Ensuring Safe and Effective Off-Highway Fluid Changes

Good fleet management means regular fluid and lubricant changes to keep heavy-duty vehicles and off-highway equipment working efficiently and operating at optimum levels. As discussed in Part 1, using high-quality fluids suited to the operating cycle and conditions is crucial.

Mark Brighty, Field Test Engineer, Lubrizol Corporation, whose job involves collecting and analyzing used oil samples for the development of bespoke fluid additive packages continues, discussing fluid change intervals and the practicalities of carrying out these routine tasks.

Service in the field: some tractor transmissions require the oil filter to be changed twice as frequently as the fluid.

Q: How are fluid change intervals correctly determined?

Mark Brighty: Fluid change intervals are generally calculated by the vehicle manufacturer and indicated in the maintenance manuals or on their website according to the fluid type and the running conditions; you need to abide by the recommended intervals or you can void your warranty. A lot of fleet managers still use spreadsheets, but some buy proprietary software packages to identify when changes are due and schedule them. Some manufacturers fit on-board satellite systems linked to a master PC within the fleet owner’s workshop, which can alert the need for a service and send messages to the driver. Some vehicles also have oil condition monitoring sensors, which monitor the life of the fluid. The system then notifies the vehicle driver with a warning message on the dashboard or display system.

Q: What else needs to be done at the same time?

MB: It depends on the vehicle. Some are more technical than others and certain vehicles need to have filter changes more regularly than an oil change. With tractors, you might change the oil in the transmission every 2,000 hours, but you need to change the filter(s) every 1,000 hours, because there may be dirt ingress from the ground and soil it’s been working with, or some debris drawn in through the breather system.

A lot of modern vehicles now need their computer systems reset, though some of the more sophisticated systems know that they’ve had a fluid change done because they can measure the pressure before and after a filter, for instance, with a reduction in pressure to a known value indicating a filter change.

Q: Is changing fluids relatively straightforward these days?

MB: Some vehicles are more labor-intensive than others. On some tractors, you have to take off all the guards underneath and take off the sump tray simply to change the suction filter, but that suction filter is one of the most important things to be done as part of the oil change. There’s a lot of downtime in comparison to a vehicle with just a screw-on external canister. If you need to look at a transmission in a truck or bus, while the oil’s draining you tend to be able to undertake that task at the same time. A truck is relatively straight-forward once you’ve got it over an inspection pit where you can work.

Because some modern equipment is so complex, you need to take it to a specialized service agent, perhaps as part of the purchase agreement. It’s an increasingly professionalized business and you have to use qualified, trained experts with the right equipment to ensure warranty compliance and also for transport law. A lot of big fleet owners have their own workshops with qualified mechanics for minor repairs and fluid changes, but those without their own facilities will generally take their vehicle to the OEM’s workshop.

Q: What about a situation, perhaps a breakdown, where the vehicle can’t be brought back to a workshop?

MB: Ideally, you need to be on a solid, stable, even surface where you can get good access to the vehicle, somewhere where spilled fluid won’t cause a danger to anybody or the environment, and with the correct equipment to contain any fluid when it’s being drained. The last thing you want is a biohazard, where fluid is running into watercourses or into food supply chains. You need to make sure that the vehicle is disengaged from gears and cannot be driven, and that it’s in a safe place, because if you’re working underneath the vehicle, the last thing you want is somebody trying to move it. Confined spaces are very hazardous, and you need to assess the situation dynamically and make sure that it’s safe to undertake that task before commencing any work.

Q: What other general safety procedures do you need to observe?

MB: Health and safety procedures and risk assessments should be in place, and if you don’t follow those you put yourself and others at risk of injury. When working with fluids, I’m going to wear safety boots which have oil-resistant soles, and I’ll wear coveralls to make sure my clothing and my skin and my arms are protected. I also apply barrier cream and I will wear safety gloves and, if possible, I’ll wear a pair of safety gloves inside a bigger pair of rubber gauntlets. The last thing you want is oils on your skin, especially hot oils, because that can leave you with some nasty burns. You should always minimize the risk of skin contact; this will reduce the risk of skin infections, which could lead to severe issues like dermatitis and even cancer. I always wear safety specs, as well, because you don’t want oil splashing into your eyes, and if working under a vehicle I will also wear a bump-cap to stop me from hitting my head on nuts and bolts or pieces of equipment.

Q: What other procedures do you need to follow?

MB: With most vehicles, the manufacturer’s manual will tell you how to undertake the task, especially with off-highway equipment. For instance, with some tractors, it will say that the fluids should be hot. This allows the fluid to be circulated and heated to a point where it can drain out a lot more easily and effectively; by doing that, you should be able to drain as much old fluid out of the system as possible. A hot fluid generally means that the thermostat, which can restrict flow of fluid in the system, has opened to allow all the fluid to circulate.

Q: And how about disposal of used and waste fluids?

MB: You should recycle these properly, disposing of them in the right manner as per the specified routines. You should store the fluid in a suitable container, preferably in a bunded area, which will stop spills or leakage from draining into the watercourses or causing a slip hazard, until you can either get it removed by a specialist contractor or until it can be removed safely. You can’t just put it into an empty plastic bottle – some fluids can have acid levels that can eat through plastic within a few days.

There are a lot of companies now who recycle used oil, even fully recycling it to some extent; they can clean a lot of the used elements out of a high-grade product and make it into another lesser-grade fluid. They can also convert it into fuel oil for burning in heating systems. Obviously, it goes through very rigorous processes. It’s not something you can do yourself, but that’s one way it can be disposed of. Good fleet management entails having procedures for safe and effective disposal of dirty used fluids.