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G Force 1977-1990 B-Body transmission crossmember with mounting hardware
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1977-1990 B-Body crossmember | RCB3-4L80

by G Force Performance Products
SKU RCB3-4L80
$380.00

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Product Information

Description

  • Fits GM B-Body Models: Caprice, Impala, LeSabre, Oldsmobile 88,  Bonneville,  Parisienne,  Catalina.
  • Fits Years: 77-90
  • Fits Transmissions: 4L80E, 4L85E
  • A new transmission mount is recommended. P/N: GMTM.

  • Fits GM B-Body Models: Caprice, Impala, LeSabre, Oldsmobile 88,  Bonneville,  Parisienne,  Catalina.
  • Fits Years: 77-90
  • Fits Transmissions: 4L80E, 4L85E
  • A new transmission mount is recommended. P/N: GMTM.

G Force and our Partner Brands engineer bold solutions that make installation easier without sacrificing quality. Get more support from G Force.

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Our engineers are also car enthusiasts—which makes designing automotive parts second nature. Because we use our products, we know the importance of crafting them with strength and durability. Get more performance from G Force.

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Specifications

Weight: 37 lbs

Shipping Dimensions: 51 × 19 × 6 In

Finish: Black Powder Coated

Mounting Hardware: Included

See the G Force Crossmember Overview for more info.

For vehicles originally equipped with 3/8″ crossmember bolts, open existing holes on the frame to 1/2″. If you prefer to retain 3/8″fasteners, upgrade the installatin hardware to Grade 8 bolts and hardened flat washers.

Some minor contact between the floorplan and the crossmember may occur due to body bushing settling and deterioration, or a bowed floor pan. Usually, this is not a problem. A hydraulic floor jack with a wood cushion will correct a bowed floor.

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

Customer Reviews

Based on 9 reviews
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D
Dominique

Great fit

S
Stevenray Beall
1978 Buick lesabre

I converted this Buick to a SBC and 4l80e transmission. This crossmember fit perfectly

Great to hear the Crossmember is a perfect fit! Thanks for the review and the 5 stars.

D
David

5 stars as it's built really well I bought it for a 1984 Cadillac Fleetwood coupe b body frames soposta be the same as a Caprice ECT frame and chassis wise even though I found out these isn't just going to bolt right in long angle iron on the driver side is to long to slide on top of the frame and make it worse doesn't appear bolts holes are differently not lining up and #1 worst part is it hits the factory drive shaft hoop and factory spot welded mounts for the hoop differently not allowing it to even come close sliding in luckily I haven't got power trains in yet but eventually I'll be seeing if it will work after modification if not all have really good tarp weight also the dual exhaust spots hit the floor I'm planning to run a single turbo ATM so kinda a haha on my part diffently not bolt om for 80-93 Cadillac brougham

We're glad you were happy with the quality. Good luck with your project.

J
Josh Wertz

1977-1990 B-Body crossmember | RCB3-4L80

Thanks for giving us 5 Stars!

A
Andy mills
83’ Buick LeSabre

This crossmember fit like a glove. I was going to fab one up, but I was worried about my angle for the driveshaft. This took all the guesswork out of it, and my 4l80e is sitting pretty. I would highly recommend this product, the welds look great, and it is very, very sturdy. I’m not a guy to write reviews normally, so that should tell you something. If you have a B body, just get this.

Thanks for taking the time to review this Crossmember. Glad you got a perfect fit!

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