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Discussion Starter #1
I finally got tired of the excessive amount of vibration at highway speeds in my Deville. I had new tires installed with Road Force Balancing, rotors turned and brake pads replaced. I read through my Helm and found out that excessive rust on the hubs and the back of the rotor can cause vibration. I spent 2 hours cleaning the rotors and hubs with PB penetrating fluid and a large drill with a rust removal brush attachment. I test drove the car, and the vibration has been eliminated. Who knew a little bit of rust could cause that much problem.
 

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2008 DTS Perf-Plat, fr 11 STS, 04 DeV, 76 Eldo Con, 74 Fltwd
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Are you saying that replacing tires and resurfacing rotors did NOT fix the problem, but rust-removal did? All four wheels or just the front?
 
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Ever do a repair, take it for a test drive and think "yes" its fixed. Next time you get in and drive it a bit more and its doing it again?.
 

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White Diamond '03 DHS (with DTS floor shift)
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I would suspect that the new tires and RFB are what did the trick.
 

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2001 DTS / 1973 fleetwood
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wow, you mean after all the discussion on this vibration at 70 mph, has been solved with RFB ? interesting.

more interesting is about the rust....i wonder how much weight in corroded metal you have sanded away !

actually the OP should have done the RFB, and then a week later, did the rust removal, just to isolate the two, to more accurately determine what got rid of the vibration..

still no vibration btw??
 

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2008 DTS Perf-Plat, fr 11 STS, 04 DeV, 76 Eldo Con, 74 Fltwd
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I had a RFB done a month ago, which improved, but didn't eliminate the vibration. My LR tire was slowly losing air, so when I had it state inspected on Thursday, I had them check the tire. They replaced the tire pressure sensor for $15 and pumped up the tire. Now the vibration is gone.
 

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Discussion Starter #7
Sorry, some clarification is in order...

When I bought the car, I replaced the tires with Goodyear Eagle GS-H's. Initially, I had the "free" balance (not Road Force) done on the tires. This solved the severe vibration, as one of the old tires had a bulge in it. However, there was still considerable vibration.

After the tires, I replaced all four brake pads and had all four rotors turned. I didn't bother to remove the rust from the rotors or hubs, as the Haynes manual made no mention of rust removal. The brake pulsation continued.

Later, I had the tires Road Force Balanced, and I had the mechanic check for any runout in the wheels. Wheels were perfect. After the Road Force Balance, I noticed improvement, but still not perfect. I also had problems with the brake pedal pulsating and the chassis shuddering when I was braking at around 80mph.

Finally, I received my Helm in the mail (What a blessing!). After reading the troubleshooting guide for brake pulsation, I decided to remove the rust from all four rotors and hubs. That solved the rest of the vibration issues and the brake pulsation.

Ive driven about 300 highway miles since, and the vibration has not come back.

I have never experienced such issues with vibration with any of our vehicles. I've noticed that the A-arms look like they are cast aluminum, and the a-arm bushings appear to be polyurethane. I would think that this would make the car extra sensitive to any imperfections.
 

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White Diamond '03 DHS (with DTS floor shift)
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These cars seem to be very sensitive to vibration. I too still have a slight vibration after a RFB. Worse after I rotated the tires so I rerotated them back to where they where (I think). Still not prefect. I'm curious as to just how much rust was on them? I may have to consider trying this.
 

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Discussion Starter #9
There wasn't a whole lot of rust on the rotors or the hubs. Mainly just surface rust. I believe the critical area for rust removal is on the chamfered inner most radius of the back side of the rotor. The same goes for where that surface mates to on the hub. Those are the areas I noticed the most rust.
 

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White Diamond '03 DHS (with DTS floor shift)
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Hmm. OK, I've got a job for tomorrow, but I'm not holding much hope. I noticed the vibration after a tire rotation and lessened it after rotating them again so I suspect tires, but it is worth a shot.
 

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95 Fleetwood Brougham / 01 DTS / 11 CTS Lux / 11 DTS Platinum
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Very interesting. When I do my brakes I'll be sure to performs the rust removal.

Thanks for the tip
 

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Discussion Starter #12
Yep... I wouldn't call cleaning a catch all cure. The only thing that tipped me off to brake rotor/hub rust was very noticeable brake pulsation during heavy braking at speeds > 70-80mph. The brake pulsation was not noticeable at any lower speed.

One thing that the mechanic who did my RFB noted was that I should always maintain the tire pressure at which the RFB was performed. (Mine was done at 35psi). If the tire falls below that pressure, the vibration will come back.
 

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White Diamond '03 DHS (with DTS floor shift)
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The only thing that tipped me off to brake rotor/hub rust was very noticeable brake pulsation
Ah, in that case I'll save the effort.

One thing that the mechanic who did my RFB noted was that I should always maintain the tire pressure at which the RFB was performed. (Mine was done at 35psi). If the tire falls below that pressure, the vibration will come back.
Hmm, interesting. I'll have to look into that.
 

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I though it may be the tire air pressure sensor weight, mine needs a lot of counter weight to balance so even though they are balanced they still have 2 heavy sides. Or am I the only one that has all the tire weights just opposite the valvestem/airsensor ? I put on a set of STS 16" rims / michelens without the tire sensors and I still have vibrations but they are less and the speeds changed. These tires are used and I don't know their history but they are done this fall so for now I just drive in the no vibration zones. I think I will do the roadforce balance on my new snow tires on the STS 16" this fall and see what happens. Once I hear anyone else back up the rust removal remidy I may try that when I am switching tires anyway, So Ranger did you try it yet?.
 

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White Diamond '03 DHS (with DTS floor shift)
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No. After post #12 I decided that it was not an issue as I have no brake pulsation.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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:thumbsup: Go back in one of my Seville Shimmy posts of 8-10 months ago, where I mention a good cleaning of the wheel/rotor mating surface. 9,500 miles later, even after changing to the Cooper CS4 235/55/VR17's, I have zero vibration. And it's QUIET !!
 
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