G Force RCG-4L80K Transmission Crossmember,1978-1983 G-Body, GM-4

This generation of vehicle is prone to body bushing compression, even with some southern vehicles. If the floor pan is too close to allow installation, it may be necessary to replace the body bushings. Some customers have reported that with slight interference instances, they have been able to gently lift the floor pan with the assist of a floor jack and a wood cushion, thus providing the required clearance for installation. On all 78-88 G body crossmembers, the passenger side hump is the taller of the two, and on some installations, it is necessary to remove the catalytic converter heat shield from the passenger side floor pan.

1984 models and the implementation of the 2004R transmission required positioning the crossmember further to the rear of the vehicle. This is evidenced by 2 sets of frame holes for the crossmember on the driver side of the vehicle. G force has developed the frame extension (p/n FE1-00) to duplicate this longer frame on the early generation vehicles. RCG-400k is pre-packaged with the frame extension.

Note: while this change was platform wide beginning in 1984, some 1983 Hurst Olds are known to have the 2004R transmission and thus the longer frame rail.

• Fits 1978-1983 G-Body
• Includes frame extension

Since different transmissions can share the same overall lengths as well as other measurements, they can also share some transmission crossmembers. G-Force has grouped the transmissions together that can share the same crossmember.

This Crossmember fits the GM-4 Transmission Group:

• Hydra-Matic 4L80 transmission
• Hydra-Matic 4L80-E transmission
• Hydra-Matic 4L85 transmission
• Hydra-Matic 4L85-E transmission