Truck Topics

Keep Your Engine Healthy With Oil Analysis

 

Coolant leaks can be detected and repaired before they corrode your bearings and liners. Other types of problems oil analysis can catch early include faulty or worn injectors, leaking air filters, and problems with pistons, piston rings, valvetrains, etc.

One of the things oil analysis does is test for wear metals, such as iron, copper, silver and chromium. Moving parts that are lubricated by the engine's oil – bearings, lifters, valves, cylinder liners, etc. – can break down. When they do, they release microscopic bits of metal into the oil, which can be detected by oil analysis and lead to a diagnosis of a potential problem. Then you can plan to bring the truck in for repairs at a time that's normally slow for loads or when you were planning to take a vacation anyway.

  Oil analysis sometimes picks up problems that normally wouldn’t start showing symptoms until after the warranty has expired. And oil analysis is important data if you ever have a failure that could be argued as a maintenance issue, which would cause an OEM or other company to reject a warranty claim.     Getting Started   There are several sources for oil analysis programs, including oil companies, filter manufacturers, independent labs and truckstops. If you get your oil changed at a truckstop, quick-lube place or other shop, ask the technician to put some of the drain oil in the bottle provided by the kit. You use a pre-labeled mailer included in the kit to send the sample to the lab.   There are often different levels of kits available. If you’re not extending oil drain intervals, you can probably save some money by not buying a kit that tracks TBN (the ability of the oil to neutralize acids) or TAN (total acid number). The more basic kits track wear metals we well as such items as viscosity, soot levels, additive levels, fuel dilution and coolant contamination.   Some companies offer an “instant” or “5-minute” oil analysis which tests for wear metals, viscosity, fuel contamination, soot, etc.     Choosing A Program   It’s a good idea to use the same company/lab each time you do oil analysis so you can track trends – at least three oil analyses' worth of data. A single oil analysis, while it might spot something like a drastic coolant leak, isn’t going to tell you nearly as much as tracking trends will. Use an oil analysis program that provides a charting/tracking feature to show those trends.   Another feature to look for is whether the service tracks your engine’s performance against typical industry results. If your results are significantly different from the industry average for that particular make and model, the service will let you know.   When choosing a lab, make sure it offers plain-English recommendations in its reports. If you ever decide to change labs, make sure to request your data in an electronic format to transfer to your new lab – this typically won't be offered unless you ask for it.   Most oil analysis programs offer you many choices of how to get your results, including in the mail, by fax, and via the Internet. Choose a lab that will contact you immediately if there's a red-flag result showing a potentially serious condition, instead of waiting for the information to be read in the regular report.   How you (or the technician) take the sample is also important. The engine needs to be warm and should be taken at very similar intervals (typically every oil/filter change). Outside contaminants will skew the results. You may even want to put in a separate oil sampling port to avoid contamination.   Containers must be labeled with the right information, including the sample date, vehicle mileage, number of miles on this oil sample, and identifying information on the vehicle and the technician. Double check you have filled out the report entirely.     New Engines, New Oils   A new oil category, CJ-4, was developed for use with the new 2007-emissions engines. You also can use the new oil in older engines, and in fact it may be all you can find in gallon jugs at truckstops. However, if you switch to the new oil, or if you're switching back and forth between the two, it can throw off your oil analysis results.

The CJ-4 oils are chemically very different from the previous CI-4 Plus oils. For instance, if you used the CJ-4 version of Shell's Rimula oil to top off an engine containing the CI-4 Plus version of Rimula, the oil analysis would suddenly show magnesium and moly. There could be enough moly to set off an erroneous flag on your report indicating possible ring wear.

So if you're going to do oil analysis, it's best to stick with one brand and one API category of oil. If you switch, you'll need to let your lab know. And don't compare the oil analysis of the new oil brand/category to the old one – you'll need to set a new baseline and do several oil analysis checks before you can determine any valid trends with the new oil.

Deborah Lockridge is senior editor for Heavy Duty Trucking and RoadStar magazines and has 17 years of experience covering the trucking industry.