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B&M Transpak - GM TH400/375 Transmissions - 20228

B&M Transpak - GM TH400/375 Transmissions - 20228

SKU: 20228
Regular price $128.95 USD
Regular price Sale price $128.95 USD
Sale Sold out

Overview:

The B&M® Transpak is the next step up from the B&M Shift Improver kit. It has all the features in the Shift Improver kit, plus it provides additional driver manual control (GM TH-400, 350, Ford C-6 and Chrysler Torqueflite only). B&M® Transpak™ kit for 1965-1987 GM TH400/375 automatic transmissions. Most stock automatic transmissions won't downshift into low gear above 15 mph, and automatically upshift at a predetermined speed no matter what gear you're in. With the Transpak, you can downshift at any speed, and you can hold the transmission in first gear to any speed that you want! This is an asset when you've got a modified engine, and you want additional RPMs, or you're towing a trailer or driving heavy loads downhill. Stage 1. Heavy Duty is for street rods, normal passenger vehicles or other heavy duty use. Firmer shift feel but not harsh. Improves transmission performance and life dramatically without loss of comfort and offers normal automatic operation when in Drive. Stage 2 is for Hi-Performance street use. Essentially the same as Heavy Duty mode except shifts are much quicker. Retains full automatic features and standard shift points with selector in Drive.

Features:

  • Recalibrate's GM TH400 Automatic Transmissions
  • Full Manual Control on Most Transmissions
  • Over 65 Years of B&M Quality
  • Improves Transmission Life
  • Optimum Performance
  • Firmer Shifts

