Nate.Evans

It doesn’t pull to the left or right, it just feels super vague and floaty under HARD braking. Think slowing down as quickly as possible from 100 down to 30.

If you’ve ever ridden a motorcycle, the biggest analogous explanation is like if the head angle is too steep, it all of a sudden feels twitchy when you brake really hard.

The car exhibits no other odd symptoms, it feels nice and tight when accelerating and in corners, but HARD braking just feels sketchy. Under normal braking there’s no issues.

I’m guessing it’s an alignment issue or maybe a blown shock? I got a look under the car and in the fender wells and the shocks don’t appear to be leaking or weeping.

GC996

Nate, it could be a lot of things: suspension may need to be refreshed, a caliper may need a rebuild, alignment and balance may be off.

Tell us about your car, what state you are in, tires you are running, suspension, etc.

sasilverbullet

+1 what he said...there's a lot of things that can be causing this, to include your tires.

Spyerx

Chassis setup / condition
tire wear condition / pressures
chassis rake (911 like *** up a bit)
diff. Open diff on a 911 causes tail wag under threshold braking. Lsd addresses.

Fishah

I would probably start with an alignment.

I believe OP has a 40Jahre so he's already got an LSD.

Prelude Guy

More than likely it's your suspension. How old are the control arms/shocks?

Nate.Evans

Sorry, brain farted and should have probably stated current setup.

40 Jahre @72k miles
stock suspension (still on original shocks/springs)
stock brakes (pads have been replaced)


I got brand new tires less than 200 miles ago (Z5s at the oem size). At first I thought it was the old tires as the ones that were on the car when purchased direly needed to be replaced and while it largely went away, probably like 90%, it’s still there. Waiting on getting an alignment as the local indy is booked until the 7th. I’ll be letting him know when I drop it off, but would like to have a general idea.

Car got a 60k mile service at the dealer and had the clutch and brake pads also replaced and the service receipt showed no concerns/notes on the brakes or otherwise. Then again, that’s the same dealer that replaced the clutch and didn’t feel it was necessary to change out the IMS 😂

GC996

Nate,

If I didn't mention it, congrats on your new 996! Awesome car and welcome to the 996 club.

Where are you located. I assume you are in a warm weather state since you have summer tires on?

Since we know your tires are new, it will most likely come down to one of the following.

1. Caliper sticking
2. Alignment & Balancing
3. Suspension

​​​​​​The car is 18 years old and as such, calipers will eventually need a rebuild, suspension components will wear out and need to be replaced, aligned and corner balanced.

Your shop can check all three, but keep in the back of your mind that you will pay twice for alignment if you do it first and then decide to replace your suspension. Same can be said for corner balancing which is very expensive and may or may not need to be done depending on if you plan on tracking your car.

As a side note, a car that is running more negative camber will have a tendency to track every nook and cranny on the road under braking. It does freek people out if they are unaware.

EVOMMM

The z5 need a good amount of heat to work properly also without a complete adjustable suspension replacement and performance pads your suspension doesn’t sound bad just old also a aggressive wheel alignment might help

dporto

Never take your car to a dealer if there’s a way to avoid it. Contact your local PCA chapter and find a good/great independent shop…

Nate.Evans

Thanks! I’m located in Greenville, SC. While it’s cold right now, generally speaking we have summer tire weather year round. I don’t have any plans on tracking the car, but will soon be getting new suspension soon regardless if it’s the issue or not…just trying to decide what I want to put on the car.

I didn’t think the suspension is worn, it still feels very tight, I’m just not as well versed in auto suspension to really know symptoms of anything…I come from a motorcycle background.

I’ve already found my local Indy, it was the previous owner that took it to the dealer.

hardtailer

OP's first sentence is 'it doesn't pull left or right'.
In my experience this excludes a sticking caliper as that would lead to pulling. Just sayin'... to all the contributors mentioning this as a possible cause.

168glhs1986

Nothing a set of $4000 coil overs, $300 corner balancing and a good alighnment $250 won't fix.

Also check your rear brakes to make sure they are working properly.

hardtailer

You're most probably experiencing small and varying toe-change due to worn rubber bushes in the suspension control arms when they are under the load of the high longitudinal braking forces
As such the rubber bushing in the front coffin arms to which the diagonal arms attach are suspect and at the rear primarily the toe control arms (the most rearward arm that runs horizontally at midlevel between lower and upper arms) as well as the rear coffin arms.

It will be worthwhile to check the condition of the (front) bump stops too.
After that I'd look at signs of leaking shock absorbers.

GC996

I wouldn't rule anything out on a car we know nothing about and have very little information on.

Just sayin...