When Do I need to Upgrade my Mustang's Oil Pump Gears?

Oil pump gears (OPGs) failure is when the stock OPGs literally break apart in the engine because of unbalanced harmonics. Oil pump gears are powered by the crankshaft and in high horsepower or high revving applications the stock oil pump gears can fail due to the increased harmonics, or oscillating of the gear from the added power and revolutions of the crankshaft. 

This type of failure can cause an engine to be completely destroyed, leaving you in search of a new engine, something that can be avoided for a few hundred dollars in parts and a few hundred dollars in labor.

While 3-valve and 4-valve 4.6 motors have seen some issues with oil pump gear failure, the 4-valve 5.0L coyote motor in 2011 Mustangs has been the main victim of OPG failure. Earlier model Mustangs were not as prone to this failure because it takes a lot of power and a high amount of revs to get them to break, something that wasn’t as easy to achieve as it has been with newer Mustangs. 

As mentioned earlier, part of the problem of oil pump gear failure is from the engine having unbalanced harmonics from over revving. Before the coyote 5.0L motor came out and started dominating the competition, high revving Ford V8’s weren’t really a thing. The stock redline on a coyote motor is 7,000 RPM and 7,800 RPM on a Boss 302 Mustang; add in a supercharger to the equation and you have a recipe for OPG failure.

Stock Mustang oil pump gears are made from a brittle powdered metal which are fine in stock and mild bolt-on applications, but when pushed have trouble holding up with the added stress of drastically increased horsepower. Part of the reason the issue with oil pump gears was never discovered by Ford is because their factory stress-tests never pushed into the range of factors that would cause OPGs to fail; it wasn’t until the aftermarket got a hold of the Mustang until the issue became apparent.

Aftermarket Mustang oil pump gears are constructed from billet steel and CNC machined for a precise fit. When buying aftermarket oil pump gears, you’ll want to go with the more trusted, well-known brands available and not the shoddy, fly-by-night alternatives because they need to be expertly machined in order to hold up.

You need to add oil pump gears to your Mustang when you:

• reach around 650 RWHP
• are modding your Mustang and already have the engine out
• are adding cams, intakes, and other mods to increase the rev ceiling

If you are doing a mild bolt-on build, meaning an exhaust, intake, tune, etc, then you will not need oil pump gears. However, if you are adding a supercharger, shooting for over 600 RWHP, or adding a bunch of mods like camshafts, intake manifolds, cylinder heads, etc. than you will want to add OPG's to your Mustang to avoid damaging the engine from the added power and increased engine revving.