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Fits 1979-1988 Chevrolet Monte Carlo; Transmission Crossmember-G-Body-LS - 12644

Fits 1979-1988 Chevrolet Monte Carlo; Transmission Crossmember-G-Body-LS - 12644

SKU: 12644HKR-1
Regular price $341.95 USD
Regular price Sale price $341.95 USD
Sale Sold out

Making it possible to fit almost any GM transmission into your G-Body alongside an LS or LT, this updated transmission crossmember should be used with an aftermarket urethane transmission mount such as the Hooker Blackheart 71223029HKR or 71223030HKR or equivalent. Due to the unique design geometry of this transmission crossmember, attempts to install it with headers and/or engine mounting plates/brackets other than those developed by HOOKER™ for this application will more than likely not be successful. When used with the related Hooker™ 12643HKR or BHS5179 engine mounting bracket kit, this CAD designed transmission crossmember will replicate the stock small block Chevy engine/transmission inclination angle and eliminate or minimize the need to adjust the rear pinion angle in stock to moderately lowered chassis applications. Depending on the transmission, the following part numbers will be necessary: *No additional adapter needed for TH400/200R4/T-56/Magnum. TH350 Transmissions can reuse the factory transmission crossmember, but the slots in the center of the crossmember will need to be elongated in the forward direction. 12655HKR - 4L60/65/70/75 Transmission Adapter 12656HKR - 4L80/85 Transmission Adapter BHS5181 - 10L80/10L90 Car Transmission Adapter - must be used with BHS5182 (for G-Body) BHS5182 - 6L80/90, 8L45/80/90, 10L80/90 Transmission Adapter BHS5183 - Tremec TKX 5-Speed Transmission Adapter


Features:

  • This LS and LT Swap Crossmember for the GM G-Body has some very minor design updates & has been updated from 12644HKR to part number 12644HKR-1
  • Facilitates installation of a 4L60/4L65/4L70/4L80/TH400/2004R/T56/T56 behind an LS engine in 78-88 GM A/G Body applications (may require add-on bracket, see installation notes)
  • Designed using CAD modeling/FEA analysis for optimal fitment, strength, weight, safety and appearance
  • Welded steel construction
  • Provides an optimized engine/transmission inclination angle that is critical to obtaining suitable U-joint working angles, when installed with Hooker 12643HKR engine mounts
  • Designed in conjunction with other Hooker BlackHeart GM A/G-Body engine swap brackets to provide bolt-in installation of Hooker LS swap manifolds, headers and exhaust systems for this application
  • Provides the highest clearance available for up to 3" dual exhaust system routing

Brand Hooker BlackHeart
Color Black
Emission Code 5
Engine GM Gen III/IV (LS)
Finish Black Powdercoated
Material Steel
Product Type Transmission Crossmember
Sale Category Engine Swap Parts
Transmission 200R4
Transmission 4L60E
Transmission 4L65E
Transmission 4L70E
Transmission 4L75E
Transmission 4L80E
Transmission 4L85E
Transmission T56 GM
Transmission T56 Magnum GM
Transmission TH400
Type of Component Crossmember