Year Make Model Submodel Engine Size
1970 - 1974 Chevrolet G30 Van
1969 - 1975 Chevrolet Nova
1965 - 1967 Buick Special
1965 - 1983 Cadillac Commercial Chassis
1965 - 1969 Pontiac Tempest
1966 - 1972 Buick Sportwagon
1966 - 1968 Pontiac Tempest Custom
1967 - 1984 Chevrolet C10 Suburban
1967 - 1986 Chevrolet C20 Suburban
1967 - 1984 Chevrolet K10 Suburban
1967 - 1986 Chevrolet K20 Suburban
1967 - 1974 GMC K15/K1500 Suburban
1967 - 1970 Pontiac Executive
1968 - 1970 Pontiac Tempest Base
1968 Pontiac Tempest Safari
1970 - 1974 GMC G35/G3500 Van
1967 - 1974 GMC K25/K2500 Suburban
1967 - 1974 GMC C25/C2500 Suburban
1975 - 1978 GMC C15
1979 - 1986 GMC C1500
1975 - 1978 GMC C15 Suburban
1979 - 1984 GMC C1500 Suburban
1975 - 1978 GMC C25
1979 - 1986 GMC C2500
1975 - 1978 GMC C25 Suburban
1979 - 1986 GMC C2500 Suburban
1975 - 1978 GMC C35
1979 - 1986 GMC C3500
1977 - 1978 GMC G15
1979 - 1987 GMC G1500
1975 - 1978 GMC G25
1979 - 1987 GMC G2500
1975 - 1978 GMC G35
1966 - 1974 Chevrolet K10 Pickup
1966 - 1974 Chevrolet K20 Pickup
1969 - 1974 Chevrolet K30 Pickup
1969 Chevrolet Kingswood Base
1971 Chevrolet Kingswood Estate
1972 Chevrolet Kingswood
1973 - 1974 Chevrolet Malibu Base
1970 - 1975 Chevrolet Monte Carlo
1965 - 1984 Cadillac Fleetwood
1969 - 1973 GMC P35/P3500 Van
1974 GMC P35/P3500 Van Base
1971 - 1975 GMC Sprint
1965 - 1971 Oldsmobile 442
1965 Oldsmobile 98 Base
1966 - 1980 Oldsmobile 98
1968 - 1974 GMC C35/C3500 Pickup
1969 - 1974 GMC G15/G1500 Van
1969 - 1974 GMC G25/G2500 Van
1970 - 1987 GMC Jimmy
1976 - 1978 Cadillac Eldorado Cabriolet
1976 - 1978 Cadillac Eldorado Biarritz
1976 Cadillac Eldorado Bicentenial Edition
1976 - 1978 Cadillac Eldorado Base
1965 - 1979 Cadillac Eldorado
1974 - 1983 Cadillac Fleetwood Base
1980 - 1981 Cadillac Fleetwood Brougham
1980 - 1981 Cadillac Fleetwood Brougham d'Elegance
1980 - 1983 Cadillac Fleetwood Formal
1987 Cadillac Brougham
1975 - 1982 Checker Marathon
1975 Buick Century Base
1975 Buick Century Custom
1975 Buick Century Luxus
1973 - 1977 Buick Century
1965 - 1981 Buick Electra
1970 - 1981 Buick Estate Wagon
1965 - 1981 Buick LeSabre
1973 - 1977 Buick Regal
1965 - 1978 Buick Riviera
1978 Buick Skyhawk
1965 - 1976 Cadillac Calais
1965 - 1981 Cadillac DeVille
1970 - 1972 Buick GS
1968 - 1974 Buick LeSabre Base
1966 - 1974 Chevrolet C20 Pickup
1966 - 1974 Chevrolet C30 Pickup
1967 - 1975 Chevrolet Camaro
1975 - 1987 Chevrolet P20
1973 Chevrolet Camaro Base
1973 Chevrolet Camaro RS
1973 Chevrolet Camaro LT
1966 - 1975 Chevrolet Caprice
1965 - 1972 Chevrolet Chevelle Base
1965 Chevrolet Chevelle Deluxe
1966 - 1971 Chevrolet Chevelle
1972 Chevrolet Chevelle SS
1966 - 1967 Chevrolet Chevy II Base
1967 Chevrolet Chevy II Nova SS
1967 - 1977 Chevrolet Corvette
1965 - 1975 Chevrolet El Camino
1969 - 1974 Chevrolet G10 Van
1969 - 1974 Chevrolet G20 Van
1965 - 1975 Chevrolet Impala
1966 - 1973 Pontiac GTO
1965 - 1975 Pontiac LeMans
1965 - 1966 Pontiac Star Chief
1971 - 1974 Pontiac Ventura
1975 - 1976 Pontiac Grand Safari
1979 - 1987 GMC P2500
1975 - 1978 GMC P35
1979 - 1987 GMC P3500
1987 GMC R1500
1987 GMC R2500
1987 GMC R2500 Suburban
1987 GMC R3500
1987 GMC V1500
1987 GMC V2500
1987 GMC V2500 Suburban
1987 GMC V3500
1971 - 1980 Oldsmobile Custom Cruiser
1968 - 1975 Oldsmobile Cutlass
1975 Oldsmobile Cutlass Salon
1975 Oldsmobile Cutlass Supreme
1968 - 1980 Oldsmobile Delta 88
1978 Oldsmobile Toronado
1968 - 1975 Oldsmobile Vista Cruiser
1965 - 1977 Pontiac Bonneville
