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G Force G Body Crossmember


Welcome back. I'm Stephanie with G Force Performance.

Today, Jordan and I will be discussing our G-Body G Force crossmembers. Some examples of G Bodies are El Camino, Monte Carlo, and Cutlass—ranging in model years from 1978 through 1988.

There are some things to look for when you are choosing your G-Body crossmember. In 1978, GM began staggering the bolt hole pattern on the frame. The G Force crossmember is designed to accommodate this.

So Jordan, what are some other details we need to know when choosing our crossmember?

Well, the G-Body was broken up into an early and a late model classification. In 78, G Bodies were equipped with a shorter three-speed transmission and the frames were built accordingly.

They started putting a 2004R transmission in their vehicles which was a longer four-speed and they had to add a length to the driver's side to accommodate for this longer transmission. So, if you're trying to install a late-model transmission in the early model G-Body it may be necessary to use our Graham extension.

Well, this isn't always the case though. Some 83 Hurst Olds had a 2004R from the factory and the frame was built accordingly. It was a little bit longer on the driver side to accommodate. Also, some 84 El Caminos had a shorter frame. So, for this reason it's important to check for these differences in your vehicle to make sure you're getting the right parts.

Now let's move on to the installation of the G-Body.

On the G-Body crossmember the passenger side hump is the taller of the two. Also, the exhaust clearance humps are closed on the top and they are open on the bottom.

Now Jordan, can they give us some more tips on the install of the crossmember?

Yeah. All of our crossmembers are installed with the G Force decal facing the rear of the vehicle. The G Bodies, specifically, you might need to remove the catalytic converter heat shield from the passenger side of the car. These generation vehicles also are prone to body bushing compression. So, if you have any kind of interference installing the crossmember you might need to replace your body bushings.

Some customers have had luck using a floor jack and a wood cushion to slightly lift the floor up just to get the crossmember in. As stated before, if you want to install a newer four-speed transmission into your early G-Body you will need a frame extension.

Now this frame extension adds the needed length for the longer transmission on the driver side. It's an easy install. All you have to do is drill a couple holes and use the provided hardware.

So now what if our installer is also doing an engine swap?

Well, the G-Body crossmember allows for a little bit of movement forward or rearward, but if the drivetrain has moved more than the allowance of the crossmember you might want to check out our website for adjustable transmission mount.

Thanks Jordan and thank you for joining us today. We hope this information will help you with your project.

Be sure to visit us at to view our full line of crossmembers and performance products.


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