1958-1964 Impala LS Trans Mount Adapters

Putting a late model six-speed or automatic behind the LS in a 1958-1964 Impala? These four BRP adapters let a Cadillac CTS-V or Camaro gearbox sit on a conventional transmission mount. Two cover the TR-6060 family and two cover the GM 6L90E, 8L90E and 10L90E automatics.

4 adapters: 2 manual, 2 automatic
TR-6060 adapters in 3/16 steel
8L90E adapter also takes the 10L90E

Planning tunnel work? The 1958-1964 B-Body LS install guide lists which transmissions need it. For the conversion kit, crossmember and headers, see the 1958-1964 B-Body LS page.

$39.99 Cadillac CTS-V T-56 / standard TR-6060 Trans Mount Adapter

$39.99 MG9 high-torque TR-6060 Trans Mount Adapter

$39.95 Cadillac CTS-V 6L90E Transmission Mount Adapter

1958-1964 Impala transmission mount adapter parts

TR-6060 and CTS-V T-56 manual adapters

Late GM automatic adapters

Related Impala swap pages

What comes with each adapter

The CTS-V T-56 and standard TR-6060 bracket is laser cut, CNC bent and jig welded from 3/16 steel, then powder-coated black. Hardware is included.
The MG9 bracket suits the high-torque TR-6060 that BRP lists behind the LSA engine in the CTS-V. Hardware is included.
The 6L90E piece is for the 2009-2014 CTS-V automatic tailshaft housing.
The 8L90E piece adapts both 8L90E and 10L90E tailshaft housings.

1958-1964 B-Body tunnel and crossmember notes

Expect to modify the transmission tunnel with a T-56, TR-6060, 6L80 or 6L90.
On a T-56, a casting tab on the top driver side, between the bolts, gets cut off to help it clear the tunnel.
BRP suggests test fitting the engine and transmission before you make and weld in the tunnel patch panel. The finished patch fits under the stock carpet.
The transmission crossmember bolts into existing holes in the Impala frame, with a gold preload plate on top of the polyurethane mount.

Tunnel and crossmember notes come from the BRP 1958-1964 B-Body LS install guide. Adapter details come from the product names and BRP product text.

1958-1964 Impala LS transmission mount adapter FAQ

Which adapter do I need for a TR-6060 in my 1958-1964 Impala?

Use the CTS-V T-56 / standard TR-6060 adapter for the regular Camaro gearbox. The MG9 adapter is for the high-torque TR-6060 version BRP lists behind the CTS-V LSA.

Is there an adapter for an 8L90E or 10L90E?

Yes. The 8L90E adapter is made for both the 8L90E and the 10L90E tailshaft housing. The 1958-1964 B-Body guide does not list either gearbox, so check tunnel clearance on your car.

Will a 6L90E need tunnel work in a 1958-1964 B-Body?

The B-Body guide lists the 6L80 and 6L90 among the transmissions that need tunnel modifications in these cars.

Do the automatic adapters work with the BRP crossmember?

BRP says both automatic adapters are to be used with its transmission crossmembers. Its product text for the two TR-6060 adapters does not say.