I recently jacked up the rear drive wheel from my '86 Toyota truck to find out hwy rpms at hwy speeds.Before i could get to 65-70mph,the wheel was vibrating pretty strong.I don't remember feeling this on the hwy and i'm assuming it's out of balance,but the tires are only around 6,000 miles old or so.Should i just go get it rebalanced?
Fairly strong vibration when drive wheel is "float
- Thread starter daves66nova
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If the vibration is on flat surface then most likely the tire(s) is out of balance, if the vibration is on bumpy road then the shock/strut is bad.
The truck was not moving.I had the right rear wheel up in the air and the engine on and in 5th gear doing 65-70mph on the speedo.
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.
That is not something I would do to a differential.
That is not something I would do to a differential.
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Originally Posted By: wrcsixeight
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.
That is not something I would do to a differential.
+1
However, wouldn't the one wheel still spin at the speedo speed, with the open differential also spinning (instead of the opposite wheel?)
IMO, if it's not vibrating on the highway, then I'd forget about it. More over, unless you've got the car strapped down, doing what you're doing is dangerous if not damaging to the diff.
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.
That is not something I would do to a differential.
+1
However, wouldn't the one wheel still spin at the speedo speed, with the open differential also spinning (instead of the opposite wheel?)
IMO, if it's not vibrating on the highway, then I'd forget about it. More over, unless you've got the car strapped down, doing what you're doing is dangerous if not damaging to the diff.
Originally Posted By: wrcsixeight
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.That is not something I would do to a differential.
WOW!!! never knew that.I thought it would be speedo speed only.Anyways,i had it balanced and it needed an 8 weight.Is this grams?
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.That is not something I would do to a differential.
WOW!!! never knew that.I thought it would be speedo speed only.Anyways,i had it balanced and it needed an 8 weight.Is this grams?
Originally Posted By: wrcsixeight
That is not something I would do to a differential.
That is not something I would do to myself, that is, be injured or even killed by bits of an exploding tire which exploded because it was going 140MPH.
That is not something I would do to a differential.
That is not something I would do to myself, that is, be injured or even killed by bits of an exploding tire which exploded because it was going 140MPH.
Yeah imagine if spider gears overheated and ceased and caused the differential to grenade and transfer that energy to the other wheel resting on the ground.
That would be ugly. Wouldn't have to worry about that vibration anymore though
That would be ugly. Wouldn't have to worry about that vibration anymore though
Originally Posted By: wrcsixeight
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.
After thinking about this,why would it double the speed,yet only register 70mph on the speedo?
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.
After thinking about this,why would it double the speed,yet only register 70mph on the speedo?
Sorry, but I have to interject here....that has got to be the most unsafe thing a person could possibly do.
Its bad enough that jacks and jackstands collapse and fall on people. But to deliberatly jack up a wheel, Start the car, and put it into a drive gear and accelerate it........Glad you survived to tell us about it.
But for your own sake and the sake of others......don't ever do that again.
Its bad enough that jacks and jackstands collapse and fall on people. But to deliberatly jack up a wheel, Start the car, and put it into a drive gear and accelerate it........Glad you survived to tell us about it.
But for your own sake and the sake of others......don't ever do that again.
Even if the speed sensor for the speedo was on the differential it would still be spinning at 70 mph. The Spider gears in an open differential would be doubling the speed of the wheel off the ground. The only way it would read 140 mph is if it were doing 140, or the speedo sensor was on the one wheel off the ground.
As an experiment, lift both drive wheels off the ground, put it in gear, and let the idle speed in first gear only start the wheels spinning slowly. Take note of the speed, and then **CAREFULLY** and slowly stop one wheel. The other wheel will start spinning even faster as you stop the one wheel. The speedo will read the same.
Regardless, you got lucky you did not have all that kinetic energy release in a majorly bad way.
As an experiment, lift both drive wheels off the ground, put it in gear, and let the idle speed in first gear only start the wheels spinning slowly. Take note of the speed, and then **CAREFULLY** and slowly stop one wheel. The other wheel will start spinning even faster as you stop the one wheel. The speedo will read the same.
Regardless, you got lucky you did not have all that kinetic energy release in a majorly bad way.
And i had my niece's 2008 Accord right in front of my truck!and to think i even used a scissor-type jack on the axle to lift it! NEVER AGAIN!!!
When I was young I had a radio control car with a differential. If you grabbed one tire and held it still, the other tire sped up.
i finally drove it on the fwy.MAN,what a difference!!! smoother,quieter,i could drive in a higher speed without really noticing it!I'll try the other side now,but slower revs and in a safe area.
Originally Posted By: wrcsixeight
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.
That is not something I would do to a differential.
Or a tire not rated to spin that fast, although its usually the heat and not the centripetal forces that tear tires up. Still... seriously dangerous move. Even a pebble flinging out of the tread at that kind of speed could put a hurt on you.
If you only had 1 wheel off the ground, and your speedo indicated 70mph, then that one wheel was likely spinning at 140mph.
That is not something I would do to a differential.
Or a tire not rated to spin that fast, although its usually the heat and not the centripetal forces that tear tires up. Still... seriously dangerous move. Even a pebble flinging out of the tread at that kind of speed could put a hurt on you.
well, i had to do the other tire like this.this time i made dang sure i did it as safe as possible and only at 35mph on the speedo.Second wheel was good.
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