Forgive my lack of knowledge with this....

So, when I first got my Lexus...It had gotten a flat on the road, and the guy had put a stock wheel he had for the car, though it was only a 16, and the car is dropped on 19s. The tire size of the 19s are 245/35 r19, and the spare was 215/60 r16....and when I was driving it home from about 20 mph to about 50-55 the car would like shake/seem wobbly. but at 60 it drove smooth. But I did have about and hour and a half drive home.

I replaced the tire that needed replacing, and have been driving the car around for a week now, and the shaking/wobbliness had stopped, and now it is starting to mildly shake from 35-50 mph, while you speed up, but more when you press on your brakes...

I have no clue what to check, should i get all the tires remounted and balanced? Or could it possibly be rotors/calipers/ brakes over all? I get super paranoid and even think as far as to go get my engine an overall inspection to make sure the mounts are still good...Please do give me some suggestions as to what this could be.

Could possibly be an alignment issue? & was the tire that was fixed rebalanced after you replaced the tire?
 
I know that the GS is prone to a wobbly steering wheel....

Yes it was rebalanced, but I didnt know that about the gs....though....I feel like it is the entire car? Idk, i am super paranoid, and hear EVERYTHING and can feel everything in the car.

if your getting shaking/vibration from the steering wheel while braking you should have your rotors checked out for warping.

to be honest your problem sounds like an alignment or wheel balancing issue though.

[QUOTE=Mrs.Rodriguez;414254]Yes it was rebalanced, but I didnt know that about the gs....though....I feel like it is the entire car? Idk, i am super paranoid, and hear EVERYTHING and can feel everything in the car.[/QUOTE]
 
Hmm, that's odd that it's the whole car? Maybe it does have something to do with your alignment.. 
 
 
Here's a thread on Club Lexus about what people hate about the GS: 
[URL]http://www.clublexus.com/forums/gs-second-generation/153381-things-you-hate-about-gs.html[/URL]
 
Shaking steering wheel is one of the top complaints. :shrug:

[QUOTE=Brandicus;414255]if your getting shaking/vibration from the steering wheel while braking you should have your rotors checked out for warping.
 
to be honest your problem sounds like an alignment or wheel balancing issue though.[/QUOTE]
 
 
Agreed. A lot of people warp their rotors. If you take your car to a car wash after driving it.... hot rotors from braking + cold water = warped rotors.

Thats what I was thinking maybe the rotors? But at the same time it is also doing it as I speed up too and that threw me off.....But I think that I will go in and get an alignment done as well.

Since its an aftermarket rim, maybe your missing those little spacers that fill in the gap between your hub and the rim. I believe they are called hub centric spacers, any rim shop should be able to get you some.

Heres a picture of what they look like..

[IMG]http://www.1010tires.com/images/accessories/hubrings_large.jpg[/IMG]

I would suggest checking if you have/need those since its way cheaper than an alignment.

[QUOTE=Anonymous User;414349]Since its an aftermarket rim, maybe your missing those little spacers that fill in the gap between your hub and the rim. I believe they are called [I][B]hub centric rings or spigot rings[/B][/I], any rim shop should be able to get you some.
[/QUOTE]
Made a little correction. Might easily give you similar vibrations without 'em, and it's easy to check if you have 'em in place.

If you're paranoid a bit little sounds here and there. Modified cars probably isn't for you lol

@ 4DGS: You sir would be incorrect. 

@ Juzzo: That is very helpful, I will look into this! Thank you!

I think you just need to get an alignment. Anytime you make changes to your tires wheels suspension you are supposed to have one. Now none of us get them because we generally will live with this stuff or run crazy setups/camber that an alignment wouldn't do us any good. However since you gave your suspension stress by running different sized wheels/tires for a little bit it might of thrown your toe off or something else that an alignment would fix.