I agree that this is one area where I wouldn’t automatically go for the cheapest replacement just to get the job done. With a vehicle as large and heavy as a Navigator, the shocks have a pretty important job in keeping the ride controlled. A cheap part might fit correctly but still give you a noticeably different ride quality if its damping characteristics aren’t close to the original setup.

Before replacing the shocks, though, I’d make sure they are actually the source of the rough ride. A harsh or unsettled ride can also come from worn suspension bushings, incorrect tyre pressure, damaged tyres, springs, or other suspension components. If the vehicle has been modified with different wheels or tyres, that can make the difference even more noticeable.

For the shocks themselves, I’d look for obvious signs such as oil leaking down the shock body, excessive bouncing after bumps, increased nose dive under braking, or the vehicle continuing to move after hitting uneven pavement. Uneven tyre wear can also be a useful clue. If one corner behaves differently from the others, I’d pay particular attention to that side rather than automatically replacing everything.

If you take it to a Garage or Workshop, I’d ask them to inspect the complete suspension rather than simply saying “the shocks are bad.” A proper inspection should include the mounts, bushings, springs and other related components. That gives you a much better idea of what actually needs replacing.

I’ve also found that it’s worth comparing the exact part number and application rather than choosing based only on price. Two shocks can look almost identical but have very different valving and damping characteristics. That difference can be especially noticeable on a heavy SUV where ride comfort and body control both matter.

If the Navigator has any form of electronically controlled or air-assisted suspension, I’d be even more careful about choosing the correct components. In that situation, the system should be diagnosed as a whole before fitting replacement parts. Spending a little more on the correct component can be worthwhile if it prevents having to do the same job twice.