63-87 Chevy & GMC C10/C20/C30/Blazer/Suburban Transmission Crossmember (Bolt-On)

63-87 Transmission Crossmember - #120-5117

If you own a Chevy or GMC truck from 1963 to 1987, the GSI Machine & Fabrication universal transmission crossmember is the best thing you can buy. This crossmember gives you the flexibility and strength you need for modern high-performance builds, whether you're doing a simple transmission swap or a full frame-off restoration.

This crossmember was first designed as a key part of our famous front suspension kits, but now it can be bought on its own for builders who need precision. With the universal design, you can perfectly line up your drivetrain and set your pinion angle exactly where you want it.

The GSI Advantage

• Total Adjustability: Fine-tune transmission height and pinion angles to eliminate driveline vibration.

• High-Clearance Design: The crossmember can be flipped upside down for a higher tuck—ideal for lowered or "slammed" trucks needing maximum ground clearance.

• Superior Construction: Fabricated from 1.500" DIA DOM tubing and 3/16" ASTM A1011 hot-rolled steel for a high strength-to-weight ratio.

• Premium Finish: Every unit comes sandblasted and powder-coated in a durable semi-gloss black to resist corrosion and road debris.

• Precision Fit: Includes custom GSI shims to account for factory frame variations, ensuring a tight, secure installation.

Technical Specifications

• Length: 33-5/8 Inches (End-to-End)

• Weight: 9 lbs

• Material: Heavy-Duty DOM Tubing & 3/16" Plate Steel

• Hardware: Grade 8 Yellow Zinc Plated Bolts, Washers, & Nylock Nuts included.

• Origin: Proudly Made in the USA.

Vehicle Fitment

• 1963–1987 Chevrolet: C10, C20, C30, Suburban, K5 Blazer

• 1963–1987 GMC: C1500, C2500, C3500, Suburban, Jimmy

Transmission Compatibility

This crossmember has a "Mark and Drill" universal design, so it works with almost all popular GM-style mounts, such as

• Powerglide, TH350, TH400, 200-4R, 700R4, 4L60/E, 4L70E, 4L80E, and 6L80E are all automatic.

• Muncie/Saginaw 3 and 4 speeds, Borg Warner T-5, NV3500, NV4500, Tremec TKO/TKX, and T-56 6-speed are all covered in the manual.

What’s Included

• (1) Transmission Crossmember (Black Powder Coated)

• (2) Logo Shim Mounts (Black Powder Coated)
  

• (4) 3/8 x 1.25 Bolts 

• (8) 3/8 Flat Washers
  

• (4) 3/8 Nylock Nuts

Questions? Contact Us

(480) 940 1806 – Local
1 (877) 951-1890 – Toll Free

At GSI Machine & Fabrication, we offer a one-year warranty on all manufactured parts, covering defects upon inspection. However, we are not liable for personal or property damages resulting from misuse of our products. Note that warranties for non-manufactured parts, such as shocks or ball joints, must be handled directly with the part’s manufacturer.

Orders may be canceled before shipment, except for special-order and custom items, such as chassis products and air ride suspension. Refunds for eligible returned items will exclude shipping costs and may incur additional fees. For cancellations or issues with orders, contact our customer support at 1 (877) 951-1890 or sales@gsimfab.com.

Customers are responsible for all customs fees, duties, and taxes on international orders. Once your package is shipped, we are not liable for damage, theft, or loss during transit. Please inspect your delivery promptly and report any issues within 48 hours. For international shipments, local policies may cause delays, and additional documentation may be required. Always ensure shipping details are accurate to avoid additional costs.