Inner CV joint replacement

[Groove]

I expected there to be heaps of posts on this already, but couldn't find much from the search (perhaps it doesn't accept two-character search terms).

Anyway the car's just had it's 190,000km service and apparently the inner CV joint is on its way out on one of the sides. I see they are quite cheap on eeuroparts (approx $40US) so I am considering doing it myself. Are the instructions in Bentley sufficient? Does anyone have extra tips or hints about doing this for a first timer? Are the eeuroparts inner CV joints sufficient quality?

On the original inspection of the car, they mentioned that the inner driver was leaking grease... could this have led to the demise of the CV joint?

Cheers.

[jefspg]

I have a website that goes into replacing the CV joints.
Check it out!

http://www.twinsaabs.com

[Groove]

I saw it Jeff, thanks. You took the whole thing apart though and I only want to do the CV joint! Surely I don't have to remove all of that stuff...

Also what I believe to be the "inner CV joint" you are referring to as the "bearing" - are we on the same page here? There was something else you called the CV joint but it appears to be what eeuroparts call an "outer CV joint". I'm not experienced enough to know.

[ProfZ]

What jef refers to as the "tripod joint" is the inner CV joint.

You will have to remove the entire axle to renew the tripod and its boot, but I never remove the whole knuckle: Just disconnect the tie-rod end, and undo the bolts for the upper ball joint. Pull knuckle outwards, being careful not to strain the brake caliper's hose. This'll give you clearance to tap the splined end of the axle out of the hub bearing, then you can undo the tripod joint's boot clamp and withdraw the axle.

One word of advice: If the tripod joint has seized, it may have carved ruts into the inner driver (the 3-lobed "cup" into which the tripod fits). Feel for these ruts with your fingers, and replace the inner driver if you can detect a rut. The ruts will cause vibration when you accelerate.

[900 spg]

Hi,
does anyone have the part numbers of the correct tripod and cup as there seems to have been two sizes depending on MY and engine and gearbox.

I have a 1987 spg and I am sure I need one or maybe both of these.

I have also written before about being unable to remove a cup from a gearbox I have in my garage. It is stuck in such a way that taking it out is completely impossible. consequently I cannot take the gearbox apart and rebuild it.

Any ideas, thoughts, etc welcome.

Thanks for the info.

best regards

Dusan

[Groove]

Thanks for hijacking my thread Dusan! No seriously... have you tried punching your car year and model into the eeuroparts.com website? That should give you the right part number.

ProfZ: the joint hasn't seized, I'm still driving on it and it is only in the early stages of wearing out.

I've just opened my Bentley manual (was at work before) - it looks like a fairly comprehensive walkthrough. Would this be a good time to change my front shocks and springs if I am doing the inner CV joint?

[900 spg]

Hi Groove,

Sorry that was not my intention. It was pretty much related. I remember reading about different sizes fitted on different cars which were the same models for the same model years. That's why I asked.

As to cup removal, if you want to change these as well this is the problem I had and still have i.e. not being able to remove one of the cups from the gearbox (differential to be exact).

Good luck

Dusan

[arobinso]

Hi Groove, what were your symptoms for the inner CV needing to be replaced?
The inspectors told me that mine is leaking grease and I can see a small crack in the boot. I'm interested in this thread to figure if I should get a new boot and pack it full of fresh grease instead of waiting for failure of the tripod bearing.

[woywitka]

considering it is close to the same amount of labour to replace the boot as it is to replace the joint that really depends. But what u can do is, to prolong the life of the leaky joint you can do a split style repair! like $15! i understand the inner drivers aren't as prone to split style boot failure, compared to the outer drivers for some reason. You also should consider if it is worth dooing the whole axle, trip pod and outer c/v at the same time if your outers are old!

[cdaly]

Originally Posted by woywitka

inner drivers aren't as prone to split style boot failure, compared to the outer drivers for some reason.

Reason is the outer CV joint boot has to flex the full angle of the steering (about 120 degrees) while the inner has only to flex for the up/down movement of the suspension which is only a few degrees at most.

[arobinso]

Ok, seems like you can't search:
"cv AND boot AND split AND repair", but
"cv boot AND split AND repair" works fine.

Looks like injecting grease and the split boot repair kit method is not too highly regarded on the following link. I'll have to investigate more.
http://www.saabcentral.com/forums/vi...t+split+repair

[Groove]

Originally Posted by arobinso

Hi Groove, what were your symptoms for the inner CV needing to be replaced?

The car is having some vibration at 80-100km/h. I had no idea what it was but I got the mechanic to check it out at the same time as the service and they told me it was the "O/S Inner CV Joint" being badly worn.

[Groove]

Originally Posted by arobinso

Ok, seems like you can't search:
"cv AND boot AND split AND repair", but
"cv boot AND split AND repair" works fine.

If my theory is correct and the character limit for the search is 3 or more, then your top search will bring up nothing from 'cv' and cancel the other search results out since they are ANDed together.

[ProfZ]

Originally Posted by Groove

the joint hasn't seized, I'm still driving on it and it is only in the early stages of wearing out.

I know from experience that you can drive for quite a while with a seized tripod joint (resulting from a broken boot and loss of grease), and all you will feel is vibration.

The vibration you get is either due to one (or more) of the tripod "wheels" breaking up and losing needle rollers, or to wear in the inner driver "cup" caused by underlubricated (or seized) wheels scraping ruts into it.

The tripod boot on the exhaust side of the engine usually ruptures first, due to chemical breakdown from oil dripping from the cam cover and heat from the nearby exhaust downpipe.

I do not advise using split-type replacement boots: It's almost impossible to seal them up adequately, and the seams don't hold together very long.