RCB3-400 1977-1990 B body crossmember

1977-1990 TH400 B body crossmember


Model: RCB3-400

:   1977-1990 GM B-Body Platform

  • Transmissions:  TH400 short tail, 2004R, 700R4 with B-Body Tailshaft Mount.
  • Applicable Vehicles:  Chevrolet Impala, Buick LeSabre, Buick Estate, Oldsmobile Custom Cruiser, Oldsmobile 88, Pontiac Bonneville, Pontiac Parisienne, Pontiac Catalina, Pontiac Laurentian, Pontiac Safari

1977-1990 GM B-Body.  (Caprice, Impala, etc.)


For all you Classic B-Body Builders, we’ve designed a direct bolt-in transmission crossmember to accommodate your 2004R or TH400 short tail transmissions, as well as your 700R4 that has the tailshaft transmission mount.  One crossmember, both transmissions!   This is accommodated by a second set of mounting holes on the crossmember to allow positioning the crossmember in the two different locations.  And this is accomplished while still using the factory crossmember mounting locations.  No drilling, cutting, grinding, or welding!   Simple and complete instructions are included, along with new mounting hardware.  Purchase your polyurethane transmission mount separately part number GMTM.  Utilizes early GM double stud pattern on 1 1/2″ centers.

This crossmember utilizes the same patented G Force design that has made us the stand alone leader in high performance transmission crossmembers.  The large exhaust clearance humps facilitate large diameter exhaust systems, and allow you to tuck it up tight for your slammed and ground hugging build.  Buy yours today!

Important Note:  When considering the popular 700R4, there are two basic transmission mount locations.  One version utilizes a transmission mount directly behind the transmission pan on the transmission case.  With the other version the transmission mount is located further reward and bolts to the tailshaft housing.  It is crucial that you properly determine which mount location your 700R4 has.   This RCB3-400 is designed to accommodate the longer tailshaft mount.  If you have the shorter case mount transmission, you will need to purchase our RCB3-700 crossmember.

Buick LeSabre
Buick Electra/LeSabre Estate
Buick Estate
Chevrolet Caprice
Chevrolet Caprice
Chevrolet Impala
Pontiac Bonneville
Pontiac Catalina/Laurentian
Pontiac Catalina Safari
Chevrolet Caprice
Chevrolet Impala
Oldsmobile 88
Oldsmobile Custom Cruiser

Additional information

Weight 32 lbs
Dimensions 51 × 19 × 7 in
Chevrolet Models


Product Years

Product Years Individual

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