The rack and pinion is a newer alternative to the steering gearbox. Both take inputs from the steering column; at the top of the column is the steering wheel, at the bottom is either a steering box or a rack and pinion. From there steering forces run out through inner and outer tire rods to the steering knuckles at the wheels. The rack and pinion is a lighter, simpler and generally easier arrangement, especially on a front wheel drive vehicle.
There are a few different things that can wear out on a rack and pinion, though it’s also not uncommon for one to last the life of a vehicle. There are seals at the input shaft and both output shafts, which can cause external fluid leaks if they fail. There are internal seals that balance the steering assist between the two sides and can cause a pull or intermittent handling issues if they fail. There are bushings that hold the rack to the frame of the vehicle, which can wear and cause slack and play in the steering. And there are internal gears and bushings that can also wear out, causing binding or rough or sloppy steering. In a collision that damages the front suspension it’s not uncommon to have to replace a damaged rack and pinion as well.
How hard a rack is to replace depends mostly on how it sits in the vehicle. On a front wheel drive car the rack usually sits behind the engine, tucked in between the frame and sub-frame. It’s common to have to support the engine and lower the sub-frame to gain enough access to undo and remove the rack and pinion. On light trucks that use a rack and pinion, it will typically sit in front of the engine. Usually replacement is pretty straightforward then.
Most all of this deals with traditional hydraulic rack and pinions, which have traditional failures; leaks and so forth. There are many newer designed that are fully electric, and problems with them are more rare, so far. In many cases odd steering complaints can be solved with software updates. One of the advantages of electric power steering is that it allows a vehicle to incorporate lane-holding, automatic park and cruise control features, and eventually self-driving vehicles.
Costs of Rack and Pinion Replacement
On average for most vehicles it costs about $1000 to replace a rack and pinion.
For some more specific estimates on some common vehicles, using $100 an hour as a labor rate, and adding in an amount for fluids and for re-aligning the vehicle:
For a 2005 Honda Civic with a 1.7 liter engine, the labor time to replace the rack and pinion is 3.5 hours. A factory rack costs about $751, and a Maval remanufactured rack costs about $440. This makes the job about $1200 using OE parts, or about $890 using aftermarket parts.
For a 2004 Toyota Sienna with a 3.3 liter engine, the labor time to replace the rack and pinion is 3.6 hours. A factory rack costs about $702, or a new AAE rack costs about $381. This makes the job about $1162 using OE parts, or about $841 using aftermarket parts.
For a 2009 Chevrolet Malibu with a 3.5 liter engine the labor time to replace a rack and pinion is 2.6 hours. A factory rack costs about $534, or a remanufactured ACDelco rack costs about $323. This makes the job about $894 using factory parts, or about $683 using aftermarket parts.
For a 2014 Ford F150 with a 5 liter engine, the labor time to replace the rack and pinion is 1.6 hours. A factory rack costs about $1087, or a remanufactured Cardone rack costs about $870. This makes the job about $1347 using OE parts, or about $1130 using aftermarket parts.
Warranties of new and remanufactured parts are typically about the same – two or three years.
Resealing vs Replacing
Back in the early days (70’s and 80’s), rack and pinion assemblies tended to be pretty heavy and very solidly made, in keeping with the large and heavy vehicles of the time. The main thing that went wrong was that seals would leak; the main seals are at the shaft ends and the input from the column. In many cases they can be replaced with the rack in the vehicle, saving a great deal of labor.
But resealing rack and pinions is much less common of an operation since then. Part of the reason is that modern rack and pinions aren’t so heavily built, and often seals will leak because the shafts and bushings they seal are worn. Lighter parts tend to wear more when they are designed to operate closer to their mechanical limits.
Another reason is warranty, which doesn’t always cover much in a resealing job. For instance, if a rack is removed, resealed and reinstalled, and then comes back with an end seal leak, it might or might not be covered. If the seal was put in incorrectly or is defective it would be covered. But if it turns out that it leaks because of excess wear in the shaft bushings, that means not only is it not covered, but the resealed rack now needs to be replaced at the customer’s expense. Which puts everyone in a bad position, and it’s not always possible to predict problems like that.
But it is still worth a try sometimes to reseal a rack and pinion if it has developed leaks without any apparent reason, if it doesn’t show any signs of excess wear or if it doesn’t have too many miles on it. Sometimes a seal will just leak, and then a new seal will fix the problem. Or in many cases the cost difference between the two jobs is large enough that it’s worth trying the relatively inexpensive fix first, especially if the rack can be resealed without having to be removed from the vehicle.
What Else Might be Recommended
When installing a rack and pinion, the inner and outer ties rod ends are removed from the old rack and transferred to the new rack. It’s pretty common to have those replaced at the same time, especially if they are very old or show any indications of having issues. But it’s also ok to not replace them, on the general principle of not replacing non-maintenance items that are still working fine.
The alignment also needs to be done when the rack and pinion is replaced, so any shop with a little foresight would do a good inspection of the front and rear suspensions in order to make sure that the alignment goes well and is worthwhile. Ball joints and bushings should be inspected, and if anything there needs done it should be done at the same time. In some areas of the country rust is a big issue due to salted roads, and it’s a good idea to make sure adjustments can be made and things aren’t frozen up. It’s not uncommon to have rear adjusters, for instance, seized to the point that they need to be cut off and parts replaced. Things like that are better to find out before a job is started than on the last step, when it’s on the alignment rack.
The main thing is servicing the fluid. Clean fluid is a good lubricant, old dirty fluid is less good. The other thing is to take it easy driving; like many things on the car the rack is more or less stressed depending on how the vehicle is driven.
Usually yes, though it depends on how bad the leak is. If too much fluid is lost then power steering is lost, but if the leak is slow and monitored, usually it’s no problem.
On most trucks, yes, it’s not too hard. On most cars, no; it’s difficult to impossible to get enough access without having the vehicle up on a lift. In either case it still needs to be aligned afterwards.