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Leaky CVs

Posted: Sat 18 Feb, 2012 10:54 am
by Brad.Jones
Hi Guys,

My sierra leaks grease out from the CVs, after a days driving just around town usually the inside wall of the front tiers are splattered with grease.
Very similar to what is described in this document: http://homepages.maxnet.co.nz/martincat ... 0Joint.pdf
Should I be concerned? Is it something that needs fixing asap or can I just squirt some more grease in somewhere until i do get around to fixing it?

Thanks

Re: Leaky CVs

Posted: Sat 18 Feb, 2012 1:29 pm
by Greg
that seal is easy to fix brad. it's litterally a wheel off, then lean in a remove 8 bolts, new seal goes in, put 8 bolts back, put wheel back on. easy.

if you are concerned that you have lost too much grease - then you need to do a bit more work (remove the spindle) to put more grease back in there.

i think the seals come in a 'sierra knuckle rebuild' seal pack.

Re: Leaky CVs

Posted: Sat 18 Feb, 2012 7:44 pm
by gwagensteve
Brad, it's likely that the inner axle seal (the last image on the link you posted) has failed, and diff oil is weeping into the CV housing, washing out the grease.

That's why it's falling out of the knuckle seals. If it wasn't being diluted by the gear oil, it would stay where it was.

However, the method for getting in there in link you posted is the most complex way possible.

If your wheel bearings are in good condition, the procedure is as follows:

Remove the wheel
Remove the brake calliper bolts& calliper. There is no need to remove the brake hose so bleeding isn't required.
Remove the brake rotor
Remove the 6 6mm bolts on the free wheeling hub.
Remove the cir clip.
Now you can get to the spindle bolts. Remove them (you can't use a ratchet or ratchet spanner, you will need a 14mm ring spanner
Now the whole hub will come off without disturbing the bearings.
Pull the axle out
clean out the CV housing
pull the seal
Replace the seal
Put it all back together.

It won't take more than an hour per side.

I don't think its necessary to change the knuckle seals - if I'm right, they will be serviceable, it's the dilution of the grease that's the problem

Steve.

Re: Leaky CVs

Posted: Sat 18 Feb, 2012 7:50 pm
by Brad.Jones
You guys are such a wealth of knowledge. I appreciate it a lot.
So you recon I can get away with just replacing the one seal...
I have only managed to find knuckle rebuild kits which are about 100 bucks per side which seams crazy if all I need is the one little seal.

Would repo / super cheap have what I need?

Re: Leaky CVs

Posted: Sat 18 Feb, 2012 7:55 pm
by gwagensteve
Maybe.

Check that there's no play in the wheel bearings or kingpins before you start. If there is, then you need to go for the full kit.

Steve.

Re: Leaky CVs

Posted: Thu 12 Apr, 2012 1:55 pm
by luigi
Great information. I also have a leaky seal in my front axle. Thanks.

Re: Leaky CVs

Posted: Tue 08 May, 2012 11:42 am
by bunnyblaster
Good-day Brad,

Did you manage to source the seal only? I have the same problem, but don't need king pins or bearings.

Cheers

Chris

Re: Leaky CVs

Posted: Tue 08 May, 2012 12:42 pm
by jonfromhamilton
I sell seals.
give me some sizes and I can tell you if I have anything.

Re: Leaky CVs

Posted: Tue 08 May, 2012 1:13 pm
by Brad.Jones
bunnyblaster wrote:Good-day Brad,

Did you manage to source the seal only? I have the same problem, but don't need king pins or bearings.

Cheers

Chris
No I ended up getting brand new CVs and a full knuckle rebuild kit for both sides.
More than I needed but I have got a few spares now.

Re: Leaky CVs

Posted: Fri 11 May, 2012 2:06 pm
by bunnyblaster
Steve, how much King pin play is too much?

I have no wheel bearing movement, but there is movement in the king pins.

The wheel bearings were tightened but not replaced in 2007.

I am trying to work out if it is worth doing the complete reco or just change the axle seals.

Thanks

Chris