1968 - 1977 Pontiac Catalina
1975 Pontiac Firebird Trans Am
1969 - 1977 Pontiac Firebird
1973 - 1975 Pontiac Grand Am
1975 Pontiac Grand LeMans
1976 - 1977 Pontiac Grand LeMans Base
1977 Pontiac Grand LeMans Safari
1965 - 1977 Pontiac Grand Prix
1971 - 1975 Pontiac Grandville
1976 - 1977 Pontiac LeMans Base
1976 - 1977 Pontiac LeMans Sport
1977 Pontiac LeMans Safari
1973 Buick Apollo
1971 - 1973 Buick Centurion
1965 - 1967 Buick Gran Sport
1965 - 1972 Buick Skylark
1968 - 1974 GMC C15/C1500 Pickup
1968 - 1974 GMC C15/C1500 Suburban
1967 - 1974 GMC C25/C2500 Pickup
1965 - 1967 Pontiac Catalina Base
1966 Pontiac Catalina 2+2
1966 - 1967 Pontiac Catalina Safari
1975 - 1987 Chevrolet P30
1987 Chevrolet R10
1988 Chevrolet R20 Custom Deluxe
1987 Chevrolet R20
1987 Chevrolet R20 Suburban
1987 Chevrolet R30
1987 Chevrolet V10
1987 Chevrolet V20
1987 Chevrolet V20 Suburban
1987 Chevrolet V30
1965 - 1967 Chevrolet P10 Series
1969 - 1974 Chevrolet P10 Van
1965 - 1967 Chevrolet P20 Series
1969 - 1974 Chevrolet P20 Van
1965 - 1967 Chevrolet P30 Series
1969 - 1974 Chevrolet P30 Van
1979 - 1986 GMC G3500
1981 - 1987 GMC G3500 Rally
1981 - 1987 GMC G3500 Rally STX
1981 - 1987 GMC G3500 Vandura
1981 - 1987 GMC G3500 Magnavan
1981 - 1987 GMC G3500 Rally Camper Special
1981 - 1987 GMC G3500 Vandura Special
1987 - 1988 GMC G3500 Rally Custom
1977 - 1978 GMC K15
1979 - 1986 GMC K1500
1977 - 1978 GMC K15 Suburban
1979 - 1984 GMC K1500 Suburban
1975 - 1978 GMC K25
1979 - 1986 GMC K2500
1975 - 1978 GMC K25 Suburban
1979 - 1986 GMC K2500 Suburban
1977 - 1978 GMC K35
1979 - 1986 GMC K3500
1976 - 1978 GMC P15
1979 - 1980 GMC P1500
1975 - 1978 GMC P25
1966 Chevrolet Suburban
1969 - 1972 Chevrolet Townsman
1974 Chevrolet Vega
1969 - 1987 Chevrolet Blazer
1969 - 1972 Chevrolet Brookwood
1966 - 1974 Chevrolet C10 Pickup
1967 Oldsmobile Cutlass Turnpike Cruiser
1967 - 1968 Oldsmobile Delmont 88
1976 - 1978 Cadillac Seville
1965 - 1975 Chevrolet Bel Air
1977 - 1986 Chevrolet K5 Blazer
1975 - 1986 Chevrolet C10
1975 - 1986 Chevrolet C20
1975 - 1986 Chevrolet C30
1974 Cadillac Fleetwood 75
1974 Cadillac Fleetwood 60 Special
1965 - 1972 Chevrolet Biscayne
1966 - 1974 GMC K15/K1500 Pickup
1967 - 1974 GMC K25/K2500 Pickup
1968 - 1974 GMC K35/K3500 Pickup
1969 - 1974 GMC P15/P1500 Van
1969 - 1974 GMC P25/P2500 Van
1977 - 1987 Chevrolet G10
1975 - 1987 Chevrolet G20
1975 - 1987 Chevrolet G30
1977 - 1986 Chevrolet K10
1983 Chevrolet K10 Custom
1983 Chevrolet K10 Scottsdale
1983 Chevrolet K10 Silverado
1975 - 1986 Chevrolet K20
1977 - 1986 Chevrolet K30
1975 Chevrolet Laguna
1975 Chevrolet Malibu
1976 - 1980 Chevrolet P10
1967 - 1968 Pontiac Firebird Base
1967 Pontiac Firebird HO
1967 - 1968 Pontiac Firebird Sprint
1967 - 1968 Pontiac Firebird 400
1968 Pontiac Firebird 350
1965 - 1966 Oldsmobile Dynamic 88
1965 - 1972 Oldsmobile F85
1966 Oldsmobile F85 Base
1966 Oldsmobile F85 Deluxe
1966 Oldsmobile Jetstar 88
1973 - 1974 Oldsmobile Omega
1965 - 1966 Oldsmobile Starfire
1969 Buick Skylark Base
1965 - 1970 Buick Wildcat
1968 Buick Wildcat Base

Automotive Item Grade High Performance
Brand B&M
California Proposition 65 Chemical Name Cadmium and cadmium compounds
California Proposition 65 Required Yes
Emission Code 5
Gasket Included Yes
Instructions Included Yes
Manual Control Partial
Product Type Automatic Transmission Valve Body Kit
Warning California Proposition 65
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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.