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, and at the bottom is either a steering box or a rack and pinion. From there, steering forces run out through inner and outer tyre 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. Replacement, in this case, becomes straightforward then.
Most replacement cases deal with traditional hydraulic rack and pinions, which have traditional failures, leaks, and so forth. There are many newer designs that are fully electric, and problems with them are rarer 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 cars it costs around £870 to replace a rack and pinion.
For some more specific estimates on some common vehicles, using £70 to £100 an hour as a labour rate, and adding in an amount for fluids and for re-aligning the vehicle:
- For a 2005 Honda Civic with a 1.7-litre engine, the labour time to replace the rack and pinion is 3.5 hours. A factory rack costs about £650, and a non-factory remanufactured rack costs about £380. This makes the job about £900 using OEM parts, or about £625 using aftermarket parts.
- For a 2004 Toyota Sienna with a 3.3-litre engine, the labour time to replace the rack and pinion is 3.6 hours. A factory rack costs about £610, or a new aftermarket rack costs about £330. This makes the job about £860 using OE parts, or about £580 using aftermarket parts.
- For a 2009 Chevrolet Malibu with a 3.5-litre engine, the labour time to replace a rack and pinion is 2.6 hours. A factory rack costs about £465, or a remanufactured non-OEM rack costs about £280. This makes the job around £645 using factory parts, or around £460 using aftermarket parts.
- For a 2014 Ford F150 with a 5-litre engine, the labour time to replace the rack and pinion is 1.6 hours. A factory rack costs about £945, or a remanufactured non-OEM rack costs about £755. This makes the job about £1,060 using OE parts, or about £865 using aftermarket parts.
Warranties for 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 heavy and very solidly made, in keeping with the large and heavy vehicles of the time. The main issue that plagued them was that seals would leak; the main seals were at the shaft ends and the input from the column. In many cases, they could be replaced with the rack in the vehicle, thus saving a great deal of labour.
But resealing racks and pinions is a much less common operation now. 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 pushed to operate closer to their mechanical limits.
Another reason is warranty, which doesn’t cover much of 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 was 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, as 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. In other 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 tie rod ends are removed from the old rack and transferred to the new rack. It’s quite 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 fine 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 are replaced, so any shop with a little foresight would do a good inspection of the front and rear suspensions to make sure that the alignment goes well and is worthwhile. Ball joints and bushings should be inspected, and if anything needs to be done on them, it should be done at the same time. In some regions 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 so. The other thing is to take it easy while driving; like many things in the car, the rack can also be 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 almost impossible to get enough access without having the vehicle up on a lift. In either case, it still needs to be aligned afterwards.