Tools› Engine-Related

GForce

Transmission Mock-Up Block

$234.99

SKU: GF-MUT-4L80

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

Beginner — under 30 min

Overview

The GForce GF-MUT-4L80 is a transmission mock-up block designed for accurate mounting and yoke placement. This lightweight, disassembled tool allows for easy positioning by hand, eliminating the need to handle a heavy transmission during fitment and fabrication. Its durable steel construction resists welding heat, enabling custom crossmember fabrication close to the block.
Show original supplier description
The GForce Swap Block® Transmission Mock Up Block (GF-MUT-4L80) is a patent-pending tool engineered to provide precise transmission mounting and yoke positions for 4L80/4L80E transmissions. This unique, lightweight design comes disassembled, simplifying shipping and storage. It is specifically designed to aid in the placement of 4L80/4L80E transmissions found in 1991-2013, 3/4 ton trucks and vans. This mock-up block simplifies the installation process, saving time, money, and improving safety by allowing for manual positioning without the need to physically lift a heavy transmission. The durable steel construction is built to withstand welding heat, allowing for custom crossmembers to be fabricated in close proximity to the mock-up, unlike foam alternatives. Assembly instructions are available for download and are similar to the LS engine mock-up block assembly, utilizing the same patent-pending tab-and-slot system. Mounting hardware is not included with this product.

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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Available on iOS & Android

Specifications

BrandGForce
Part NumberGF-MUT-4L80
CategoryTools

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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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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