, yearly or about every 2 years depending on the lift manufacturer, the whole fill comes out.

Detailing1's tip from the shop: Topping up follows a fixed order: first find out the grade, then pick up the can. The manual and delivery note tell you which oil the lift had from the factory. Only top up with the same specification, never a different viscosity grade on top. On a used lift with unknown contents, change the oil completely including a tank clean instead of mixing. That costs you one full fill once and saves you the question of what's actually in the tank every time something plays up later.

In the lift, hydraulic oil carries the pressure that raises the car

In hydraulic car lifts, the oil transmits the pump's force to the cylinders, lubricates the pump and valves on the way and protects the hydraulics against wear and corrosion.

That applies to every lift with hydraulic cylinders: 2-post lifts with electro-hydraulic drive, scissor lifts from short-stroke to double scissor, and hydraulic single-post models. On these, the oil is the part of the machine that carries the load from the pump to under the vehicle. If it's low or the grade is wrong, the function suffers first and, in the long run, the hydraulics themselves.

Electromechanical spindle lifts are different. There, one motor per column lifts via spindle and load nut, and there's no hydraulic oil in the lifting system. That's how the Weber models C-2.30 and C-2.40 among the 2-post lifts and the C-1.25 among the 1-post lifts work. If you own one of those, you need nothing from this page; spindle and load nut are lubricated to the manufacturer's spec.

Day to day, the oil gets noticed when something sticks: the lift rises empty but not with a car on it, one side lags, or lowering drags on. In user forums, the oil quickly gets the blame. It's one possible cause alongside valves, adjustment and air in the system. So fault-finding belongs in the operating manual, not in the next can of oil.

People also search for hydraulic oil for log splitters, tractors, bike brakes and jacks. Each of those follows its own manufacturer's spec. The oils in this category are positioned for car lifts; whether one of them suits a trolley jack is decided by its manual, not by how close they sit on the shelf.

HLP 32 or HLP 46: the number describes the viscosity

The number after HLP is the viscosity grade: HLP 32 flows more easily at 40 °C, HLP 46 is thicker, and both are mineral oils with additives against wear and corrosion.

Viscosity is how thick an oil is, measured in square millimetres per second at 40 °C. Grade 32 covers 28.8 to 35.2 mm²/s, grade 46 runs from 41.4 to 50.6 mm²/s. Put simply: by nominal value, the 46 is a good 40 percent thicker than the 32 and flows more sluggishly through lines and valves. In practice, a lift's pump, valves and lowering speed are matched to one of these viscosities, which is why the manufacturer specifies the grade.

HLP is the common designation for mineral-oil-based hydraulic fluid with additives against wear and corrosion. For its oil, Weber also lists water and air separation and ageing resistance. In plain terms, trapped air and moisture separate from the oil more easily, and it stays stable for longer. For you, that means less foam in the pump and an oil that ages more slowly.

Wematik writes its oil as HPL46. That's the product name; the specification on the product page is that of a grade 46 HLP oil. The grade is called HLP 46, the product Wematik HPL46, and it's the same oil. That's how manual and can match up.

There are also HVLP oils. Their viscosity index is improved, so their viscosity changes less with temperature. That can make sense in systems with big temperature swings. Even so, an HVLP only replaces a specified HLP oil if the lift manufacturer approves it, and we don't stock HVLP.

The lift sets the grade, not the shelf

Which oil belongs in a car lift is in the lift manufacturer's manual, and the specs differ noticeably even between brands of the same lift type.

Two scissor lifts, two grades: Weber-Werke specifies HLP 32 for the short-stroke scissor Weber-Werke Scherenhebebühne "KHB-1000E" Weber-Profi-Serie, while scissor lift maker Kroemer specifies HLP 46 for its models. Twin Busch specifies HLP 32 for all its lifts, Wematik recommends HPL46 for its lifts. So if you buy by lift type alone, it's easy to end up with the wrong grade. The lift's brand is a quicker guide than its shape.

In the cold, manufacturer specs diverge. MAHA calls for a thinner oil at permanent ambient temperatures below 15 °C, Nussbaum names an ATF below 5 °C, and other manufacturers allow HLP only. So there's no general winter rule.

In one forum thread, an owner asks whether a 22 instead of the 32 helps against the cold; the replies advise against it and point to the setting in the manual. If your lift stands in an unheated space, ask your lift's manufacturer for approval before you deviate from the spec.

