Hey guys. This is going to sound kind of stupid, especially for those of you who have 18s and 19s, but lately my car has been bouncing me around quite a bit. I previously had a 98 GS400 with 17s (Michelin Pilot A/S), and I now have a 99 GS400 with 17s (Toyo Proxes4), so I know how the car is supposed to ride. I've had the 99 for about 4 months now, and I just can't put my finger on it. It's really jittery over uneven surfaces, and I've seemed to develop a lot more rattles and looseness in the interior since when I first got it. I'm pretty tuned in to this kind of stuff, so I don't think I'm imagining it. It just seems as if the same bumps I went over 3-4 months ago (which caused no interior noise, rattle, looseness, etc.) now are causing a lot more jolts to the cabin. I bought the car with 64,000 miles and it now has 72,000, so it's not as if it was a baby when I bought it. I just don't get it. It's not that big of a deal, and I will be putting the 16s on in a month or so for the winter, but it just doesn't make sense. Anyway, any thoughts (and it's not the colder weather -- this was happening last month when it was still in the 80s here in the Chicago area). Thanks.

e-man

 

maybe a strut went bad? I know you felt it when it was warm but I'm sure cold weather will make it ride harsher and rattle more too . Air pressures have been the same whole time? Does the car ride worse now or have you just developed rattles.

I have a few rattles/creaks on my car,one from the gauge cluster. If I push the gauge cluster in it gets quiet for a while. that and my sunroof shade if I don't open it an eight inch. and one other mild one in my mid dash area in the mornings that I haven't located yet.

 

could be a lot of things, has it been in an accident??
Suspension??? Wheels??
Jack up the car and check around.
Or push the car down from the fender and feel the shocks.. maybe it is bad...
How many miles does it have??

 

72K out of shocks/struts is a bunch of miles. I would suspect those first, especially if they're still the originals.

 

Your Toyo tires may have firmer sidewalls than the Michelins. I'm guessing, of course, but I know what you mean by being in tune with every little noise. Try lowering the air pressure a little bit.

BTW, I run Toyo Proxes on 16" rims and the ride is substantially firmer when running 35psi versus 32psi.

JB

 

Thanks for all the replies guys. As far as I know, the car has never been in an accident. I agree with JB that the Toyos have a firmer sidewall than the Michelins, but the Toyos have been on this entire time, so it doesn't explain the difference in the ride from June-August to September-present. Chuck, I've been really vigilant about the tire pressure (because I have a few leakers), so it can't be that. I'm checking the tire pressure every week or so, and I keep it at 35 all around. As JB suggested, maybe I'll drop it to 32 and see if that makes a difference (the Toyos were filled to 40+ when I bought the car, and it wasn't rattling then). And Chuck, I've got the gauge cluster squeek too, as well as the occasional pop/rattle from the sunroof, but this rattling/looseness almost sounds like its coming from the doors (or maybe the windows in the doors rubbing against the weather stripping). The looseness is definitely not coming from the dash in front of me or the roof above me.

I guess my main confusion is that if the car wasn't rattling and felt solid from 65-70k miles, then why all of a sudden does it seem shaky, loose and rattly after 70k. It doesn't make sense that a car would be solid for the first 6.5 years and 70k miles of its life, and would then all of a sudden loosen up, does it?

 

Shocks or maybe shock mount