[Heideisadog]

So I have just recently started to get significant vibration through the floor on the drivers side. Actually I'm not to sure if it happens on both sides, should
Probay get someone to check.. But it happens around the 2500revs in 2-4th gear. Never had it happen till just recently (past few weeks)
What could be causing this? Uni joints starting to die? That's the only thing I thought could cause this.
Are the drive shafts/ tail shafts balanced or weighted? I have had them out not to long ago so if so they could
Be in wrong? Maybe a bearing somewhere

Sorry if I'm being quite noob with this, just chucking ideas out there!

Thanks,
Tom

[atari4x4]

sounds like a uni joint, could possibly be the ones in the jack shaft as they're usually the ones that are forgotten about plus feeling it thru the footwell rather than a shimmy/vibe in the rear.

did you mark the yoke on the unijoint & the flange on the diff & tcase when pulling them & did you line the splines on the slip joint up. i think the sierra's have a punch/match mark on them to line up.

[MrRocky]

Siezed unibor broken engne mount

[Heideisadog]

Thanks for that guys.
Are gresable unis the way to go?

Hmmmm not to sure I did that! Whoops! I marked the slip joint though!
I'll have a closer inspection soon!

Engine mounts are all good too.

[jdk81]

Sierras have punch marks to correctly align them in phase
no need to mark the diff and xfer flanges, and driveshaft yokes.

Sierra driveshafts can be put together unbalanced but still in phase (punch marks 180 degrees out).

Majority of aftermarket unis are greasable. Some have the nipple inside, others have it on a bearing cap.
Internal is more protected, but more of a pita to grease.

I prefer jap bearings.

If wheel bearings start to go you sometimes can feel a grinding/vibration through the floor

[Heideisadog]

Okay thanks for that! So helpful!!

Yeah all the ones I have seen so far have been greasable, guess that's what I'll get!

And wheel bearings were done not too long ago so I'll check them but they should be fine. Vibration isn't really a grinding feel abyway

Thankyou!