Tech Tips: GM Reprogramming Oil Life Monitors
On April 5, 2013, General Motors reprogrammed 800,000 oil life monitors on 2010-2012 Chevrolet Equinox, GMC Terrain, Buick La Crosse and Buick Regal vehicles. These models have the 2.4L LAF and LEA four-cylinder engines.
Dealerships will reprogram the oil life monitor for free until February 28, 2015. They will do this service for free, even if the model is out of warranty.
What’s wrong, and why is GM being so kind?
First of all, the four-cylinder engines run very rough. So a chain links the crankshaft and balances the shaft to smooth out the engine. It looks like a bicycle chain, and it’s not the timing chain or belt. As the chain wears, the engine could run roughly and become noisy.
What’s causing this?
Years ago, ISAC moved the ZDDP spec in motor oil to 0.08 percent. ZDDP coats the internal engine parts and protects them from wear. However, the OEMs said ZDDP was causing catalytic converter failure.
With the engine drain intervals and the use of ethanol fuel, the ZDDP coating is removed faster. The best way to slow this process is to change the motor oil several times a year.
So, if you get one of these models in and the engine is noisy and a little rough, tell the customer about this situation up front, before you do anything. Also, be sure to note it on the invoice.
A question that I have is, since OEMs purchase a lot of parts from the same suppliers, if one OEM is having this problem with their four-cylinder engine, then other OEMs must be in the same boat, are they not?
Be careful, and good luck.
Technical Tips is written by Scotti Lee, Ph.D., former operator of Oil Change Express in New Castle, Delaware, and current principal in the California-based Oil Changers chain of lube shops. Lee may be reached at 302.764.7329.
Technical Tips is a forum for fast lube operators and suppliers to share practical solutions to problems common throughout the industry. National Oil & Lube News is not responsible for the accuracy and reliability of submitted tips, and NOLN does not assume liability resulting from their use. Email tips to: firstname.lastname@example.org