Engine oil, gear oil and brake fluid are no substitute. They're built for other jobs, manuals for hydraulic equipment explicitly rule them out, and the wrong fluid puts the seals at risk. In forums you occasionally read that viscosity doesn't matter and engine oil will do. The manufacturer specs say the opposite, and they decide whether the lift raises and lowers the way it was signed off.

On mixing, the sources contradict each other: one lubricant dealer considers it harmless, another advises against it for different viscosities. Lift manufacturer MAHA only allows topping up with the same specification, and Rotary rules out mixing bio and mineral oil. The safe line follows on its own: top up with the same grade, and if in doubt, change it completely.

The oil level is only right with the lift fully lowered

You read the oil level of a hydraulic car lift at the reservoir with the lift fully lowered, because in the raised position part of the oil is sitting in the cylinders.

That's how lift manufacturers Nussbaum and Rotary describe it. The German statutory accident insurance recommends checking the oil level of hydraulic lifts weekly; for private use, that's a good benchmark. The daily visual check before lifting for any oil leaks is covered on the Car lifts page along with the other check points.

The change follows the manufacturer's interval. Twin Busch names a yearly change in which the tank is drained and cleaned and the oil and oil filter are replaced; Nussbaum also says yearly, Stertil-Koni about every 2 years. So the oil change belongs in the maintenance schedule, not only in the repair.

Water in the oil, condensation for example, speeds up ageing and corrosion. Rotary gives a limit of no more than 2 percent water content. For you, that means: if the lift stands in a damp or unheated space, better not stretch the manufacturer's change interval.

After filling, the hydraulics are bled according to the operating manual, in user reports by raising and lowering several times. Bleeding means driving trapped air out of lines and cylinders. Air compresses, oil hardly does. How you notice it: a lift with air in the system judders, or one side lags.

At first commissioning, oil quantity, limit switches and lowering speed go together: forum reports on a Weber short-stroke scissor and a Wematik scissor describe the lowering speed needing adjustment and a lowering valve being closed from the factory. If your new lift seems sluggish on day one or won't lower, that can be part of the setup and needn't be a fault.

The steps for checking and topping up are summed up in the instructions below this description. Repairs to valves or cylinders aren't part of that; they remain a job for customer service or a competent person following the manufacturer's spec.

Weber-Werke HLP-32 for Weber, Wematik HPL46 for Wematik

The range assigns each oil to a lift family: the Weber-Werke HLP-32 to Weber lifts, the Wematik HPL46 to Wematik lifts, both with wear protection according to the product page.

The Weber-Werke Hydrauliköl "HLP-32" comes in a 10-litre container and, according to the product page, is intended for Weber lifts. Weber-Werke lists zinc-containing anti-wear additives for it. It suits the hydraulic models in the Weber-Werke range, such as the KHB-1000E short-stroke scissor. It's not meant for the same brand's spindle lifts, because they lift without hydraulics.

The Wematik Hydrauliköl "HPL46" comes in 5 and 10 litres. The product page describes it as suitable for all Wematik lifts and lists wear protection and ageing resistance. According to the manufacturer, the Wematik Scherenhebebühne "Miami Plus" Basic has a 5-litre tank, and according to the product title it comes with 5 litres of oil.

Twin Busch also specifies HLP 32 for its lifts. What decides is the specification in the manual, not the brand on the can. If the manual says HLP 32 with no further restriction, an oil of the same specification will do; if the manufacturer requires a specific product, its spec applies.

Quantity and stock are covered by the subcategory Hydraulic oil in canisters; this page is about the grade.

Some car lifts already come with hydraulic oil

The buying decision on oil follows the lift: manufacturer and model set the grade, the manual the quantity, and what's in the box shows whether you need to buy any at all.

The quantity depends on the lift. A double scissor takes several times the fill of a short-stroke scissor, so the figure in the manual counts for more than any rule of thumb. For a full change, allow for the whole fill; for topping up, only the amount up to the mark. If the lift stands in the cold, check with the manufacturer first whether the spec applies there too.

The lesson we take from our orders: the HPL46 ended up several times in the same basket as the Miami Plus, which according to its title already comes with 5 litres of oil, and one return was for exactly that reason. So check the box and delivery note first, then the manual, and only then order.