Some parts wear out slowly enough that you’d be heard pressed to tell when it’s time to change them. Shock absorbers are like that. Sure, if they break, they’ll rattle around under your car and you’ll know something’s up. But if they just slowly wear out, the change in ride quality is hard to notice…especially when you drive the car every day.
A generally accepted rule of thumb is that shocks should be replaced at around 25,000 mile intervals. Some shocks, particularly your ultra-premium brands like Koni, will last longer than that, but that doesn’t mean they don’t need minding. The parts under your car not only wear out from just doing what they are supposed to do, but the inhospitable environment under your car take their toll too. Rain, sleet, snow, gravel and other road hazards throw a beating into undercar parts like your shocks so it’s a good idea to take a look and see if they are damaged or leaking.
If they are undamaged physically, the old bumper push test can tell you if your shocks have had enough. If, after pushing down on the bumper it takes more than one or two cycles for the shocks to settle the body movements down, it’s time for new shocks.
The front shocks on my Marlin were damaged beyond repair as I highlighted in a previous installment. The rear shocks looked like they had been under the car since the ‘80s and the body took three or more cycles to settle down after the bumper test. They weren’t leaking and appeared undamaged externally, but after getting them out of the car their condition could be better diagnosed. The passenger’s side shock was tired, but still damping suspension oscillations. The driver’s side could be compressed and extended by hand with little effort proving that it had completely had it.
A new set of Monroe gas shocks were ordered from Rock Auto.com and somehow the installation went off without a hitch. Seriously, replacing shocks is not a particularly difficult task and doing them yourself can save you some cash. The hardest part of the installation for me was climbing into the trunk of the Marlin. The car’s fastback roofline forced a rather small trunk lid to be used on a car with an otherwise spacious trunk. Loading my banged up, 50-year old body through that small portal was my biggest challenge. A younger, more flexible person may not have struggled so much.
Check out the photos and see how I did it…maybe you can do it too?