Strange noise - auto hubs?

[Barrbeast]

Hi folks

Just a quick one, driving home last night and as I applied the brakes on the approach to a roundabout I heard a thunk followed by a whirring noise (a wee bit like a ratchet) which slowed down as the truck slowed down then stopped as I came to a standstill followed by another thunk once the truck had stopped moving then nothing for the rest of the journey. Noise seemed to come from the offside front I think. Not heard it again and I drove into work fine this morning.

Was it my wheel hub? (Y61s have combination auto/manual hubs, default setting is auto) :nenau

 

[solarman216]

not sure about your hubs but I would be having a look and make sure they are lubed up correctly,on the T2 if the inner hub gets dry it starts to turn from friction from the outer and causes problems, Rick

 

[makeitfit]

Yep as Rick said, get your hubs out boyo. Strip down, clean and gently regrease. Check for breakage inside though as the auto manual gizzmo can snap and leave little shards of steel in the works

 

[Barrbeast]

Cheers Rick, Pete

Had a look at the Patrol 4x4 forum as well and it looks like a strip down and re-grease is definitely required.

Not heard the noise again though and I've driven almost 80 miles since I heard it, so hopefully things will last until the weekend when I can do something about it!

 

[Barrbeast]

Have had more of a rake through the Patrol 4x4 forum and I have two more queries...

1) Had a look at the downloads for the Mav hubs but just want to check - copper grease is what I should be using isn't it?

2) A lot of the guys on the Aus forum recommend avoiding a full dismantle, just firmly hit the hub on the bench with the open end down and the inner parts will come out in one piece then clean up and lightly grease/oil - thoughts?

Also I was going to take the wheel off before removing the auto/manual hub but just thinking about how it all fits together do I really need to remove the wheel? :nenau

Cheers!

 

[davenclaire]

no need to remove the wheel

 

[solarman216]

not sure about Patrols but T2 hubs have a multi turn circlip holding it all together, Rick

 

[Barrbeast]

Well, I took both hubs off and had a look at them before I did anything - both looked lightly greased and all in one piece, as did the splined stub from the axle. put them back on the stub and they spun freely by hand :nenau Stuck a couple of the bolts in, switched the hubs to lock, removed the bolts and I could turn the hub and prop no bother... so I'm stumped!

Didn't see any point in dismantling them, am wondering if the noise was just some random event as it hasn't happened again

The joys of vehicle ownership :lol

 

[makeitfit]

Yeh less worry more drivey :thumbs

 

[Barrbeast]

Yeh less worry more drivey :thumbs

:thumbs Exactly bud... and now I've fitted my oil pressure gauge I don't even have to worry about the intermittent warning light (I really must pull that dash bulb)

 

[Barrbeast]

Thought I would post this more for interest than anything else!

Basically, the noise came back last night and I noticed it was definitely dependent on how fast I was moving (and once I braked it was gone, not to return).

Very much a whirring noise and since the auto hubs are working fine I figured it must be something to do with the front prop. Quick check of the Patrol 4x4 forum and I'm pretty much 99.9% sure it was the front prop causing the noise - apparently if it's cold and the truck is sat for an extended period (like at the carpark at work) then, if the oil in the transfer box is thick enough, the the swirling oil from the rear prop turning can make the front prop turn also. The turning prop engages the auto hubs and that makes the noise. I'm guessing by the time I brake the oil is warm enough that it doesn't do it anymore.

Nissan's fix was to put thinner oil in the transfer box (sounds like a bodge to me - the transfer box can work hard at times, why put oil in there that's thinner than it should be! ). Some of the Aussie guys have manual hubs anyway so it isn't an issue for them (tempting) but there are others who just live with it. Can't imagine it causes any real damage, just the odd noise.

Have ordered some new oil for the transfer box anyway as it's overdue an oil change - that may have somethng to do with it as well.

 

[Fez_uk]

Thinner oil in our climate isn't always a bad thing.

 

[Thomas-the-Terrano2]

interesting about oil thickness

think had that once on cold snowy day in car park, might have used 4wd on way to
work.

leaving in 2 wd got thumping, did feel prop related, maybe dog clutch had frozen in 4?

went as soon as it started.