Drivetrain› Automatic Transmissions and Components

GForce

4L80E/4L85E Transmission Crossmember Kit

$375.00

SKU: RCG-4L80K

In Stock
In Stock
Ships by Sep 9
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The GForce RCG-4L80K is a transmission crossmember designed for GM RWD G-Body vehicles from 1978-1983. It is specifically engineered to accommodate 4L80E and 4L85E transmissions.

This kit includes a frame extension, GF-FE100, to replicate the longer frame found on these early generation vehicles. The crossmember features a black powder-coated finish and comes with the necessary mounting hardware.
Show original supplier description
The GForce RCG-4L80K is a transmission crossmember kit designed for 1978-1983 GM RWD G-Body vehicles, including models like the Malibu, Monte Carlo, El Camino, Cutlass, Grand Prix, Regal, Century, LeMans, Caballero, and Bonneville. This kit is engineered to facilitate the installation of 4L80E and 4L85E transmissions. This specific kit includes the GF-FE100 frame extension, which is necessary to duplicate the longer frame found on earlier G-Body vehicles. The crossmember itself is constructed with a durable black powder-coated finish and comes with all the required mounting hardware for a complete installation. Installation notes indicate that some 1983 Hurst Olds models may already have the longer frame rail, negating the need for the included GF-FE100 frame extension. Conversely, some 1984 El Caminos may retain the earlier frame design and still require the GF-FE100 extension. Additionally, it is recommended to use a polyurethane transmission mount, which is sold separately. Some installations may require the removal of the catalytic converter heat shield from the passenger side floor pan. For mounting, it is necessary to enlarge frame rail holes to 1/2″ if using the provided 7/16″ hardware, or use new Grade #8 fasteners if retaining the stock 3/8″ hardware.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandGForce
Part NumberRCG-4L80K
CategoryDrivetrain

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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