Old frames with riveted or no crossmembers can flex due to elongation of the rivet holes. This issue becomes more pronounced when adding higher horsepower engines and performance suspension, leading to increased frame flex. Progressive Automotive offers specially designed X-members with transmission cross members that help eliminate the flex caused by age, increased power and performance suspensions.

Our X-members are designed for either automatic and manual transmissions. Each X-member includes a steel, bolt-in transmission mount, allowing for easy removal from the bottom without the need to pull the motor from the vehicle.

Top and bottom side tubes are formed as one piece, as opposed to welded square or rectangular tubes. This design approach eliminates stress cracks that can occur, ensuring greater strength and durability.

Their X-members are also designed to allow for the passage of 3″ exhaust with a half-inch clearance. It’s worth noting that the availability of space for exhaust may be limited when underfloor pedal assemblies are used.

If your vehicle isn’t listed in their offerings, contact us for our X-member Tech sheet.

These crossmembers are manufactured in our shop in Baltimore, Ohio, U.S.A. to insure quality and craftsmanship.

Boxing Plates for C-channel style frame rails can be found here:

Frame rails reinforcements for Chevrolet car top hat frame can be found here:

Underfloor brake and Hydraulic Clutch/Brake Pedal Assemblies can be found here:

Optional items are listed at the bottom of this page

*Tubular X-member kits, include:

(2) X-member sides, assembled

(1) Steel trans. Mount with mounting hardware

(1) Rear connector

and either

(1) Straight connector & Drop connector

(1) K- connector

Connector tube are coped (notched) for fit and marked on the sides for alignment.

Chevrolet/G.M.C.

1931-32 Chevy car/1931-33 truck

For Automatic Transmissions XT-CA-AT $429

For Manual Transmissions XT-CA-MT $459

Automatic Tubular X-member for 1931-32 Chevy car/1931-33 truck

1933 Chevy Master/Standard car

For Automatic Transmissions XT-CB-AT $429

For Manual Transmissions XT-CB-MT $459

1934 Chevy Master

For Automatic Transmissions XT-CC-AT $429

For Manual Transmissions XT-CC-MT $459

XT-CC-MT shown, Right Hand Drive version

1934-35 Chevy Standard

For Automatic Transmissions XT-CD-AT $429

For Manual Transmissions XT-CD-MT $459

Automatic Tubular X-member for 1934-35 Chevy Standard

1935 Master/1936 Chevy Standard

For Automatic Transmissions XT-CE-AT $429

For Manual Transmissions XT-CE-MT $459

Automatic Tubular X-member for 1935 Chevy Master/ 1936 Chevy Standard

1936 Chevy Master

For Automatic Transmissions XT-CF-AT $429

For Manual Transmissions XT-CF-MT $459

Manual Tubular X-member for 1936 Chevy Master

1937-39 Chevy

*For Automatic Transmissions XT-CG-AT $429

*For Manual Transmissions XT-CG-MT $459

Automatic Tubular X-member for 1937-39 Chevy

1940 Chevy

*For Automatic Transmissions XT-CH-AT $459

*For Manual Transmissions XT-CH-MT $489

*Recomended (1) 7″ & (1) 14″ Top Hat Frame re-enforcement plates can be found here

Automatic Tubular X-member for 1940 Chevy

1941-48 Chevy

*For Automatic Transmissions XT-CI-AT $459

*For Manual Transmissions XT-CI-MT $489

*Recommender (1) 7″ & (1) 14″ Top Hat Frame re-enforcement plates can be found here

