Diagnose This, Please

[4RunnerNewbie]

So, I've had various issues with rotors over the years. Nothing has really helped, I've consistently had issues. Most recently I put on EBC brakes and rotors.

About 1.5k miles ago, I developed a slight vibration while braking, so I got the rotors turned using a Pro Cut on the car lathe.

It didn't really do much, I still have an SLIGHT, INTERMITTENT vibration when braking between 60-65 MPH.

I also have developed a SLIGHT vibration while driving. This can be seen in the steering wheel. This also occurs in the 60-65 MPH.

So, I don't think I've had vibrations due to rotors - I think I've been noticing the vibration while braking, but haven't really paid attention to the vibration while driving.

The issue is pretty minimal - I can only notice it if I take my hand off the wheel. I once thought it may be related to low profile tires (not my choice, on the vehicle when I purchased it), and the tires were flattening out when the car sits, but I still notice the vibration after I've driven for a while.

So, has any else had a similar issue? What else would cause this vibration? Unbalanced wheels? Alignment issues? Crappy Tires? Something causing rotor wear?

Maybe I just need to forget about the vibration and enjoy the fact that I have a pretty good car.

 

[BlackWorksInc]

What kind of rims and wheels do you have installed? Is this vibration noticable when driving as well as braking? Does the vibration change over different road surfaces. Is there a noise associated with the vibration as well?

It could be anything from wheel balance issues, up to the front differential having issues (I had a noise/vibration issue in my 4Runner that only happened between 65~70mph and ended up being a burnt bearing in the diff.)

 

[goohead]

IMHO prob ur rotorsa

I would buy some decent rotors pads w lifetime warranty and just swap if needed in future instead of turning

Advance auto parts Wagner pads and Wagner rotors are pretty good and they will swap for you as long as you keep the receipt. They got same warranty w the calipers too. I just did all 4 and front calipers.

 

[4RunnerNewbie]

The vibration is noticeable while driving AND while braking.

The car has an XSP package, so it came with 20'' rims and they have low profile Kumho tires. No noise with the vibration. I've tried to notice a pattern as to which road surfaces it appears on, but I can't seem to find a pattern. It almost always happens when I've first gotten in the car, but it's also happened when I've been driving around for a while.

I have a really hard time believing that I have rotor issues again. I have a good quality rotor and pad on it currently.

 

[CookieRoe]

There was a thread not too long ago about a mysterious vibration. Turns out it had something to do with wheel balance and how important it is to have balances on BOTH sides of the rim as opposed to only one. Try it out, it won't cost too much, it may solve your problem

 

[4RunnerNewbie]

I'll try to locate the thread. Thanks for the insight.

I'm really leaning towards a balance issue - I just don't know how it could be rotors, given that they are relatively new and it's an intermittent problem at a particular speed. Maybe I'm wrong, but that doesn't seem like a brake issue?

 

[MikeInNH]

The vibration could be the rotor.

With these rotors...there are 4 pistons (2 each side of rotor). And if one is sticky it causes uneven pressure on the rotor..and this can cause a vibration when you brake.

 

[4RunnerNewbie]

Wouldn't a stuck piston cause the wheel to not spin freely?

 

[MarkieG]

Wouldn't a stuck piston cause the wheel to not spin freely?

You are correct if the piston was stuck in the position when the brakes were applied, thus clamping on the brake rotor. However, a piston can be stuck in the non-brake applied position as well. If that's the case, then at least one pad within the caliper is not getting applied directly parallel to the rotor - which could cause the vibration.

Weird it is happening when brakes not applied, sounds like may be something other than the brakes.

 

[galactic_04]

It's wheel balancing. Have a tire shop balance them and you'll be fine

 

[4RunnerSeth]

Were the brakes properly bedded after the last turn and new pads? generally vibrations in braking are due to uneven pad wear and or glazing. This is usually caused by improper or no bed in done after replacement.

Some good reading on this:

About Bedding brakes:
Stock Brake System Bed-in

About the Myth of Warped Rotors:
-Warped- Brake Disc and Other Myths

 

[nevada]

It's wheel balancing. Have a tire shop balance them and you'll be fine

yup. its a tire problem.

that is not to say that you dont also have a rotor issue. but the vibration at speed, while NOT braking is a tire issue.

 

[aha2988]

I certainly think Its def. a tire or alignment issue. dealing with the same issue right now just installed fresh rotors, pads and a new driver side caliper still have a slight steering vibration durring driving no longer durring braking. getting the tires balanced today and aligned ill post up tomorrrow and let you know if this solves my problem.

just in my situation next step is new CV axles as with my lift there running at pretty negative angles if thats not the culprit then the only other thing can be the bushing that the rack and pinion mount to are warn out and the whole rack and pinion assembly has play causing the vibration.. I'm chasing the same problem bro so we'll get it worked out..