I was recently at NTB for a tire rotation. While waiting, the lady working at the counter offered to price up replacing my shocks/struts. The reasoning behind her recommendation to replace them was because I have 100,000 on my car, and according to NTB, shocks/struts need to be replaced every 50,000 miles because they go through several million or billion cycles over that distance.
Of course, I'm thinking "so what, that's what they are designed to do." I mean the engine has done somewhere around 200 billion revs (based on avg 50 mph and 2000 rpm) and that doesn't mean it needs to be replaced - because that's what it is designed to do. Needless to say, I don't plan on ever letting NTB touch anything more than my tires, and I'm seriously questioning that at this point.

The whole thing got me thinking though, how do you know when it is time to replace shocks/struts? I know an obvious sign is a severe cupping wear pattern on the tires due to the tire bouncing down the road, but are there any other indications?

Severe tire wear/cupping

Constant slow vibration at speed

Shocks/struts are wet with fluid (seals blown)

Constant slow bouncing after hitting bumps


If it's not doing any of these things just keep rolling.

100k is a good marker for preventative maintenance/replacement of shocks IMO, not 50k.

have you ever seen Uncle Buck?

Hehe...nice.

I rode mine to almost 200K on both my Silverado and Suburban. They still weren't bouncing or shot when I pulled them, but they were not 100% anymore.

I ran my previous trucks shocks to 105k. Didn't have any bouncing but the ride quality was considerably better after replacing them.

On a car with struts, 100000 miles seems fairly reasonable. If the car is riding like a 20 year old Buick, then it's probably time. If you do it, I would recommend getting the rubber bumpers and mounts replaced too.

What kind of car is it? Monroe makes a fully assembled strut (which has mixed reviews) that is very easy to replace for a DIY'er. If it is a Honda, they also make OE struts fully assembled that are just as easy as the Monroes, at about the same price, but OE quality,

Mr. Dubi,
Its a '06 Lexus GS300. Ride and handling are just fine.

I remember when I was in high school the parking lot check was to bounce on the front bumper, jump off and then see if the car stopped bouncing imediately or not. Sounds like that's not so bad of a test...

I guess I'd probably do it if I thought it would improve the ride and handling significantly, but I've really got no complaints in that area. I just thought it was comical when the NTB gal came to me with a $1000 estimate to replace all 4 and I wondered how many people actually fall for this crap - because that is part of their 50,000 mile recommended maintenance program. I started to ask her to add a headlight fluid flush and transmission rotation to her estimate. Not only that, but I was able to look up the part price on my iphone ($130 ea) while sitting in the waiting room.

Thanks for the advice!

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I wondered how many people actually fall for this crap

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my guess is, too many. but dealerships do the same thing.

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I guess I'd probably do it if I thought it would improve the ride and handling significantly, but I've really got no complaints in that area.

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I think that's the answer. The people in these places are in sales, there is no real money in tire balance, rotation and oil changes. The money is in suspension and brakes.

I never thought too much about them either, till I changed it on my Blazer one time.

I could take turns much faster and didn't feel like I was going to roll the car.


I have seen many a mechanic do the bumper test when the car is in the air (grabbing onto the rear axle or such). If you are getting more than a bounce or two, you need to change them.

Large amounts of shock to the springs can lead to damage to those components as well.

~egon