PLS help
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Toms240420
- Posts: 199
- Joined: Mon Sep 15, 2003 2:57 pm
- Car: My car
PLS help
i thank you for any info first off. well when i reach 55mph my car shakes badly all the way to about 65, then it smooths out. i already checked my tires for balance, pressure and i tighten up everthing i could find underneath the front suspention. i changed my TC rod bushings but this has suddenly become an issue. my tires are worn on the inside rim and i was told that my RACK and PINION was bad. How could you tell if the rack is bad? what all should i check over. i really need some direction becasue i want to either fix it myself or at least know something before i take it to get looked at. THANK YOU so much for your info.
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Toms240420
- Posts: 199
- Joined: Mon Sep 15, 2003 2:57 pm
- Car: My car
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
A dealer or Nissan specialists would be a good place to start.Normally 55-65-----70 mph vibration is tire wheel related.
Tire rolling circumference divided by speed 88ft/sec //yeilds a 13-14 Hertz vibration........measure the frequency and correlate with speed when vibration peaks for positive proof.
Now the rack/suspension is supposed to be designed to dampen the vibration.......via the pinion preload setting.
Tire rolling circumference divided by speed 88ft/sec //yeilds a 13-14 Hertz vibration........measure the frequency and correlate with speed when vibration peaks for positive proof.
Now the rack/suspension is supposed to be designed to dampen the vibration.......via the pinion preload setting.
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Toms240420
- Posts: 199
- Joined: Mon Sep 15, 2003 2:57 pm
- Car: My car
that is great to hear about the 55-70 wheel related. i just want to make sure before i go spend a couple of hundred bucks on tires right now if i dont need them. im just a poor man right now. the math shows that it doesnt take much to cause a violent shake right. but why does it seem to smooth out after 65 or so?
thank you so much for the info Q45.
thank you so much for the info Q45.
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Magnes
- Posts: 101
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- Car: '89 240SX, done up with a chrome-plated ground wire to the engine.
Actually 60mph = 7Hz for the average road car. I think you multiplied pi by radius instead of diameter to get circumference.Q45tech wrote:Tire rolling circumference divided by speed 88ft/sec //yeilds a 13-14 Hertz vibration........measure the frequency and correlate with speed when vibration peaks for positive proof.