G Body Crossmember | 78–88 700R4 & 4L60E Fitment — G Force Performance Products
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Product Information

Description

G Body Crossmember for 700R4, 4L60E, and T5 Swaps

  • Fits Models: GM RWD G-Body; Malibu, Monte Carlo, El Camino, Cutlass, Grand Prix, Regal, Century, LeMans, Caballero, Bonneville
  • Fits Years: 78-88
  • Fits Transmissions: 700R4 Case Mount, 4L60, 4L60E, 4L65E, T5, TKO, TKX, 2WD-AR5.
  • If you are looking for improved performance check out our lighter weight, next generation of this transmission crossmember, RCGNG-700BLK. What is a lightweight crossmember? Find out here.
  • We recommend a polyurethane transmission mount. The GMTM is sold separately.
  • NOTE:  Some 700R4 transmissions have options for both a case mount and a tailshaft mount. Some utilize only a tailshaft mount. For a tailshaft mount in your 1978-1983 GM G-Body you will require P/N: RCG-700TSK. For a tailshaft mount in your 1984-1988 GM G-Body you will require P/N: RCG-700TS.      
  • NOTE:  In some cases, an RCG-700 installed with a T5 may require a custom transmission mount to maintain proper drive line angle. 
Boss Hog Torque Converters recommended for this application:

G Body Crossmember for 700R4, 4L60E, and T5 Swaps

  • Fits Models: GM RWD G-Body; Malibu, Monte Carlo, El Camino, Cutlass, Grand Prix, Regal, Century, LeMans, Caballero, Bonneville
  • Fits Years: 78-88
  • Fits Transmissions: 700R4 Case Mount, 4L60, 4L60E, 4L65E, T5, TKO, TKX, 2WD-AR5.
  • If you are looking for improved performance check out our lighter weight, next generation of this transmission crossmember, RCGNG-700BLK. What is a lightweight crossmember? Find out here.
  • We recommend a polyurethane transmission mount. The GMTM is sold separately.
  • NOTE:  Some 700R4 transmissions have options for both a case mount and a tailshaft mount. Some utilize only a tailshaft mount. For a tailshaft mount in your 1978-1983 GM G-Body you will require P/N: RCG-700TSK. For a tailshaft mount in your 1984-1988 GM G-Body you will require P/N: RCG-700TS.      
  • NOTE:  In some cases, an RCG-700 installed with a T5 may require a custom transmission mount to maintain proper drive line angle. 
Boss Hog Torque Converters recommended for this application:


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Specifications

Weight: 33 lbs

Shipping Dimensions: 51 × 11 × 6 In

Finish: Black Powder Coated

Mounting Hardware: Included

See the G Force Crossmember Overview for more info.

This transmission crossmember has been redesigned to accept the double slot bolt pattern of standard transmission mounts.

On some installations, it is necessary to remove the catalytic converter heat shield from the passenger side floor pan.

For all 78-88 G body crossmembers the passenger side hump is the taller of the two.

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 instances where there is slight interference they have been able to gently lift the floor pan with the assistance of a floor jack and a wood cushion to create enough clearance for installation.

This crossmember is installed so that the exhaust clearance humps are closed on the top and open on the bottom.See the G Force Crossmember Overview for more info.

This crossmember is installed with the G Force label facing the rear of the vehicle. However, another determining feature is the crossmember center tube which has a 1/2″ drain slot that is positioned on the bottom and on the passenger side next to the hump weldment.

This crossmember is installed so that the exhaust clearance humps are closed on the top and open on the bottom.

To use the provided 7/16″ hardware it is necessary to enlarge holes in your frame rails with a 1/2″ drill. If you choose to use the stock size 3/8″ hardware, it is strongly recommended to use new Grade #8 fasteners to compensate.

Discover more about the G Force Crossmember product line on these pages-

Customer Project Photos