How long should a UJ last

I seem to be changing on every 6months atm so they are lasting about 2 years. Is that about right or am I being short changed?
I use the gkn ones with grease nipples and they get greased at every service (6k) and after off road/green landing.
Has anyone got any recommendations on better quality unit?

quality and maintenance is everything got over 250k miles on a 13 year old truck. still on factory original

The UJ at transfer box front on my 90 lasts about 18 months whether I grease it or not.Others last several years.

Thor1950 said:

quality and maintenance is everything got over 250k miles on a 13 year old truck. still on factory original

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My Landy is 21 years old. I've had it for the last 12 years and never changed a UJ yet. No idea if any were changed before that, so it may still have the originals on.

You are making sure grease comes out of each cup?
Not changed my GKN for 15 years on rear.

It can also depend on the angle they're working at. For instance if you have a large lift on the suspension you could be throwing excessive strain on them. As @Hicap phill has already said, make sure that the new grease comes out of each cup and squishes the old stuff (and crap) out.

brian47 said:

@Hicap phill has already said, make sure that the new grease comes out of each cup and squishes the old stuff (and crap) out.

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I've religiously done this, every 6000 mile service. Mind you, my mileage is largely on the road with some green laning. 180K on the clock.

My Defender is 28 years old. I have had it 8 years and I've never had a problem with them.

brian47 said:

It can also depend on the angle they're working at. For instance if you have a large lift on the suspension you could be throwing excessive strain on them.

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No lift kit, Everything is standard other than heavy duty springs on the front for the winch. I do about 25k a year so they do a fair milage but as stated here I would expect a serviced UJ to last a lot longer than they are doing.

Hicap phill said:

You are making sure grease comes out of each cup?

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I was always taught to fill them until you hear the seal crack and then stop. If you over fill so that the seal bursts and grease comes out you are then allowing an access point debris to get in, but I will give it a go as currently it is not working.

Lifting suspension will put excess strain on your UJ's unless you modify the prop yolks.

I sometimes think replacement u/js are a waste of time even good ones and would say try a new prop and see how long that lasts.

tottot said:

The UJ at transfer box front on my 90 lasts about 18 months whether I grease it or not.Others last several years.

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Either the UJ's you are purchasing are not very good, or there is additional damage wear to other parts which are causing this. Or a mismatch of parts.

When they fail what is the normal mode of failure?

discomania said:

When they fail what is the normal mode of failure?

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The normal worn UJ problem of one/two cup disintegrated due to lack of grease although the others will look nearly new and will be full of it.

The amount of power going through them will also affect longevity - any engine mods? Although if you're getting 50k out of them with regular off roading I'd say that seems fair.

lynall said:

I sometimes think replacement u/js are a waste of time even good ones and would say try a new prop and see how long that lasts.

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I would agree, if you end up eating through UJ's (excluding cheap ones) then considering a brand new prop could end up solving the whole issue.

I bought 2 new prop-shafts about a decade ago and only had to change 1 x UJ on one of the shafts and I suspect it wore early due to a dirt ingress issue.

I also think that some people, and some of these people exist on this forum because I have seen you do it, are just not clean when working on cars and cause the damage yourselves. If you take the prop off, drag it through some stones and mud, then strip it down on the ground, while your brand new joint and cups sit on the ground picking up grit and dirt then assemble it all with your manky hand and don't clean anything properly then you are the root cause of early failure! When working on cars cleanliness really is paramount!

dag019 said:

The normal worn UJ problem of one/two cup disintegrated due to lack of grease although the others will look nearly new and will be full of it.

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When you fit them are you packing them with extra grease and pumping in some extra with a grease gun? Sounds simply like a lube issue.

A good quality grease is worth while, I have an original can of moly slip that I use a very small amount of for assembly of things, then use normal grease, it makes a marked difference, I have been using it on bearings and in engines (little dab under valve caps, rockers etc.) and all sorts my entire life and some of the stuff I built up with it years ago is still going strong and bearings look brand new etc. I am not suggesting you go to this extent but good grease and plenty of it should work a treat.

I'm sure I've read somewhere about greasing UJs after every off road trip - where crap under pressure can be forced past the seals, especially fording.

discomania said:

When you fit them are you packing them with extra grease and pumping in some extra with a grease gun? Sounds simply like a lube issue.

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Always, sometimes pack them with too much grease and have issues with "hydraulic lock" when trying to press them in as it tries to force the excess out of the grease nipple hole. then fit the nipple and grease again.
There is always one or two cups that are dry when it is removed despite regular greasing and the others look nearly new and are full of the stuff.
I grease everything on any reassembly unless there is a valid reason not to. Have a nice selection from standard copper grease to some old fashioned axle grease that is like tar and will never come off!

zeaphod said:

I'm sure I've read somewhere about greasing UJs after every off road trip - where crap under pressure can be forced past the seals, especially fording.

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Yes, and drain your swivels (if you can) axles and gearboxes and refill in case full of water etc... That's why I only ford up to the underside of my wheel-hub!

zeaphod said:

The amount of power going through them will also affect longevity - any engine mods? Although if you're getting 50k out of them with regular off roading I'd say that seems fair.

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I do that, uj and slider are greased at engine service interval and whenever I have been off road whether in water or not.