Sameer89

Hello All,

I've owned my IS F for a little over two weeks now, and I have noticed under several occasions under heavy breaking (close to 70-80% breaking capacity) that I have to fight the steering wheel to keep the car tracking straight. This is anywhere from speeds of 80-90 mph coming down to 40-50 mph. Could this be an issue related to the front control arm bushings? My F only has ~41,xxx miles and tires are brand new (OEM Spec) Continental ExtremeContact DWS. No other alignment issues known as the car doesn't track left or right either.

All insights are appreciated, and I am extremely happy to be apart of this community!

Regards,
Sameer

Vervish

iTrader: (4)

I had an issue when I switched to continental DWs (the summer only tire). With me, the car seemed to float (as if getting hit with cross wind). I had to make constant adjustments - this happened under acceleration and deceleration (not while cruising). After upgrading the LCA bushings and getting 3 alignments in a span of 1 month, it turned out to be a bad tire. One of my rear tires had something called radial pull - tire was replaced and the problem is 100% gone.

With that said - I would start by paying close attention to see if the issue is really only under braking. If it is, I would start with an alignment.

Compthis

iTrader: (1)

This is a direct result of the bushings. I track my car and know exactly what you are talking about. Braking the car from high speeds and having to wonder if the rear end would come around is an awful feeling. The moment I replaced my bushings, the issue was completely resolved.

PDP180180

iTrader: (3)

Bushings without a doubt.

Look into the RR-Racing USRS.

Had exactly the same unnerving experience until I had the USRS installed.

Not a problem anymore!

ZaxF

iTrader: (3)

These will solve all your squirmy braking issue for good! Figs zero deflection FLCA bearings.

Sylvan

iTrader: (6)

I had the same issue and got the RR-Racing Ultimate Steering Response System and it solved the issue.

MileHIFcar

https://www.clublexus.com/forums/is-...rr-racing.html

Hands down the best mod you can do for your F for the Braking and Steering feel bar none!

Sameer89

Thank you everyone for your help!! Much appreciated

Defratos

Yup as others have said LCA bushing will sort this out, I had the same issue and now zero deflection under heavy braking

lobuxracer

iTrader: (2)

Everyone has their own preference for which vendor's product, but all of them will solve the problem you have. It is without any doubt the front lower control arm bushing causing this. Replacing it with something harder will make the wandering feeling go away.

One2beH8ed

^^^^^^^ as said above. LCA bushings.

You have two options. RRracing or Figs.

I have RRracing and love them.

http://www.rr-racing.com/Lexus-Lower...isfxlca001.htm

BuLLdAwG

I'll add a 3rd option, which I have and love, RCF oem bushings. The improvement in braking and steering was immediately noticeable. I don't track my car so I figured these were more than sufficient. From time to time I do think about pressing in FIGS into the extra brackets just to compare.

itsmejon

I thought i put my breaks on wrong and one side was grabbing harder then the other. Glad im not that only one who had this issue, and even more glad that there is a pretty simple solution.

Sameer89

Oh wow, I didn't think about this! Has anyone else tried this option? I am assuming there is a revised part number for the bushing on the RCF.. Wonder if Lexus has superseded the ISF part for the RCF now?

BuLLdAwG

Someone else on the boards did try. I would credit them for me trying, but I don't remember who it was!

I ordered off mylparts.com under rcf. They are approx. $50 each after discount. I have no doubt the steering would be even stiffer with the FIGS or RR product. Maybe one day when this feels normal!

Edit: Jeff Lange was the person who I originally found that used RCF bushings.
Http://www.clublexus.com/forums/susp...duro-hp-9.html