Year Make Model Submodel
1979-1988 Chevrolet Monte Carlo Base
1986-1988 Chevrolet Monte Carlo LS
1983-1988 Chevrolet Monte Carlo SS
1978-1988 Oldsmobile Cutlass Calais Base
1988 Oldsmobile Cutlass Calais GT
1988 Oldsmobile Cutlass Calais International
1988 Oldsmobile Cutlass Calais SL
1982-1988 Oldsmobile Cutlass Ciera Base
1982-1988 Oldsmobile Cutlass Ciera Brougham
1988 Oldsmobile Cutlass Ciera International
1982-1988 Oldsmobile Cutlass Ciera LS
1986-1988 Oldsmobile Cutlass Ciera S
1986-1988 Oldsmobile Cutlass Ciera SL
1978-1988 Oldsmobile Cutlass Supreme Base
1988 Oldsmobile Cutlass Supreme Classic
1988 Oldsmobile Cutlass Supreme Classic Brougham
1988 Oldsmobile Cutlass Supreme Indy 500 Pace Car
1988 Oldsmobile Cutlass Supreme International
1988 Oldsmobile Cutlass Supreme SL
1978-1988 Pontiac Grand Prix Base
1984-1988 Pontiac Grand Prix LE
1988 Pontiac Grand Prix SE
1988 Pontiac LeMans Aerocoupe
1988 Pontiac LeMans Aerocoupe YL
1978-1988 Pontiac LeMans Base
1988 Pontiac LeMans SE
1988 Pontiac LeMans Value Leader
1978-1987 Buick Regal Base
1987 Buick Regal GNX
1984-1987 Buick Regal Grand National
1978-1987 Buick Regal Limited
1978-1987 Chevrolet El Camino Base
1978-1987 Chevrolet El Camino SS
1978-1987 GMC Caballero Base
1978-1987 GMC Caballero Diablo
1980-1987 Oldsmobile Cutlass Base
1987 Oldsmobile Cutlass Eurosport
1987 Oldsmobile Cutlass Lujo
1985-1987 Oldsmobile Cutlass Salon
1985-1987 Oldsmobile Cutlass Ciera GT
1978-1987 Oldsmobile Cutlass Salon Base
1987 Oldsmobile Cutlass Supreme 442
1978-1987 Oldsmobile Cutlass Supreme Brougham
1981-1987 Pontiac Grand Prix Brougham
1983-1986 Buick Regal T-Type
1978-1986 Chevrolet El Camino Conquista
1981-1986 GMC Caballero Amarillo
1983-1986 Oldsmobile Cutlass Ciera ES
1985-1986 Oldsmobile Cutlass Ciera Holiday
1978-1986 Oldsmobile Cutlass Salon 442
1978-1986 Pontiac Bonneville Base
1978-1986 Pontiac Bonneville Brougham
1984-1986 Pontiac Bonneville LE
1984-1985 Oldsmobile Cutlass Ciera Cruiser
1984-1985 Oldsmobile Cutlass Ciera Cruiser LS
1981-1985 Oldsmobile Cutlass Supreme LS
1983-1984 Oldsmobile Cutlass Calais Hurst
1982-1983 Buick Regal Estate Wagon
1978-1983 Chevrolet Malibu Classic
1983 Chevrolet Monte Carlo CL
1980-1983 Oldsmobile Cutlass Cruiser Base
1978-1983 Pontiac Grand Prix LJ
1982 Buick Regal Limited Turbo
1978-1982 Buick Regal Sport
1979-1981 Chevrolet El Camino Royal Knight
1978-1981 Chevrolet Malibu Base
1978-1981 Chevrolet Malibu Classic Landau
1978-1981 Chevrolet Monte Carlo Landau
1981 GMC Caballero Conquista
1981 GMC Caballero Royal Knight
1980-1981 Oldsmobile Cutlass Brougham
1980-1981 Oldsmobile Cutlass LS
1981 Oldsmobile Cutlass Supreme
1980-1981 Oldsmobile Cutlass Cruiser Brougham
1978-1981 Pontiac Bonneville Safari
1978-1981 Pontiac LeMans Safari
1978-1980 Chevrolet Malibu Classic Estate
1979-1980 Chevrolet Malibu Classic Sport
1979-1980 Chevrolet Malibu Estate
1979-1980 Chevrolet Malibu Sport
1978-1980 Chevrolet Monte Carlo Sport
1978-1980 GMC Caballero Laredo
1978-1980 Oldsmobile Cutlass Salon Brougham
1978-1980 Pontiac Grand Prix SJ
1979 Chevrolet Malibu Landau
1979 Chevrolet Malibu Police
1978-1979 Oldsmobile Cutlass Vista Cruiser
1979 Oldsmobile Cutlass Vista Cruiser Brougham
1979 Oldsmobile Cutlass Salon Hurst
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Policies and FAQs

Return Policy

We accept returns on products within 30 days of delivery. Return shipping is the responsibility of the buyer unless we, the seller, are at fault.

