violent vibrations

[japerry]

So this weekend as we were driving up to Snoqualmie Pass, I was trying to take the 4runner over 45mph. Once I hit over 40-45mph, the whole truck starts to shake violently. This occurs in 2wd or 4wd. It also occurs if its in front-wheel drive (rear driveline detached)

Another interesting thing is that it shakes even more violently after taking off my foot off the gas pedal.

The steering wheel does not shake itself, and it surprisingly does not pull to one side or the other, so its in fairly good alignment?

Any ideas?

 

[cisco]

This might sound dumb but heh.... Have you gotten all the ice out of your wheels?

 

[Maverick26]

Sounds like tires are out of balence if it hapens around that speed. Could be a drive line too. Lug nuts tight?

 

[TreeClimber]

Couple of ideas

Rear driveline U joint about to explode.
Bent rear driveline.
Bent rear wheel.
Bent rear axle.
Lug nuts loose, wheel wobbling on axle.
Massive tire weight issue, such as full of ice, snow, mud, etc

 

[nevada]

size and make/model of the tires?

 

[Pat]

Another interesting thing is that it shakes even more violently after taking off my foot off the gas pedal.

This sounds like possibly a pinion angle issue?

 

[japerry]

size and make/model of the tires?

Irok 37x14.5x15

This sounds like possibly a pinion angle issue?

Good question, its pointed up a bit...

Rear driveline U joint about to explode.
Bent rear driveline.
Bent rear wheel.
Bent rear axle.
Lug nuts loose, wheel wobbling on axle.
Massive tire weight issue, such as full of ice, snow, mud, etc

When coming down from the pass, my tires were full of ICE/snow... that might have explained why it was much worse on the way back than the way up.

Would any of these issues explain why it vibrates really bad when I take the pedal off the gas? its an Auto Trans (700r4).

 

[410ZukiGirl]

Holy Bad Pinions, Batman!!!!!!! bring that bitch down! or put a cv back there. I have a cvrear shaft that is ver long and could be used if shortened.:awesomework:

 

[nevada]

those radials? i havent kept up with the tires, and what sizes come radial or bias?

and the pinion angle might be high, but its not the cause of the problem...it did it without the rear DL.


my vote is the tires..balance..

 

[TreeClimber]

Bias tires will flat spot something fierce when sitting, and it's worse when cold outside. However that vibration should be noticable at slow speeds, not only at highway speeds.

The other things to consider are axle wrap (especially in a springover). If you wanna test it, have someone stomp on the brake pedal with the left foot, and then go from reverse to forward under load (by gassin' it) and you watch the rear pinion. If the pinion moves violently up and down as the tranny goes into forward and reverse, you're springs are too soft and you need an anti-wrap device. (Also maybe you have loose spring U bolts)

Regarding the vibration. YES you can get a vibration from pinion angle. On my CJ, before I went CV shaft, I'd get a noise/vibration which sounded like the rear tranny bearing going out. However I was wrong. Once the CV shaft went in, and I corrected the rear pinion angle, the noises all went away.

 

[410ZukiGirl]

tire shake/wobble dont change with throttle applied/cut.

What the front shaft look like/made from?

 

[Darby1]

I hear that pinion bearings go bad real quick when their turned up that high

 

[410ZukiGirl]

I hear that pinion bearings go bad real quick when their turned up that high

X2, if the rear looks like that, lets see the front. please I hope its not a picture of a square shaft.

 

[TTF Fabrication]

i have what sounds like the same problem. i checked u bolts, driveline bolts, lug nuts, etc. motor mounts? but that takes away our common denominator. my fix to the problem is to buy a car. ill post up if i figure it out.

 

[zukkev]

That Pinion is pointed waaaayyy too high by the looks in the pic....remember, when you load the springs, that pinion is going to go up even more, causing a worse angle yet!!! A cv might make it better, but likely won't fix it all---cut the perches & turn the pinion down---will help alot/if not eliminate the vibes...

 

[japerry]

That Pinion is pointed waaaayyy too high by the looks in the pic....remember, when you load the springs, that pinion is going to go up even more, causing a worse angle yet!!! A cv might make it better, but likely won't fix it all---cut the perches & turn the pinion down---will help alot/if not eliminate the vibes...

That might be worth taking a look. Although it is a cv drive shaft. Also found out that one of the tires was low.. only 10psi, the others at 23psi. =D it still vibrates, but I gotta go faster now (45-47mph)

 

[gas is on the right]

hey did you ever fix your lockers.... If i remember right they were stuck locket? is your front driveline spinning when your moving in 2wd:corn:

 

[gas is on the right]

also air your tires to around 30 and see what happens

 

[gas is on the right]

tire shake/wobble dont change with throttle applied/cut.

What the front shaft look like/made from?

you sure know alot for being a woman:eeek: :eeek:

 

[japerry]

i have what sounds like the same problem. i checked u bolts, driveline bolts, lug nuts, etc. motor mounts? but that takes away our common denominator. my fix to the problem is to buy a car. ill post up if i figure it out.

Motor mounts probably need some checking.. I managed to break the tcase crossmember, so that should be done.
ubolts, driveline bolts (now), and lugs are all tight.

hey did you ever fix your lockers.... If i remember right they were stuck locket? is your front driveline spinning when your moving in 2wd:corn:

Yup, both elockers work perfectly now. =P and no, when its in 2wd and unlocked hubs, nothing inside should be spinning (I can turn the front driveline)