High speed vibration

[Blackdog]

Hi All,

Ok my few weeks was a bit more.

From the top:

1- New uni joints - still vibrating
2- Balanced tail shaft - still vibrating (though if you ever get the chance to watch then do it do so. Pretty cool process. In a long lathe bed and spinning at 3000 rpm. Heat applied through oxy torch and quenched to straighten and balancing hubs on each end like a tyre balancer.) shaft was a bit out but didn’t fix the vibration.
3 - Pinion bearing - changed diff ratio and therefore bearing and no change
4 - gearbox bearing - did not change
5 - rear housing extension bush - I sources another extension that ended about the same amount of wear as I already had. I had a lot of dramas trying to source sintered bush material to turn a replacement up. So I thought to in the mean time try something. I pressed out the bush (gentle, both the bush and the housing are soft materials) and wrapped some 0.02 shim stock around the bush and re pressed it back in. I Checked for smooth fit and no binding with the yoke and with the shim stock/soft bush seems to be enough to reduce the diameter enough to take the play out of the housing bush. So I’ll keep monitoring this while I source some bush material.

#5 on the gearbox output shaft housing bush seems to be the vibration cause for me in this case.
Test driving the past month and all good.
Heat gun checks show the output shaft isn’t running hot also

I’ll wrap this post up here.

Blackdog

[Errol62]

Great result. Thanks for posting. I have read that bush and yolk are a matched set from new and should not be separated, but after all these years….


FB ute fixer upper, EK van on rotisserie

[Blacky]

JP , when did this vibration start ? A few years ago a mate licenced the hotrod he had built and it had a vibration in it that took quite a bit of sleuthing to find, ended up being his front rims were out of round.

Did the vibration starting coincide with any of your wheel/tyre/brake upgrades ??