Weird vibration when coasting/decelerating in gear?

[Andrew_NZ]

1994 Surf KZN130, manual transmission, ifs, 2" lift (torsionbar/rear springs).

Hi, I went on a drive in the weekend, on the way out everything was ok, the gravel/dirt road on the way in had some pretty rough corrugations, at the destination I heard a bit of cv noise on full lock turning right (in 4wd), cvs were changed a year ago when I bought the truck, I realise the angles due to the lift increase wear but is a year of running/15,000kms enough to wear out a new set? On the way home I immediately noticed a whole vehicle vibration that only seems to occur when in gear and off throttle, coasting and engine braking, it seems most severe in city conditions slowing down for intersections in 3rd/2nd gear, but it is noticeable in all gears at all speeds to some extent but only when off throttle. Also I changed the idler arm about a month ago but couldn't wind the castle nut on enough to pin the hole (I'm monitoring it but still need to fix it properly ), the castle nut/idler arm is still tight.

Any advice on the best way to diagnose this? Cheers, you're help is greatly appreciated!

[Tankerman]

Vibration!

First thing to check is all the propshaft UJ's and the flange bolts!

[Diezel Weazel]

First thing to check is all the propshaft UJ's and the flange bolts!

"what he said"

16+ Years of Surfs n 9 years on Spotless it ain't but Faultless to a "T" is my KZN 130 Yota !!

[Andrew_NZ]

First thing to check is all the propshaft UJ's and the flange bolts!

Any advice on the best way to check this/what to look for? I watched a video where the guy jacked up one side and turned the propshaft/jiggled it to look for any abnormal play (what's normal /abnormal in this case ?). Any other tricks/obvious signs? Do I need to remove the propshaft to tell for sure if it seems ok? I'll have a go and get some photo's.

Cheers!

[pyemaster]

Shouldn't be any play, and zero rattling in your U-joints. Make sure they're greased up while you're down there, I make sure to do mine every time I drop the oil, every 10,000km.

If you do need to replace a uni joint, make sure you don't scour the bore of the yoke, that'll definitely give you play and ensure you are visiting your local prop shop to fit a new pair and rebalance the shaft.

Owen

[Andrew_NZ]

I'm guessing this is the culprit?https://youtu.be/NjNg7EEkdmE

Assuming that's not normal, is it worth changing the u-joint at the other end at the same time?

[Tankerman]

Vibration!

That'll be it! you may as well do both while it's off. When you take it off, mark the flanges so they go back as they came off.

[Andrew_NZ]

Shouldn't be any play, and zero rattling in your U-joints. Make sure they're greased up while you're down there, I make sure to do mine every time I drop the oil, every 10,000km.

If you do need to replace a uni joint, make sure you don't scour the bore of the yoke, that'll definitely give you play and ensure you are visiting your local prop shop to fit a new pair and rebalance the shaft.

Owen

That'll be it! you may as well do both while it's off. When you take it off, mark the flanges so they go back as they came off.

Cheers for the help and advice, got any other advice to help me avoid learning lessons the hard way :P? Any specialty tools that are worth having? I've read that having the right sized deep sockets to use as punches is handy?

[Tankerman]

Vibes!

And a vice!

[pyemaster]

Yeah just be careful if you're punching them out with a mallet and socket that you're knocking them out true - I definitely got a bit of a wonk on in removing one of mine and paid the price!

Owen

[tweak'e]

I'm guessing this is the culprit?https://youtu.be/NjNg7EEkdmE

Assuming that's not normal, is it worth changing the u-joint at the other end at the same time?

that diff in the vid looks like it needs a tighten up as well.

mark the two half's of the drive shaft in case you pull them apart. they must line up the same way.

[Andrew_NZ]

Cheers all, got it sorted yesterday, was a bit of a mission but the vibrations gone now. On to the next thing then I guess :P...