Vibration at High Speed Causes? (1 Viewer)

[jskfj45]

so i'm getting the vibe too, just simply came about....This rumble vibration happens around highway speed most noticeable on deceleration even down to 45 or so. Put it in neutral, still the vibes. Going to re-balance the new tires, have new shocks.....ANY IDEAS?

 

[Cruiser4Lyfe]

so i'm getting the vibe too, just simply came about....This rumble vibration happens around highway speed most noticeable on deceleration even down to 45 or so. Put it in neutral, still the vibes. Going to re-balance the new tires, have new shocks.....ANY IDEAS?

I have been fighting a cyclical hum type vibration since I bought my 80 two years and 25,000 miles ago. It's most noticeable between 64 and 67 mph. I've done the following (though not just because I was chasing this vibration):

1. Replaced all u-joints and balanced rear drive shaft
2. Replaced front shaft with a brand new Toyota part
3. Changed rear output shaft seal in transfer case (it was leaking enough to leave puddles in the driveway).
4. Full front axle job
5. Had third member rebuilt by ZUK after finding metal flakes on the drain plug
6. Put new KO2's on it first week I bought it.

Seems like the intensity of the vibration increases with engine speed. Honestly, I think it could be my AC compressor that's giving me problems. None of the above repairs have changed the character of the vibration at all. Very frustrating, but at this point I've eliminated the issues that might put me on the side of the road, so I'm just going to drive it till it breaks.

 

[RAYJON]

Put a Gopro under the truck and drive it.. , amazing what you can see.. got the idea from jeese at high Angle driveline when he was trying to fix problems on some new motorhomes that were vibrating and mfg couldn't figure it out.. turned out to be pinion angle under extreme load..

did it on my dually chasing a vibration to find I had bent a wheel somehow.. works great for seeing the drive train move around under load and suspension cycling..

Anything not spinning smooth will be very apparent..

 

[RAYJON]

One I missed on my original post was motor mounts because the Toyota ones are overbuilt and last forever,. Bad mounts and the motor torquing over will cause some really weird stuff...

From my Chevy Blazer days where I tore them up all the time...doing stuff I probably shouldn't have done but I was young and stupid.. 4low burnouts were fun though...

 

[Nj2k]

I have been fighting a cyclical hum type vibration since I bought my 80 two years and 25,000 miles ago. It's most noticeable between 64 and 67 mph. I've done the following (though not just because I was chasing this vibration):

1. Replaced all u-joints and balanced rear drive shaft
2. Replaced front shaft with a brand new Toyota part
3. Changed rear output shaft seal in transfer case (it was leaking enough to leave puddles in the driveway).
4. Full front axle job
5. Had third member rebuilt by ZUK after finding metal flakes on the drain plug
6. Put new KO2's on it first week I bought it.

Seems like the intensity of the vibration increases with engine speed. Honestly, I think it could be my AC compressor that's giving me problems. None of the above repairs have changed the character of the vibration at all. Very frustrating, but at this point I've eliminated the issues that might put me on the side of the road, so I'm just going to drive it till it breaks.

Have you checked the harmonic balancer?

 

[Cruiser4Lyfe]

Have you checked the harmonic balancer?

Nope, wouldn’t know what to check as long as it’s bolted on there securely...