Does my new VW Golf need to be broken in? I recently purchased a new Volkswagen Golf Wagon TDI Diesel. The manual states that the oil should be changed every 15,000 km. Synthetic oil is used with this engine. Are there special additives used in the original oil to facilitate the break-in period for this engine – or for that matter, any new engine? If not, I wonder if it might be advantageous to change the oil and filter sooner than recommended. I hope to have this vehicle for a long time.– William
Unless you're regularly racing through the Rockies, you won't need to change your new car's oil earlier than the manual recommends, Volkswagen says.
"We have established our intervals to account for average driving conditions," says Volkswagen Canada spokesman Thomas Tetzlaff. "Should your reader be subjecting his car to extreme conditions, such as frequent stop and starts, then a more frequent oil change interval might be in his best interest."
Traditionally, a new car's oil had to be changed early because it was full of metal bits, and sometimes a washer or two, that had washed out of the new engine.
Tetzlaff says Volkswagen uses synthetic oil straight from the bottle – with no additives, like zinc and phosphorous, to add extra lubrication – for the break-in period.
In fact, Tetzlaff says, new cars don't need to be broken in at all.
"Manufacturing tolerances have reached the point where the modern engine requires no special handling in the first few kilometres," he says.
Changing the oil early won't hurt. If it gives you a little peace of mind, go ahead.
New vehicles used to need a break-in period to seal the engine's piston rings to the cylinder walls. Usually, owners were told in the manual that they shouldn't tow a trailer for at least the first 1,000 km and to avoid long stretches at a constant speed.
Check your manual first for special instructions, but, increasingly, new cars don't have special requirements.
"Engines have changed a ton in the last 20 years," says Greg Buerk, instructor in the school of transportation at the British Columbia Institute of Technology. "Now, your engine's broken in when you get it."
Piston rings seal the cylinder and they rely on combustion gases for that seal to work. They sit in a groove around the piston. When the fuel explodes, the rings get pushed out toward the cylinder wall.
In older engines, they wouldn't fit properly against the cylinder walls right away and would need repeated bursts of acceleration to push them out and burnish the cylinder walls to get the right fit.
"Now they use low tension rings and there's much less friction," he says. "The better finish on the cylinder walls along with the coatings on the rings allows for almost instant break in," Buerk says.
Rebuilt engines are a different story. They still need to be broken in and require initial oil changes at 1,000 km, Buerk says.
Some experts, like Mike Allen at Popular Mechanics, advise breaking in new cars – even if the manual doesn't recommend it.
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