Dan Fletcher Super Stock Videos - Opinions

[Ken Miele]

I'm looking for some opinions on what you think the vibration in the video might be coming from. Dan has been fighting a vibration for the last few races, and can seem to find out what it might be.

The first video is from inside the car, go to 30 seconds to see and here the vibration.

The second video is the camera pointing at the u-joint. You will here a noise when he slows down but it is the brakes not the vibration. Its hard to hear the vibration in this video, but there is allot of movement in the pinion. Not sure that is the reason, but I thought it might be a place to look.

Any ideas, feel free to post.

[Larry Hill]

Might want to look at the tail shaft bushing. Just a thought.

[HR9121]

Had a similar problem when I had my HR car and as Larry suggested it was the tailshaft bushing.

[DrJRacing]

My limited experience with vibrations involved a bad shock (front).
Was most noticeable after the run during shutdown. A fellow racer (Rick Ryan) noticed a bouncing motion of my front wheel ...told me to check my front shock ...I did ...he was right. Thanks Rick and Jerry Ryan!
PS Congrats to Dan Fletcher on his latest Wins! Keep us informed on the final solution
Doug Jonak

[Mike Taylor 3601]

By the video I don't believe it is driveshaft, I think you would see it on video when it happened,may be able to see on slow motion? I would think you would see moving during vibration,don't believe it is in the pinion angle changes or would have other spots in the run,because looks like angle changes are about the same,didn't notice a change when it vibrated.
In a way almost sounds like gear noise
Does this only happen at this one point during shutdown?
Mike Taylor 3601

[Robert Simpson]

If you have not checked it already I would check the ring and pinion and bearings. It sounds like it is when you are slowing down so it would not be on the load side of the gear but on the coast side. Plus all the loads are in opp directions on the gears and bearings. Hope you find it. Let us know..

[tpoh815]

I think its the loose nut.............behind the wheel!

[cad]

Originally Posted by Larry Hill

Might want to look at the tail shaft bushing. Just a thought.

The bushing in my glide came out the rear while I was at Bandimere for ET Finals. The vibration was bad right on shutdown and deceleration. Nothing on acceleration. And it leaked, so it was noticeable when sitting.

[HR9121]

Originally Posted by cad

The bushing in my glide came out the rear while I was at Bandimere for ET Finals. The vibration was bad right on shutdown and deceleration. Nothing on acceleration. And it leaked, so it was noticeable when sitting.

When mine went bad also in a glide it only dripped a few drops in the trailer, only when I pulled the drive shaft out is when it was obvious what was wrong the bushing came out on the shaft. Be interesting to see what he finds. Mine started vibrating at about 1000'

[Lee Jordan (3223) A/S]

Originally Posted by Larry Hill

Might want to look at the tail shaft bushing. Just a thought.

I have had issues like this before and it wasnt the tailshaft bushing, it was the slip yoke on the output shaft. Over time it got loose and would only vibrate on deceleration, and would only be at a certain speed. I wouldnt rule out the gear either.