Corvette Hood, Hatch or Trunk Lid Strut Replacement

by Hib Halverson

Gas-filled lift struts make loading Corvette Coupes for long road trips easy. Image: Sandy Rubel.

General Motors calls them “struts”. They are also known as “lift supports”, “lift assist struts”, “lift struts”, “gas struts” or “gas springs.” Regardless of the nomenclature, we Corvetters take them for granted, but without these devices, servicing Corvette engines and loading luggage might be more difficult.

This math art shows the guts of a typical lift strut. Image: Stabilus

Lift supports contain pressurized nitrogen gas in closed cylinders fitted with a sliding piston. Attached to the piston is a rod, at least as long as the cylinder, which enables the strut to vary in length. The gas pressure is sealed by a guide/seal assembly at the rod end of the strut. Inside the strut, potential energy is stored pneumatically and resists external force applied parallel to the direction of piston movement.

These struts allow lifting, positioning, lowering and safely counterbalancing weights. In automotive applications, that weight is usually that of horizontal body panels that open and close, such as hoods and deck lids. Before lift struts were invented, such heavy body parts were held open by powerful, difficult-to-replace, and ugly-looking springs or extendable supports that could be locked when open.

Shown are key components that connect the hatch, hood, or trunk lid to the body structure. Not shown are the notched ends of the spring steel clips that lock the strut on the ball pivot.

Corvette lift struts are simple, less costly and weigh less than any of those previous devices which supported open hoods or trunk lids. They have ball socket ends attached to metal ball pivots on both the body structure and the hood, hatch or trunk lid. The strut ends lock to the pivot balls with curved, spring steel retaining clips

The hood and hatch strut assortment that are available from Zip Products for 2005-2013 C6s.

Corvettes have used these struts since 1982 to support C3 Collector Edition, C4, C5, C6 and C7 Coupe rear hatches. They are also used to support C5, C6 and C7 hoods and trunk lids. On C8s, gas struts are used to support “frunk” lids, engine lift gates, and convertible, rear compartment lids.

Typically, a strut’s service life in automotive use is about five years. Most struts malfunction due to loss of gas pressure caused by the failure of the piston rod seal. Time, frequency of operation, extreme temperature changes and environmental influences may affect the piston rod seal’s service life. Other, but uncommon problems, can be physical damage to the piston rod or failure of the mounting hardware.

If replacement of a strut is necessary, Zip Products sells lift supports for C3 CE hatches; C4, C5, C6, and C7 hatches; C5, C6, and C7, hoods; and C5, C6, and C7 trunk lids.

Pictured is a C6 hatch lift strut.

Zip’s Rear Hatch Lift Struts include the following:

Pictured is a C7 hood lift strut.

Zip’s Hood Lift Assist Struts include the following:

Pictured is a C5 trunk lid lift strut.

Zip’s Trunk/Deck Lid Assist Struts include the following:

The imagery for this article was created during a hatch and hood strut replacement on a C6 Coupe, but the procedure for changing the lift struts is similar for all applications.

Step 1: Corvette rear hatches are heavy. During a strut replacement, either have an assistant hold the hatch open or install a temporary support device.

01: Some hood and all hatch strut replacements require either an assistant to hold the hood or hatch open while you replace the struts or you also can use a temporary support device adjustable for length, a fixed support of the correct length to prop the hood or hatch open while the struts are changed will also work. Trunk strut replacements can be accomplished by holding the lid open by hand. It is best to change struts one at a time rather than both at once.

Step 2: A variety of tools can be used to retract the ends of the steel clip and free the strut’s ball socket from the ball pivot. L to R: small diameter pin punch, center punch, awl, narrow blade screwdriver, short narrow blade screwdriver.

02: To remove the lift supports you need to unlock the curved, spring steel clips holding them to ball pivots. To unlock the clips, depending on the design of the strut’s ball-socket ends, you need either a pointed tool such as a small diameter pin punch, a pointed punch or an awl, or a narrow blade screwdriver or sometimes, even both tools.

03: In some cases, where access to the ends of the lift strut is restricted, such as the lower end of a C7 hood strut, you may need to first remove some parts blocking that access and once you can access the end of the strut, you may need a spring clip removal tool that is short enough to fit in the available space.

Step 4a: This strut socket has an electrical connection for a rear window defogger. Struts for hatches with defoggers will have a connection on each end.
Step 4b: The connectors on the struts snap into place and may fit very tightly. A strong grip with your fingers and a hard pull on the connector body may be necessary for removal.

04: Some hatch struts also serve as a patch for electricity to get from the car’s rear defogger wiring to the defogger which is bonded to the inside of the hatch glass.

Step 5a: Release of this type of strut end requires a pointed tool.
Step 5b: Put the tip of your sharp tool in the hole adjacent to the top of the spring clip. Pry the clip away from the ball socket end.

05: If there is a small round hole under the top of the steel band, use the tip of your sharp tool to pry up on the spring clip.

Step 6a: Release of this type of ball socket requires a narrow blade screwdriver.
Step 6b: If the clip on the ball socket has a slot rather than a hole, use the narrow blade screwdriver to pry the clip up and away from the socket.

06: If there is a narrow slot under the top of the steel band, use the narrow blade screwdriver while gently pulling or prying on the ball socket to remove it from the ball.

Step 7: As you pry the clip away from the ball socket and pull on the struts, the end of the strut will pop loose from the ball pivot.

07: While you are holding the spring clip up, pull on the end of the strut to free it from the ball socket.

08: Typically balls last the life of the vehicle, so just wipe the ball clean of any grease or dirt. Inspect the sockets on the new lift support to see if the manufacturer put a small dab of grease inside the socket. If there is no grease, using a toothpick, you’ll have to put a small dab of wheel-bearing grease or equivalent on the top of each ball.

Step 9a: Generally, installation of the new strut is quite easy, as was replacing struts on this C6 Coupe’s hatch.
Step 9b: Once the ball socket is resting on the top of the ball pivot, push firmly on the socket and it will snap into place.

09: Install the new lift struts by positioning each ball socket over the top of its ball, then pushing it onto the ball. You should feel and hear a “pop” as the spring band snaps over the ball locking the strut in place.

Corvette Hood, Hatch or Trunk Lid Strut Replacement

Source: Zip Corvette Parts
8067 Fast Lane | Mechanicsville, VA 23111 | (800) 962-9632

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One Comment

  1. Judi maske

    I need to know what the part is inside 07 convertible vette trunk. Right on middle in back like under window or where top goes. Little but rustetyankbyou

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