Driveline Vibration

[philo_beddoe]

when driving down the road at 50, and then quickly drop in neutral, the vibe goes away quickly. would anyone say no way it could be torque converter? ya know, the only thing left is something in the rear diff. maybe over the course of my life i'll just start replacing part after part until i nail it.

[Irish_Alley]

since its not rpm related i wouldnt think the TC would be a issue. it has to be from the trans back to the tires. if you rotated the tires and the vib didnt change then i would think the rear. or even the drums???

[philo_beddoe]

I agree from the tranny back. I am also noticing when going down the hwy at say 50, then drop in neutral and back in drive, it somewhat goes away a little. I sure would love just to try another tranny...just to see what happens.

[zieg85]

Have you rotated the tires front to back?

[philo_beddoe]

Have you rotated the tires front to back?

Yes.

[MrFiveOh]

Double check your Trans Mount, I was told by Firestone it was good. I looked myself and and found out it was  crumbling.....

[philo_beddoe]

Just replaced last spring, brand new. Oh how i wish it was that !

[MrFiveOh]

Just replaced last spring, brand new. Oh how i wish it was that !

Just cause its new doesn't mean its good......

[philo_beddoe]

Yah, but not a complicated part, just a block of rubber, basically.

[Rattler12]

If it goes away after putting in neutral at 50 mph it's not your rear tires, wheels, rear end nor drive shaft as they are all still turning at close to the rate they were at 50. I'd say its in the trans or motor and probably  the motor since putting it in neutral at 50 mph reduces your rpms to idle and the vibration isn't present at idle whether standing still or coasting at 50 mph...jm2c's

[Irish_Alley]

I've had CV axles only vib when under throttle. Still there when you lift off but hardly noticeable. Have you took the rear cover off the differential? I would if you haven't and see if you see big metallic parts just sitting on the bottom.

[philo_beddoe]

Definetly something that turns/rotates. I will look into the rear diff., a while back i did change rear diff oil. I would like to check it again. I have to let  Vile Z. determine if any problem in rear diff though. I cannot move driveshaft in any way, no loose play at all. My tranny guy said there is really nothing in there that would cause it. Besides, why sometimes can i almost totally not feel it. I think i need to rule out rear diff and rear axle. That will tell me a lot.

[jg1977c20]

How tight are your exhaust system hangers?

i was just going to say ................ check the exhaust - i have flowmaster 40,s on and they give of some weird vibes going to lose those real soon . but i had to place pieces of rubber where the hangers attach to keep the reverberation down .

[philo_beddoe]

I really wonder if it could be coming from the tranny somehow. Is it possible??

It is NOT consistant, sometimes pulsating, sometimes steady, and sometimes is is really light and hard to detect.

[philo_beddoe]

https://vimeo.com/162083848

Nope, not tranny. Just went to a solid tranny shop and showed them the video here, he said that is way too much play. Thats my problem. Does anyone agree from the video.

But this is what Vile posted, so i dont know.

https://r.tapatalk.com/shareLink?url=http%3A%2F%2Fforum%2E73-87chevytrucks%2Ecom%2Fsmforum%2Findex%2Ephp%3Ftopic%3D32734%2Emsg280084%23msg280084&share_tid=32734&share_fid=15802&share_type=t&share_pid=280084

But i am starting to believe it is nothing between the grille and rear U-joint.