Intermediate Shaft

The intermediate shaft is the steel shaft that connects the steering column — inside the cabin — to the steering gear — under the hood or under the vehicle. It passes through the firewall and transmits the driver's steering input from the wheel down to the rack or gearbox. Most people never think about it until it starts making noise. Then it becomes the most annoying component on the vehicle.

The steering column and the steering gear are rarely in a straight line. The column comes down from the dash area at one angle. The rack sits low on the subframe at a different angle. The intermediate shaft bridges that angle difference using one or two universal joints — the same type of U-joint concept used in a driveshaft. These joints allow the shaft to transmit rotation even though the input and output are not aligned. Some vehicles use a rag joint — a flexible rubber coupling — instead of or in addition to a U-joint. The rag joint absorbs vibration and provides a small amount of isolation between the steering gear and the steering wheel.

The number one complaint related to the intermediate shaft is a clunk or pop felt through the steering wheel when turning from center, especially at low speed. This clunk comes from wear or dry lubrication in the U-joints or splined connection of the intermediate shaft. Over time, the grease inside the joint dries out or washes away and the bearing caps develop play. That play shows up as a distinct clunk at the point where the steering reverses direction — straight ahead to a turn, or turning left and reversing to the right. On many GM trucks and SUVs, this is one of the most common steering complaints. Some manufacturers offer updated intermediate shafts with better lubrication or revised joint designs as a service fix.

To confirm the intermediate shaft is the source, have someone sit in the vehicle and slowly turn the steering wheel left and right while you watch and feel the intermediate shaft from under the hood. Place your hand on the shaft near the U-joint. You will feel the clunk through the shaft at the exact moment the driver feels it through the steering wheel. If the noise and movement are at the U-joint, the shaft needs replacement. If the noise is at the rag joint connection to the rack, the rag joint may be worn or the rack mounting bolts may be loose.

The intermediate shaft is not just a noise concern. Worn U-joints introduce play into the steering system that the driver feels as a dead spot — a range of steering wheel movement that produces no response at the wheels. This dead spot makes highway driving feel imprecise and can mask small steering inputs during emergency maneuvers. A worn intermediate shaft also affects steering angle sensor accuracy because the sensor reads the column position, but if the shaft has play, the column position and the actual wheel position do not match perfectly. After intermediate shaft replacement, always check and recalibrate the steering angle sensor and verify alignment.