SKU: 40906880020

1984-1988 Chevrolet Monte Carlo Crossmember TH400 / 2004R RCG-400

Sale price$154.29 Regular price$171.43
Save 10%

Pay in installments of $42.86 with ShopPay, AfterPay and Klarna

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Aug 20 - Aug 25

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

Description

1984-1988 Chevrolet Monte Carlo Crossmember TH400 / 2004R RCG-400Overview: Transmission Crossmember for 84 88 G Body (RWD) RCG 400 Fits Models: GM RWD G Body; Monte Carlo, El Camino, Cutlass Supreme, Grand Prix, Regal, Caballero, Bonneville Fits Years: 1984 1988 Fits Transmissions: TH400, 2004R If you are looking for improved performance check out our lighter weight, next generation of this crossmember, RCG 400NG BLK. We recommend a polyurethane transmission mount. The ParT Number GMTM is sold separately. The

Overview:

Transmission Crossmember for 84-88 G Body (RWD) - RCG-400

  • Fits Models: GM RWD G-Body; Monte Carlo, El Camino, Cutlass Supreme, Grand Prix, Regal, Caballero, Bonneville
  • Fits Years: 1984-1988
  • Fits Transmissions: TH400, 2004R
  • If you are looking for improved performance check out our lighter weight, next generation of this crossmember, RCG-400NG-BLK.
  • We recommend a polyurethane transmission mount. The ParT Number GMTM is sold separately.
  • The primary frame change on the 1978-1988 generation of GM G-Body vehicles begins with 1984 models and the implementation of the 2004R transmission which required positioning the crossmember further to the rear of the vehicle. This is evidenced by two sets of frame holes for the crossmember on the driver side of the vehicle.
  • Note: Some 1983 Hurst Olds are known to have the 2004R transmission and thus the longer frame rail which does not require the GF-FE100 frame extension that is included in this Kit. Some 1984 El Caminos retained the early frames and do require an GF-FE100 frame extension to run this crossmember.

Applications:

  • 1987 Buick GNX
  • 1984-1987 Buick Grand National
  • 1984-1987 Buick Regal
  • 1984-1987 Chevrolet El Camino
  • 1984-1988 Chevrolet Monte Carlo
  • 1984-1987 GMC Caballero
  • 1985-1987 Oldsmobile 442
  • 1984-1987 Oldsmobile Cutlass Supreme
  • 1988 Oldsmobile Cutlass Supreme Classic
  • 1984-1986 Pontiac Bonneville
  • 1984-1987 Pontiac Grand Prix
  • Transmission: Turbo-Hydramatic 400 (TH400 / THM400) or THM200-4R (2004R)
  • Crossmember

Fitment Notes:

  • The RCG-400 is bolted to the rear set of frame holes on the driver’s side frame rail.
  • 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
  • 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.
  • Some 1983 Hurst Olds are known to have the 2004R transmission and thus the longer frame rail which does not require the GF-FE100 frame extension that is included in this Kit. Some 1984 El Caminos retained the early frames and do require an GF-FE100 frame extension to run this crossmember.
  • 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.

Specs:

  • Brand: G Force
  • Color: Black
  • Country of Origin: United States
  • Finish: Powder Coated
  • Material: Steel
  • Mounting Hardware: Included
  • Weight: 32 lb
  • Part Number: RCG-400


Interchange:

  • RCG-400-GFPP
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 40906880020

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.7 ★★★★★
Based on 18 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
A
Verified Purchase
Amazon Customer
Battle Creek, US
★★★★★ 3
Eaten by my Thighs
Color: 04-multicolour (4-pack), Size: X-Large
I wanted to love them. Sadly they have let me down. Pros: natural breathable fabric , super soft and comfortable, cotton panty gussets for feminine health and panty liners will stick!! Yay:). And the colors! They are great! But here’s the Con. And it’s the con of all cons. THEY RIDE UP!! Eaten by my thighs. I’m 5’6” and in the general area of 175. I fluctuate depending on how many times I visit the bakery! :) I don’t have a thigh gap but it is not a super tight thigh squeeze. I seldom have thigh climb but these do. I tried two different sizes to see if that made a difference. Nope. I was miserable at a recent theme park in these. I was wearing long heavy dresses and it was quite awkward to yank these legs down non stop. They feel amazing and they have all the requirements 1. Soft 2. Comfortable and stretches with you 3. Breathable with nice thin fabric. Not bulky 4. Natural fibers 5. Great colors If you are a person that is not blessed with Thunder Thighs, please order these. They are great! I wear them at home and to locations that I will not be doing a lot of walking at. I have washed them so many times and they look like new still.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 4, 2025
A
Verified Purchase
Ally Cat
Whiting, US
★★★★★ 5
Best Boxer Briefs for Women!
Color: 09-multicolour (4-pack), Size: Large
I rarely give 5⭐️’s but these deserve it! Hands down, the most comfortable material, stitching, waistband, moisture wicking and overall comfort. They sit right beneath my bellybutton, they wash and dry well and they’re sturdy. I have tried 3 styles and these are the best.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 7, 2026
A
Verified Purchase
Amazon Customer
Lake Worth, US
★★★★★ 5
Super comfortable! Great for layering under loose, cheeky shorts. Colors amazing!
Color: Multicolor B (5-pack), Size: Small
I specifically got these to wear under some loose shorts I got from Amazon (5 Pack Modal Lounge Shorts) so my cheeks don't show when bending over, and the pop of color looks amazing anyway! I have a 27" waist and 37.25" hips, and size Small works perfect for me. I love how these shorts have a classic underwear lining that a pad would sit perfectly on, whereas the longer boxer style ones of this same brand do not have that classic panty liner style crotch. The material is uniquely thick, stretchy, and thin/breezy all at once! To be honest, I am not opposed to wearing these straight up as shorts to work out it. They look like cute booty shorts and no one would know they're technically underwear. Plus when you buy a 5 pack like this, you're getting an amazing price whereas most athletic shorts are priced at $20 per pair or more, and they're not made with ANY natural materials like these BambooCool shorts are. I like them!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 24, 2026
A
Verified Purchase
Amy Landi
Fort Morgan, US
★★★★★ 5
Best Sleep Shorts EVER ♥️
Color: Multicolor a (5-pack), Size: Medium
Love, love, LOVE these bamboo BoyShorts! I wear them for sleeping because they’re incredibly light, soft and comfortable while still having a great liner. They fit to my body while not feeling tight, snug or restrictive. Soooo comfortable. I’m 5’8” 145 lbs and went with Medium. ♥️
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 6, 2026
K
Verified Purchase
kaylaj13
Massapequa, US
★★★★★ 5
Amazing fit!!!
Color: Multicolor a (5-pack), Size: Large
These are quite literally the best underwear I have ever worn. I am going to replace all of my underwear with just these. I got the shorter boy shorts cut and they are amazing. These let my body be the shape that my body is, no squeezing or tight waist band. I feel so normal and comfortable in them, they’re breathable and soft!! I absolutely love them after so much trial and error with underwear I finally found the ones!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 20, 2026

recommand products