LEXUSA400

I'm surprised I didn't find anything when I searched, might not be using the correct words.

1997 LS400, 120,000 miles, new wheels, tires and alignment.

There feels like a small dead spot in the wheel where it doesn't steer. This makes going thru turns feel a bit clumsy not to mention I get some light shake at higher speeds sometimes. It felt exactly the same with the OE wheels and like new tires that came on the car as it does now with new wheels, tires and an alignment. The tech doing the alignment even found bad lower ball joints the first time I went in and had me replace them before he would align it. I think if there was something worn or loose he woulda found it and told me about it.

I'm thinking the rack is worn or out of adjustment and there is play somewhere. Maybe replacing the rack is the only option I have, no adjustment. Is this a common thing? Are the remanufactured racks from my local auto parts stores a good way to go?

SynicalVip

iTrader: (2)

Have you change inner and outer tie rod?

LEXUSA400

No. This could be the problem but I'm kinda surprised the guy who did my alignment didn't notice if they were bad.

Is this a common issue with the LS400?

What is the procedure for checking? Lift wheel off of ground and try to move?

LScowboyLS

strut bar bushing is more common, but I like to do inner and outer tie rod ends anyway, because it is so nice to have steering as tight as a new car!

also don't forget rack bushings

YoshiMan

See if you can get under the car and have someone turn the wheel several locks to the left and right. It sometimes will be very obvious what is wrong. The steering system on these is pretty direct and there is not alot of parts that can go bad, and its not common for them to do so as it is.

I pulled my rack on my 95 to make it easier to change the engine mounts, and discovered that the rack bushings were in terrible shape and starting to literally fall apart. Rubber parts like those don't like petroleum products, and they are in a prime spot for being exposed to anything that leaks, as well as all the road debris and such that gets kicked up at them over the years.

LEXUSA400

Thanks for the info. Are the rack bushings a dealer item?

I probably need new motor mounts too, I get some vibration when cold, I even wondered if the motor mounts might be part of the issue.

I did damage one of the outer tie rod boots so it will go sooner than later.

LEXUSA400

Where is the strut bar? I replaced all of the shocks and even the lower ball joints.

PureDrifter

iTrader: (10)

strut bar bushings won't have this type of effect ont he steering. this is definitely either a column or a rack-related issue.

LEXUSA400

This is what I was thinking. When I turn the wheel back and forth the steering column shafts look to move tightly without any play. I figured there was some looseness in the rack somehow.

Is there any adjustment to the rack?

If it will stop raining I'll get under there and pry on some things and might even be able to get a friend to turn the wheel for me.

If I do need to replace the rack, are the local parts stores remanufactured ones the way to go? AutoZone, Advance, O'Reilly's, PepBoys, NAPA ?

LScowboyLS

the rack itself is pretty darn reliable on LS400, I would start with inner & outer tie rod ends (aka rack ends) and also the rack bushings - go with dealership on those, except for on the expensive inner tie rods you can get away with raybestos pro from rockauto

and don't forget to get an alignment when you are done!

Largefarva

If it was just checked for alignment they should have done a full check on the steering components, in which case new tie rod ends are a waste of time and money. I'd say you have a bad steering shaft joint, you need to get under the car and look while someone turns the wheel inside, have them just move the wheel enough to see the play, you should also remove the inside lower cover and check the inside parts for wear using the same method. There should be two u-joints in the steering shaft, this is where your play will most likely be.

Kansas

Pure, you give the best advice on this forum but I have to disagree. My 2000 LS400 had a sort of sloppy unresponsive steering and vibrations at highway speeds before I had the strut rod assemblies, which included the bushings, at around 83,000 miles. Replacing the strut rod assemblies instantly transformed the car, made it drive like new, tightened the steering and completely eliminated the vibrations - it was like MAGIC.

My question to the OP is: Have your strut rod bushings or assemblies ever been replaced?

My 2000 LS400 is now at 174,500 miles and I really, really need to have the strut bar bushings or complete assemblies replaced again ... was putting it off but it looks like I am going to keep my LS longer than I had planned.

PureDrifter

iTrader: (10)

I didn't say it wouldn't have ANY effect, just that even rotted up strut rod bushings woudn't cause the type of "dead spot" play that rack/rod end issues will.

LEXUSA400

Speaking of alignment, what do you ask for, just what the manufacturer recommends? In the Miata world there are a few alignment options and they are so much better than what the OEM suggests. Some negative camber can do wonders for the feel of the car and not increase tire wear enough to worry about it. Anything other than zero toe can have the biggest effect on pre-mature tire wear and shouldn't be necessary on the LS regardless.

What is the process if these are the source of the looseness? Tighten? Replace? I think I only eyeballed one of the joints so maybe the other one is the culprit.

Someone please enlighten me as to what a Strut Rod Bushing is. The '97 has a coilover shock on all 4 corners, no struts. Ok, I just Googled it. The upper shock mount or top hat on my car is worn like I'd expect for the miles, 120,000, but all of the rubber is still in good shape and the hole the shock rod goes thru looks fine. These don't rotate when steering like on a car with struts, the upper and lower ball joints do the rotating when steering. I think the 2000 is the same, the early models had struts on one end, shocks on the other.

Kansas

Kneel on one knee forward of one of the front wheels; look inward for a "bar" that runs forward from the wheel suspension and attaches to the "frame" of your car. There is probably a much better way to describe it but that's the best I can do for now. These assemblies are known by a variety of names. I once posted a link in a post on this forum to an article ("Last of the LS400s") on www.autospeed.com that touches on why these "semi-longitudinal tension rod" bushings wear out so quickly.