Diagnosing a Tie Rod Boot Leak: An Overview

A leaking steering rack seal is the most common cause of a tie rod boot leak

But a damaged tie rod boot can cause the rack to leak. The inner tire rod boot has one job; to keep dust and dirt away from the inner tie rod end (the ball and socket that allows the arm to move left/right and up/down). The boot is clamped on one end to the steering rack housing and on the other end to the inner tie rod shaft. As the rack moves in and out of the steering gear housing, the accordion style boot opens and compresses. However, if the steering rack seal fails, power steering fluid can cause the tie rod boot to leak oil.

These images show a typical rack and pinion steering gear with inner tie rods and boots

But a damaged tie rod boot can cause the leak as well.

Sloppy repair work when replacing an axle shaft, or a lazy alignment technician can easily damage the inner tie rod boot. Here are some examples.

In the upper left you see what happens when a lazy alignment tech adjust the toe angle without first disconnecting the boot clamp. As they turn the tie rod, it twists the boot. From that point on, the boot can’t easily compressor extend and eventually fails. In the lower left you see what can happen when a careless tech uses a torch to remove a rusted bolt. The heat from the torch melted the tie rod boot. On the right you see damage from fluid contamination, wear and age cracks. Once the boot is damaged, road dirt and grit can get into the rack seal area and wear out the rack and seal

How to replace inner tie rod boots

1) Loosen the jam nut on each outer tie rod end.
2) Disconnect each outer tie rod end from the steering knuckle.
3) Unscrew each tie rod end, counting the number of turns for each side.
4) Remove the two clamps securing the inner tie rod boot to the steering rack and inner tie rod and remove the old boots. Note the location of the “breather bypass” tubes connected to each boot.
5) Slide the old boot off the rack and replace with the new boots. Re-insert the breather bypass tubes.
6) Secure the new boots to the rack and inner tie rod using the clamps provided in the boot kits.
7) Screw the old the outer tie rod ends back onto the inner tie rods by the exact number of turns you noted during removal.
8) Install each outer tie rod end into the steering knuckle. Add the castle nut and torque to the specified torque. Secure with cotter key.
9) Tighten the outer tie rod end jam nut.

Inner tie rod boot replacement cost

New inner tie rod boots cost about $45 (shop price). The labor to replace both inner tie rod boots is about 1.5 hours shop time. So the entire job should cost $200 – $250

©, 2022 Rick Muscoplat