car problem: wheels vibrate while braking

[UR2KLOS]

Not bike related but there seems to be a lot of car experts here so I thought I'd ask.

Honda Pilot. Wheels are fine when driving but when I brake with moderate force the wheels feel like they're way out of balance. The rotors are slightly warped. Could this be causing the problem?
Thanks.

 

[TMS]

I'm no expert, but my wife has been know to warp rotors, both on a Subaru Wagon and a MiniVan and that out of balance vibration is what both my cars did.

 

[thomaswildchild]

Yes thats mostlikely the problem. my car had warped rotors for a while. it will shake the shit out of the steering wheel when braking.

Change the rotors and you will notice the diffrence!

 

[UR2KLOS]

Thanks. I was concerned it was a new unrelated problem.

 

[A-NON-A]

Bad front shocks/struts if its not your rotors. I drive 40k a year and its always one or the other.

 

[thomaswildchild]

Bad front shocks/struts if its not your rotors. I drive 40k a year and its always one or the other.

true! but since its only when braking im leaning more towards the rotors.... Ask to see the old ones if you have someone change them... Look for cracks and wear. Mine were horrible. the metal was cracked beyond belief.

Also You may need new pads too. warped rotors will mess up the pads as well.

you may look into cross drilled and/or slotted rotors, supposedly they disperse heat better, But a small part of me thinks thats a ploy to buy more expensive parts.

Finally if you dont slam on the breaks and drive more mellow, applying a more steady pressure to the pedal when braking, they shouldn't warp as fast or as bad.

 

[project_d]

I would be real surprised if the problem wasn't warpped rotors.

Warped rotors can happen when you're using them for long periods going down a hill, you let off, then you use them hard. Think of coming down the grapevine or into Santa Clarita Valley, and you'll know what I mean.

 

[DirtymikeTDB]

If your getting a shake while braking there is only a handful of issues you may have.

First of course, and the most likely uclprit.... warped rotors.... first place I would go if inspecting at my shop

Second would be maybe a worn tie rod, less likely, but worth checking.

third would be loose rack bushings, but you would probably also get a vibration when hitting bumps as well...

Shocks ans struts are not going to give you a vibration while braking, you would get a dive, and a roll during turning..........


check the brakes, chances are once you start getting a warped rotor, the brakes are going to be getting low as well.

 

[2wheel_lee]

There are a few things that could cause this, but it's most likely brake related. A qualified technician should test-drive the vehicle to diagnose the problem.

It's quite possible that the discs may be out of true or the parallism is out of spec. Either of these result in the discs needing to be turned.

Have the discs turned with an on-car brake lathe and install new pads. This is something that would be better done at the dealership, unless you happen to have an on-car brake lathe (of course if you did you wouldn't be posting this). At the same time, the dealer should also check to make sure the caliper pins aren't sticking.

Even if you do replace the discs they should always be resurfaced using an on-car lathe to ensure they turn true on the hub. Turning the discs off the car does not ensure they will turn true when installed.

And as part of regular maintenance, this may be a good time to replace the brake fluid. Honda recommends replacing the brake fluid every 3 years.

 

[UR2KLOS]

Great stuff. I would not have known to ask about the on-car lathe.

 

[2wheel_lee]

Great stuff. I would not have known to ask about the on-car lathe.

If you take it to a Honda dealer, you won't need to ask - that's all they use. It's a hit and miss at independent repair facilities.

 

[quikflip27]

If the vibration is still new, try doing a few hard decelerations (don't come to a stop) from 50ish to 10. The warping of a rotor isn't usually from an out of true rotor, but rather uneven brake deposits on the rotor from the transfer layer between the pad and rotor. The hard decelerations induce heat into the transfer layer may be able to break down the old and create a new even layer.
If this doesnt work, pepboys can machine down the rotors for $10 each.

 

[Formu1fan]

I'm no expert, but my wife has been know to warp rotors, both on a Subaru Wagon and a MiniVan and that out of balance vibration is what both my cars did.

+1
I warped the rotors on my mom's Subaru Outback wagon. It make a lot of shaking while under braking. The sent it to a machine shop to trim a little off and make it even, and it was good as new!

 

[UEDan]

Yes it is the rotors, end thread. The Pilot is a huge vehicle, if you're warping the rotors. You might need to invest to bigger rotors.... or stop braking so damn hard!

Also You may need new pads too. warped rotors will mess up the pads as well.

you may look into cross drilled and/or slotted rotors, supposedly they disperse heat better, But a small part of me thinks thats a ploy to buy more expensive parts.

True

True, some can be worst than blank ones. ie cheese grate the pads.

If this doesnt work, pepboys can machine down the rotors for $10 each.

If the rotors aren't too bad, sure go for it. But you will eventually need to change the rotors.
Machining rotors = BAD. You loose metal, metal needed to disperse heat.

 

[fatguy1]

go get some american , japanese or canadian made rotors and some ceramic pads and put them on its very simple. these rotors are floating....no need for a overpriced dealer. turning rotors is a thing of the past anymore since rotors are so inexpensive now.people get nailed for brake jobs all day long i would hate to see that happen to you good luck if you need any help pm me i will lend you a hand and the tools if needed:beer:

 

[Heyitsdave]

You made your tostadas into tacos:lol:. Throw them away and get some new ones.

 

[simoncpj]

One other thing. If you just got new tires or had them rotated, then never return to the shop that installed them. If you over-torque the lugs, it will warp rotors on many cars.

 

[Jeepdude]

It has been my experience that most aftermarket pads will warp the rotors much faster than factory pads. People will get the lifetime pads thinking that they will never have to buy pads again, but the pad material is much harder and destroys the rotors. You won't have to buy new pads again, but you end up replacing the rotors. If you get them turned, you need to make sure they have enough material or you will be under spec and will have to replace them.

I always use the factory brake pads.You can never go wrong there.

 

[2wheel_lee]

these rotors are floating....no need for a overpriced dealer. turning rotors is a thing of the past anymore since rotors are so inexpensive now.

Incorrect. The discs on the Pilot do not float. The calipers float.

It is a perfectly acceptable practice to turn the discs until they meet the minimum thickness specification. As mentioned above, even installing brand new discs will require that the runout is checked, and if the runout is out of spec they may need to be turned on the vehicle to ensure they are true with the hubs. Again, this is if you want to do the job right.

My suggestions are intended to maintain and service the vehicle to the same high standards as it was manufactured.

 

[Shu]

Incorrect. The discs on the Pilot do not float. The calipers float.

It is a perfectly acceptable practice to turn the discs until they meet the minimum thickness specification. As mentioned above, even installing brand new discs will require that they are turned on the vehicle to ensure they are true with the hubs. Again, this is if you want to do the job right.

My suggestions are intended to maintain and service the vehicle to the same high standards as it was manufactured.

The biggest problem is if they are warped bad....they will over turn them "claiming" that is what it took to make them true again and then they will be beyond the minimum allowed and they will need to be replaced....this happens WAY TOO OFTEN in WAY TOO MANY shops and dealerships....if they have been turned ONCE there will be NO WAY they will be able to be turned again...