Fault reasons include but are not limited to:
  • Buyer was shipped the wrong product
  • Buyer was shipped a damaged product
  • The product page had incorrect fitment and the part does not fit the Buyer's vehicle
 
The Buyer will not be refunded outbound shipping unless the Seller (Modern Day Muffler & Brake) is at fault.
 
In cases where the Buyer purchases and ships the return please note that if the Shipper (ex. USPS, FedEx, UPS, etc.) loses the return we will not be able to offer a refund as the Buyer must contact the Shipper and make a claim.
 
All products must be returned in original condition, meaning that the product must not be damaged, installed, or missing pieces/parts. If the product is not in original condition a deduction will be issued of up to 50% of the purchase price of the product.
 
Opened boxes, plastic bags, and other packaging are not considered damage (excluding single use items such as, but not limited to, liquids, software, and other components that cannot be reused/resealed).
 
When we, the seller, are at fault, please Contact Us for a return label, products returned with a shipping label not provided by the seller will not be refunded to the buyer. Please also note that our return labels are issued with the dimensions and weight of the original shipment, if the product is being returned in any box/package besides the original please Contact Us with the dimensions and weight.

Returns must be sent to this address:
Modern Day Muffler & Brake
774 Broad Street
Wadsworth, OH 44281
 
Products returned directly to a manufacturer or the incorrect address may be issued a deduction or denied a refund entirely.
 
If a product was delivered outside the 30 day return window or is no longer in original condition please contact us as we may be able to issue a refund in store credit and/or with a deduction. If this is the case please Contact Us as these situations are handled on a case by case basis.
 
If there are any questions, concerns, or doubts about return eligibility please Contact Us and we would be more than happy to assist you.

This page and policy were last updated: July 14th 2023

FAQs

This is the line that runs from the front of the vehicle to the rear. On most vehicles it connects to a junction then you will have rear axle lines. On a few cars the intermediate lines will connect to the rear wheels. It is recommended to change the axle lines if you are replacing the intermediate lines.

Our kits include all of the solid metal lines for that section of the vehicle.

We are happy to help! Please help us to help you by going to our return form and filling out the form as best as you can in order to request a return.

  • Modern Day stands by our parts and is happy to accept returns within 30 days of purchase. Parts must be in new condition.
  • If a part arrives damaged, or is defective, Please report it to us immediately. So we can handle it for your promptly.

Yes but you will need to order in advance. All of our items are not stocked at our location. So please place your order online and we will notify you when it is ready for pick up.

Unfortunately we cannot offer single lines outside of kits

Yes, all are covered by the manufacturer's standard warranty. Most warranties cover the cost of parts. Any installation or other fees are non-refundable.

Online we accept PayPal and all major Credit Cards. If your are picking an item up we gladly accept cash.

We can only ship to your confirmed address in PayPal or your billing address if you pay with a credit card.

Orders typically Arrive within 3 to 10 days depending if it is a stocked item or something we have manufactured at time of sale.

Yes please send us a message through our custom orders page.

Yes, but items sent out of the continental U.S. may incur additional charges based on their destination

The left and right sides on a vehicle are determined as though you were sitting in the driver's seat. The left is the driver's side, and the right is the passenger's side.

Check it again tomorrow. It takes up to 1 day for the carrier to give status and a delivery date. UPS and FedEx provide delivery dates, USPS usually does not but they take no longer than 5 business days.

Yes! Thank you for your military service!

Still have a question or concern?  Please contact use our contact us form!

Yes! Thank you for your military service!

Warranty Information

Customer service is our top priority and because we value your time and energy we ask you to visit our Contact Us page and reach out so that we may assist you in finding the correct warranty for your product. Please include your name, the name on the order, the order number, and the SKU of the product to ensure the quickest and most accurate response to your inquiry.

Product Notices

*NOTE: Product images may not reflect actual product appeareance.

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