Automatic Tubular X-member for 1941-48 Chevy

1949-54 Chevy

*For Automatic Transmissions XT-CK-AT $429

*For Manual Transmissions XT-CK-MT $459

Automatic Tubular X-member for 1949-54 Chevy

1955-57 Chevy

For Automatic or Manual Transmissions XT-CJ $429

1934-36 Chevy truck

For Automatic Transmissions, Short Bed XT-CTB-AT-SB $429

For Manual Transmissions, Short Bed XT-CTB-MT-SB $459

For Automatic Transmissions, Long Bed XT-CTB-AT-LB $499

For Manual Transmissions, Long Bed XT-CTB-MT-LB $509

Automatic Tubular X-member for 1934-36 Chevy truck

1937-40 Chevy truck

For Automatic Transmissions, Short Bed XT-CTC-AT-SB $429

For Manual Transmissions, Short Bed XT-CTC-MT-SB $459

For Automatic Transmissions, Long Bed XT-CTC-AT-LB $499

For Manual Transmissions, Long Bed XT-CTC-MT-LB $509

1941-46 Chevy truck

For Automatic Transmissions, Short Bed XT-CTD-AT-SB $429

For Manual Transmissions, Short Bed XT-CTD-MT-SB $459

For Automatic Transmissions, Long Bed XT-CTD-AT-LB $499

For Manual Transmissions, Long Bed XT-CTD-MT-LB $509

Automatic Tubular X-member for 1941-46 Chevy truck

1947-55 (1st Ser.) Chevy truck

For Automatic Transmissions, Short Bed XT-CTE-AT-SB $459

For Manual Transmissions, Short Bed XT-CTE-MT-SB $499

For Automatic Transmissions, Long Bed XT-CTE-AT-LB $499

For Manual Transmissions, Long Bed XT-CTE-MT-LB $509

Automatic Tubular X-member for 1947-55 (1st Ser.) Chevy truck

1955 (2nd Ser.)-59 Chevy truck

For Automatic Transmissions, Short Bed XT-CTF-AT-SB $459

For Manual Transmissions, Short Bed XT-CTF-MT-SB $499

For Automatic Transmissions, Long Bed XT-CTF-AT-LB $499

For Manual Transmissions, Long Bed XT-CTF-MT-LB $509

Automatic Tubular X-member for 1955 (2nd Ser.)-59 Chevy truck

1963-66 Chevy/GMC truck, not for trailing arm suspension

For Short Bed XT-CTG-SB $589

For Long Bed XT-CTG-LB $619

Progressive Automotive 1963-66 Chevy/GMC truck X-member — 1963-66 Chevy/GMC truck X-member

1967-72 Chevy/GMC truck, not for trailing arm suspension

For Short Bed XT-CTH-SB $589

For Long Bed XT-CTH-LB $619

Ford

1932 Ford car/1932-33 (1st Ser.) truck

For Automatic Transmissions XT-FB-AT $429

For Manual Transmissions XT-FB-MT $459

1933-34 Ford car/1933 (2nd Ser.)-34 truck

For Automatic Transmissions XT-FC-AT $429

For Manual Transmissions XT-FC-MT $459

1935-40 Ford car/1935-41 truck

For Automatic Transmissions XT-FD-AT $419

For Manual Transmissions XT-FD-MT $449

Automatic Tubular X-member for 1935-40 Ford car/1935-41 truck

1941-48 Ford car

For Automatic Transmissions XT-FE-AT $419

For Manual Transmissions XT-FE-MT $449

Automatic Tubular X-member for 1941-48 Ford

1942-47 Ford truck

For Automatic Transmissions, Short Bed XT-FTE-AT-SB $459

For Manual Transmissions, Short Bed XT-FTE-MT-SB $499

For Automatic Transmissions, Long Bed XT-FTE-AT-LB $499

For Manual Transmissions, Long Bed XT-FTE-MT-LB $509

Manual Tubular X-member for 1942-47 Ford truck

1948-52 Ford truck

For Automatic Transmissions, Short Bed XT-FTF-AT-SB $459

For Manual Transmissions, Short Bed XT-FTF-MT-SB $499

For Automatic Transmissions, Long Bed XT-FTF-AT-LB $499

For Manual Transmissions, Long Bed XT-FTF-MT-LB $509

Automatic Tubular X-member for 1948-52 Ford truck

1953-56 Ford truck

For Automatic Transmissions, Short Bed XT-FTG-AT-SB $459

For Manual Transmissions, Short Bed XT-FTG-MT-SB $499

For Automatic Transmissions, Long Bed XT-FTG-AT-LB $499

For Manual Transmissions, Long Bed XT-FTG-MT-LB $509

Automatic Tubular X-member for 1953-56 Ford truck

1957-63 Ford truck

For Short Bed, specify transmission XT-FTH-SB $459

1964-72 Ford truck

For Short Bed, specify transmission XT-FTI-SB $759

Plymouth/Dodge

1933 Plymouth car/1933-35 (1st Ser.) Dodge truck

For Automatic Transmissions XT-PA-AT $429

For Manual Transmissions XT-PA-MT $459

Automatic Tubular X-member for 1933 Plymouth

1934 Plymouth car

For Automatic Transmissions XT-PB-AT $429

For Manual Transmissions XT-PB-MT $459

1935-36 Plymouth car

For Automatic Transmissions XT-PC-AT $429

For Manual Transmissions XT-PC-MT $459

Oldsmobile

1956 Oldsmobile, for Automatic or Manual transmission XT-O-56 $569

Optional Items

Vulcanized G.M transmission mount with attachment hardware TM-RM-C $12

Vulcanized Ford (non-Coyote) transmission mount with attachment hardware TM-RM-F $21

Vulcanized Ford (Coyote) transmission mount TM-RM-FC $59

Drive Shaft Loop kits, recommended for High horsepower vehicle XT-DLK $95