I have a 2008 Toyota FJ Cruiser, and it’s been a fantastic vehicle for my wife and me - we’ve put about 350,000 miles on this beauty.

One day, I tried to roll down the passenger-side window and got nothing. I checked the fuse and wiring, and everything looked fine, so I assumed that after so many miles of going up and down, the window motor had finally burned out.

I ordered a replacement motor from RockAuto. After some time - and a nicked knuckle or two - I got it installed. I double-checked that all the wiring was connected, turned on the ignition, and tried the window. Nothing. I went over everything again. Still nothing.

Frustrated, I finally gave in and took it to a shop to see if I had installed it incorrectly or damaged something. Later, they called to say they had the window working. When I asked what I’d done wrong, they told me they had simply pressed the window lock button. I had the window locked the entire time! I can never show my face at that shop again.

Bob in Colorado

When doing an engine oil change, I first clear off space on the workbench and set out the new oil bottle(s), oil filter and any related supplies (gaskets, drain plug...) and tools (oil filter wrench, socket...). As work progresses, the old oil filter and empty oil bottle(s) are put on the workbench. That way if I ever get distracted, I can look at the workbench and quickly see what work still needs to be done. When the job is finished, there should be an old oil filter, empty oil bottle(s) and all the tools sitting on the workbench.

If all this careful planning falls apart for some reason (oil spill, bottles thrown away too soon, workbench rolls down the driveway...), I can still use the oil dipstick to verify that I put new oil in the engine. The dipstick reading may not be accurate because the new oil has not circulated through the engine yet, but at least I can be sure I will not be starting a completely dry (no oil) engine.

Some newer engines (Mercedes-Benz, RAM/Jeep...) do not have a dipstick to fall back on. Avoiding distractions and mistakes becomes even more important for the DIYer, but imagine how hard it is for a professional shop that pulls new oil from big storage tanks rather than bottles and has dozens of different oil filters on the shelf. Did we put new oil in that truck sitting in bay three yet...?

Why not just partially turn the ignition key/button and look at the electronic oil level display on the instrument panel? Unfortunately, the sensors and software do not update the oil level immediately. Instead, they kind of do it like a human would: run the engine for awhile while the vehicle is parked on a flat surface so the oil has time to warm up and circulate throughout the engine. Only then does the computer record an oil level value.

Checking Oil Without Dipstick

This is a quote from the owners manual for the 2025 Ram 1500 (equipped with the 3.0L inline six): "Because the oil level is automatically detected only when the engine has been off and restarted (after four minutes), the system cannot immediately detect a sudden drop in oil level while driving (for example, if the oil pan starts to leak due to damage during an off-road event)."

The owners manual for the 2024 Mercedes-Benz C-Class says the computer will only record the oil level after: "The engine has been warmed up. The vehicle is parked on a level surface. The engine is running at idle speed. The hood is closed. Determining the engine oil level can take up to 30 minutes with a normal driving style and even longer with an active driving style."

When you first start these dipstickless engines after an oil change, the electronic display is likely showing an old oil level measured before the vehicle was driven into the garage. You will not know the new oil level until the engine has run awhile. "Awhile" is always too long to run an engine if it has no oil in it. (I am not sure what "active driving style" means, but a dry engine will certainly not survive 30 minutes of it.)

To reliably verify there is oil in a dipstickless engine, you would have to loosen the oil drain plug and see if new oil starts dripping out. Peace of mind is worth a little wasted oil. As with any engine, also watch for the oil pressure warning light to quickly turn off after the engine is started. The oil pressure warning light will go out if there is oil circulating, and it is separate from the oil level system.

At RockAuto.com look under "Engine" (both for specific vehicles and in the "Tools & Universal Parts" tab) to find the oil, filter, parts and tools you need for successful oil changes.

Tom Taylor,
RockAuto.com

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