How long do aftermarket struts tend to last (Sensatrac)? (harsh ride on 97 Accord)

I own a 97 Accord. I replaced my stock struts at 90K with Monroe
Sensatracs. The car has 140K now. I recently replaced my worn Michelin
X-one tires with Goodyear Assurance Comfortred which are known for
their smooth ride. However after replacing the tires, I noticed that my
bumps cause shudders in the chassis and many bumps and expansion strips
cause harsh impacts. I played around with tire pressure, which didn't
seem to improve the ride, only worsening it. After noticing degradation
to the rubber shock mounts under the hood, I had them replaced. The
ride improved for a short period of time but became harsh again
(perhaps the fresh rubber was more compliant before wearing in). Before
I replace the struts with a new set, I would like to get some feedback
on this. I know that Monroe recommends replacement of their sensatracs
at 50K, however such a harsh ride seems abnormal for only 50K.
I had them installed at Sears and Monroe brags about a "lifetime"
warrantee. However I don't understand how they can recommend a 50K
change interval while claiming a lifetime warrantee. Also I was under
the impression that worn struts get floaty rather than harsh.
I would appreciate some advice.

 

shocks can get harsh after time - they de-gas and subsequent cavitation
of the damper piston in its oil can be quite rough at higher piston
speeds. for future reference, honda shocks usually last a good deal
longer than 90k. many shops recommend changing too soon on hondas
because 1. they make money & 2. are used to dealing with detroit garbage
that barely makes it to 40k. regarding "lifetime", what does that mean
exactly? it's certainly not /your/ lifetime. it doesn't usually mean a
thing for projected longevity either, just that something's warranted
against factory defects. something can be worn out, but still free of
factory defects.

regarding your problem though, if the ride was fine before the tire
change & rough after, doesn't that indicate that it's a tire issue?
just because a tire has a certain name, doesn't mean it actually lives
up to it. i've messed about with a number of different brands of tires
and have found there to be significant differences in ride. michelin
hydro edges were so rough, i took them off again. i mean persistent
headache rough. air pressure didn't make much difference either.
michelin rain forces on the other hand were great but are now
unavailable. currently, i have continentals and they're just fine.

 

Seems like your springs are also do for a replacement.

My guess is, the aftermarket shocks are just as good as Honda's product.
But, If you want exceptional shocks, get the performance variation. I've got
200,000KM on my Tokico and their still going good. I can still blast over
railway tracks without any drama or power around bumpy roads without loosing
traction. My tires are quite noisy, since they're getting old, so I don't
notice the extra noise from imperfections in the road (It's all bad, but
that kind of noise factor is simply do to the tires...if the tires were
newer I'm sure flaws in the road would be more noticeable instead of getting
drowned out).

The Eibach Pro-Kit springs (which are progressive springs and are as
aggressive as those springs found in high performance European sedans) and
with the Tokico shocks, will return a slightly stiffer ride, but the extra
stability is reassuring. Also, this setup will better handle pot holes or
drastic railway tracks. Even with the tight springs and shocks, you'd still
have the loosy-goosy tires to soften the ride, or the option to drop in some
low profile variation to complete the package.

Pars
98 Civic Hatch

 

"The car has 140K now. I recently replaced my worn Michelin X-one tires
with Goodyear Assurance Comfortred which are known for
their smooth ride. However after replacing the tires, I noticed that my
bumps cause shudders in the chassis and many bumps and expansion strips
cause harsh impacts."

I would have a tech look over the entire suspension...you may have some
worn bushings or other components.

Also, did you notice a difference in the ride when you replaced the
struts at 90k? My guess is that it stiffened up some.