LIFTER(S), Hydraulic, Roller: Installation: Installation

WARNING: This page is about a different variant/trim than selected.

Fig 1: MDS Lifter

Courtesy of CHRYSLER LLC

The Multiple Displacement System (MDS) provides cylinder deactivation during steady speed, low acceleration and shallow grade climbing conditions to increase fuel economy.

CAUTION: Engines equipped with MDS use both standard roller tappets (2) and deactivating roller tappets (1). The deactivating roller tappets must be used in cylinders 1, 4, 6, 7. The deactivating tappets can be identified by the two holes in the side of the tappet body (3), for the latching pins.

CAUTION: The tappets and guide holder assembly must be installed as an assembly and in their original locations or engine damage could result.

Fig 2: Tappet Guide Holder Assembly

Courtesy of CHRYSLER LLC

Lubricate the tappet guide holder (1) and tappets (2).

Fig 3: Rear MDS Lifter Assembly
Courtesy of CHRYSLER LLC

CAUTION: If the tappets and guide holder assembly are to be reused, they must me installed in their original location.
Install the tappet guide holder (2) and tappets.
Tighten the tappet retainer bolt (1) to 12 N.m (9 ft. lbs.).
Install the cylinder head. See Engine/Cylinder Head - Installation
Connect the negative battery cable.
CAUTION: To prevent damage to valve assemblies, do not run the engine above fast idle until all hydraulic tappets have filled with oil and have become quiet.
Start the engine and check for leaks.
Road test the vehicle.