1927-1959 Tie Rod & Drag Link End Repair
By Stephen Kassis
Steering problems on early Chevrolet cars & trucks with straight axles are usually easy to diagnose. Bad king pins, worn or out of adjustment steering box, or worn or out of adjustment tie rod or drag link ends are the three areas of concern. Once the king pins and steering box are repaired or confirmed good, the next step is to check and tighten up the tie rod & drag link ends.
Starting in 1927 Chevrolet had a new drag link design. The ends of the drag link had threaded plugs that held cups, pistons & springs in the ends. These pieces mated up with ball studs that were in the end of the pitman arm (on the steering box) and the steering control arm (at the brake backing plate). This design was also used on 1932-1938 passenger cars & 1932-1959 trucks in the tie rod ends.
The design is versatile in that pressure can be increased (or decreased) by adjusting the plug at the end of the tie rod or drag link. Adjustment is simple. Remove the cotter pin that keeps the end plug from turning. Using a very large screwdriver and an adjustable wrench, turn the plug down tighter against the spring, pistons & cups. Reinstall the cotter pin and you are done! If you are unable to get the end to tighten up, there may be a broken or collapsed spring. This is the most common failure with this type of end. If so, it will be necessary to install a repair kit with new springs, cups, pistons and plug ends.
The beauty of this design is that the internal pieces of the drag link or tie rod end can be replaced quickly. Unless the housing itself is worn or damaged, the internal pieces can make the end like new in minutes. The kit (FS-148) does two tie rod ends for 1932-1959 or two drag link ends for 1927-1954. This kit replaces worn cups, pistons and heavy springs – all of the internal part of the ends.
We were frustrated with the quality of repair kits that were on the market, so we made our own. Some of the other kits had improper opening clearances in the cups which made installation difficult or impossible. Our kit was copied from original 1930’s Chevrolet pieces. It is engineered to match the factory pieces exactly, both in dimensions and materials used.
The specific DRAG LINK applications are: 1927-1952 All Commercial & 1927-1954 All Passenger (Note: 1937-1938 (Series GB & HB with straight axle) re quires two kits to repair the drag link ends. The TIE ROD END applications are: 1932-1938 All Car & Trucks (Except 1933-1936 Standard â CC,DC,EC,FC and 1937-1938 Master models with straight axle); 1939-1959 All Commercial (except Double-Duty D-D). Make note of the order of the internal parts as you disassemble the tie rod or drag link end. Be aware that reassembly of these ends can vary by year and application. Refer the shop manual for your vehicle for the specific order. Also note that these kits are made to replace the internal parts for either two tie rod ends or two drag link ends. There will be one piece in the kit that is not used in each application.
Inspect original ball studs for wear. If worn, the ball studs are replaceable. Original ball studs were pressed and/or welded in place (some applications had bolt in ball studs). New ball studs are available for drag link or tie rod applications. They are available for weld-in or bolt-in applications. SA-157 & SA-603 are the press-in type and SA-157T & RW-603T are the threaded versions. Tie rod ball studs for straight axle applications: 1927-1959 Passenger car & Trucks. The shank diameter is .530″ (or 13.46mm) and is not tapered. The head diameter on the new ball studs is 1″ (or 25.4mm). The shank length is .950″ (or 24.13mm). Compare with your original to be certain that they are the same size.
Drag link ball studs for 1947-1952 trucks are two different sizes of shanks: One stud is .631″ OD (or 16.02mm) and one stud is .7525″ OD (or 19.11mm). The ball head OD on both is 1″ (or 25.4mm).
To remove the original ball stud, check for welds. Grind off any welds until they are removed completely. If there are no welds, the ball stud was pressed into place. Use a 20-Ton press and carefully press out the old ball stud and press in the new stud into place. Weld the bottom edge of the ball stud to secure it. CAUTION: it is important to get a proper welding job done on the ball stud. Failure of this part can cause catastrophic results. It is recommended that the welding is done by a certified welder.
As an option, we have available the threaded type of stud. Either method will work but the reproduction studs have straight sides with no taper. IMPORTANT: If your original stud has a taper, these studs will not work as a replacement. Carefully compare the dimensions of the original stud to the new stud before installation. They should be an exact match to the original.
Installing the new inner parts of the tie rod or drag link ends is a simple process. Refer to the notes from disassembly or to the shop manual designed for your model of vehicle. The shop manual should indicate the proper procedure for installation. Once the internal pieces of each end are installed, align the cup openings to allow them to slip over the ball stud. Grease the face of each cup and press the end into place over the stud. Tighten the plug end and install the cotter pin. The final step is to grease the end using the grease fitting. Lubricate these ends often as they have no boots to keep out dirt as was done in the later designs. This is also a very high wear area and regular lubrication is vital.
Note: 1953-1959 trucks used fixed end drag links and must be replaced as a unit.