Rough Ride At High Speeds

[pemarsh]

2004 lx470

lately, when going over 65 mph, i experience a rough ride...bit of vibration throughout the cabin, including floor and steering wheel.

Tires have been balanced, without relief

Car is being looked at again (lexus can not really reproduce it of course in their opinion). It is in dealer for 30x service (800$), and I was just told the front brakes need replacing and the rotors are warped a bit (600$ for basic front brake replacement and to grind the rotors a bit)

any thoughts?

[Jim_Chow]

Only other guess is the driveshaf(s) are out of balanced, possibly from hitting something (denting it can cause this) or a balancing weight has fallen off. The brakes should last a lot longer than 30K. I can't believe the calipers would have gone bad by then, unless you live somewhere where they salt the roads. The rotors can warp if the lug nuts aren't torqued properly (ie, to spec and with equal torque on each bolt). If they just use an impact wrench, the torques will be way off. Also, hard braking to a stop followed by staying on the brakes (like when you exit the freeway, brake hard to stop, then wait for the light to change) can warp the rotors. If you have to do this, then let the vehicle roll a tiny bit forward every few seconds so the heat evenly distributes. There was a recent thread about warping on ih8mud in the LC 100 section. In general, I don't find it worthwhile to turn (resurface) the rotors. It just makes them thinner, so they dissipate less heat, causing them to warp soon thereafter. An alternative to LC OEM rotors is DBA's.

Since the LC/LX is supposed to have its front wheel bearings repacked every 30K mi (you can push it much longer if you don't drive through water), one has to remove the rotor/caliper to access the inner bearing to do this, meaning if you do get this work done, installing the rotors is virtually no additional work (we're talking remove 5 or 6 bolts, bolt the new rotor to the hub). If they try to charge $$ for it, they're ripping you off. The bearing repack is a reasonably big job (like $350 [5 hrs labor] for a 4runner/LC80, so figure more for a LC100 or LX eventhough the amount of work and tools you use are identical, with the only difference being the parts [two paper gaskets and inner bearing seal per side]).