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Adding a JLT Performance Oil Separator to a 5.7L Hemi

A Quick and Easy Solution

Words and photos by Chris Holley

The oil separator installation took less than 30 minutes to complete. A ratchet and 13mm socket, a Phillips screw driver, and some lube was all that was necessary for the installation.


How many 5.7L Hemi engines has DaimlerChrysler, Chrysler LLC, and now, FCA sold since its 2003 Ram truck introduction? Adding in the Durangos, 300s, Magnums, Chargers, Grand Cherokees, Commanders, Aspens, and Challengers, the number must easily exceed a million engines in the last 16+ years. During that time span, several companies have expanded their business, and new companies have joined the industry to meet the aftermarket demand of the new Hemi owners.

With a large selection of aftermarket parts, we checked the internet for an oil separator for our 2006 Dodge Charger chassis dyno mule. One of the companies that has greatly expanded in the last decade is JLT Performance, and they had a perfect oil separator for the 2005-2018 5.7L Hemi. The JLT 3.0 oil separator (part no. 3061P, MSRP $139.00) could be easily installed without modifications to the Hemi, and it would fit neatly under our engine cover.


What is the purpose of the oil separator? As a result of an internal combustion engine operating through its four cycles, some cylinder pressure escapes around the piston rings and into the crankcase. To combat this, the positive crankcase ventilation (PCV) valve was introduced to extend oil life, minimize engine sludging, and control oil leakage. Since the early 1960s, the PCVs have been found on every engine, and they work great. The concern with our Charger, which sees plenty of chassis dyno time when testing products, is we experience a bit of oil entering the intake manifold during the back-to-back-to-back wide-open-throttle (WOT) runs. The oil separator would be fitted between the PCV valve outlet and the inlet to the intake manifold in an attempt to capture oil that may escape past the factory PCV oil separator.

The upper housing of the oil separator has a honeycomb screen that holds the oil vapor escaping from the PCV valve. Once enough oil vapor collects, it drops into the cup (top right). Only oil-free air flows into the intake manifold.


The JLT Performance oil separator has a fine honeycomb mesh stainless-steel screen that will trap fine oil vapors, and once enough trapped oil vapor collects, it drops into the base cup. With the oil collected in the cup, it is too heavy to return to the passing air flow and into the intake manifold.


The base cup can hold up to 3 oz of fluid and has a knurled external grip, which allows the cup to be threaded off when the trapped oil needs to be poured out. Once the cup is threaded in place, an O-ring seals the unit and prevents leaks. Servicing of the cup can be performed with every oil change with a maximum of 10,000 miles between services. Unfortunately, at this time, the oil separator is not CARB (California Air Resource Board) exempt. It is currently not legal for sale or use in California or any state that has adopted the California emission standards.


When our oil separator showed up, there was the knurled cup attached to the upper housing with the honeycomb oil separator and external hose fittings. Additionally, there was a bracket with a bolt to attach to the cylinder head, two screws to attach the upper housing to the bracket, and lastly, two hoses of different length.

This 5.7L Hemi is a replacement engine with just under 40K miles on it. It was replaced when the 2006 Police Package Charger was still “Protecting and Serving.” The Charger is often run on a Mustang chassis dyno to test new bolt-on components.

To install the JLT 3.0 oil separator, we needed to remove the Hemi engine cover. The cover is easily removed by pulling upward, which releases the four connecting pins.


To install the JLT Performance oil separator, we popped the hood of the Charger and pulled off the decorative engine cover. With access to the PCV system, we pulled the hose that extended from the PCV valve outlet to the intake manifold inlet. The hose was set aside, so it could be used in the future should the oil separator be removed. To mount the oil separator bracket, there was a threaded bolt hole in the passenger side cylinder head just below the valve cover gasket surface. We quickly chased the hole with a tap to confirm the hole’s threads were free from debris. With the threads cleaned, we lined up the hole on the bracket to the bolt hole of the cylinder head, threaded in the supplied bolt, adjusted the bracket, and tightened the bolt.

The hose (screw driver) between the PCV and the intake manifold would be removed for the installation of the oil separator. We stored the hose, so we could reuse it in the future if, for some reason, we removed the oil separator.

The PCV hose slipped off of the PCV nipple and pulled from the intake manifold. There are no hose clamps to hold the hose in place, so it is very easy to remove.

This single bolt hole on the passenger cylinder head (found on all the 5.7L Hemis) is the anchor point for the new oil separator bracket. Before the bracket installation, we ensured the threads were clean and in good shape.

The bracket was lined up with the hole, and the bolt was snugged, so we could perform our final adjustment. Once properly aligned, we worked around the EGR tube to tighten the mounting bolt.


We unthreaded the tank cup from the upper housing, and the shorter of the two supplied hoses was slipped onto the left most 90° fitting on the housing (this fitting is level with the housing top). The long hose was pushed onto the 90° fitting on the right side of the housing (the fitting is at a 45° upward angle compared to the housing top). The other end of each of the hoses was internally lubed with some light oil to facilitate the installation of the hoses onto the 5.7L. Even with the lubrication, the hoses were a challenge to install. The longer hose was routed to the PCV valve, and the shorter hose was directed to the intake manifold.

The hoses included with the oil separator required some lubrication to slip onto the PCV nipple and the intake manifold. Even with the lube, it was a challenge to slip each hose onto the engine.

Even with the nipple and the hose lubricated, we worked hard to slip the hose onto the PCV housing. We took our time when installing the hose. Eventually, the hose slipped into place.

The same situation occurred with the other hose on the intake manifold. We took our time, so we would not damage the intake manifold. The two hoses took a large portion of the total installation time.

Two screws secured the upper housing to the bracket. Notice the routing of the hoses. JLT made sure the 90° fittings on the oil separator were properly angled to ensure an interference-free installation of the hoses.


The two small screws were run through the upper bracket support that had been previously installed to the cylinder head. The screws were tightened into the upper housing of the oil separator. To install the tank cup, we had to remove the intake air temp (IAT) sensor connector and slip the cup under the exhaust gas recirculation (EGR) valve tube. Once the cup was worked around the EGR tube, we threaded the cup onto the housing, reattached the IAT connector, and fitted the engine cover back onto the engine.

The bracket fit between the EGR tube, cylinder head, and intake manifold. It fit so well, it looked like it was a factory designed bracket.

To thread the oil separator cup onto the upper housing, we had to disconnect the intake air temperature connector and work around the EGR tube. With a little finesse, the cup was threaded onto the upper housing.

This angle provides the best view of the completed installation. The oil separator fits so well, it looks like the factory designed and installed it.

The oil separator fit under the engine cover without the need for modifications. Sadly, when the hood is open, the beautiful JLT oil separator will never be seen by the average onlookers, but we will know it is there, and it is effectively doing its job.


The oil separator was a simple installation that we completed in less than 30 minutes. Its solid billet construction looks great. If at some time in the future we need to go back to the factory parts, we can easily remove the oil separator and reinstall the factory hose.


Since the installation, we have driven the Charger on the street and continued to perform WOT tests on the chassis dyno. At the first oil change since the installation, the oil separator had collected some oil that would have found its way into the intake, so it appears to be doing its job.



JLT Performance Inc.

1008 Executive Blvd.

Chesapeake, VA 23320

Phone: 757-335-1940

Email: info@JLTtruecoldair.com



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