DMCH Lower ball joints IS THIS WHY THEY FAIL??????

[bozzzydmc]

I have a new set of Special T ones here ... and I've had them quite a while .. based on what ive gleened it seems that they have changed supplier since these were purchased

After examining them last night the grease is fresh and the circlip groove is cut correctly with no blueing of the metal etc

I cannot see any grease channel on the ball joint itself, unless its out of view ...?

These are on there way to a club member now .. but i wouldn't hesiate installing this pair on my car

[bandit]

One of the many....... etc etc. Cheers Mike

[tourettes tony]

This is interesting.

What you were saying about the taper of the special T ones does have me worried and I might convert to these esprit ones too. How much does the diameter vary between oem and esprit?

I've just been looking into this and think the partnumber is actually TC163. Any chance you could send me one of the oem joints? I want to modify a pair of these and try them out on my car too.

oh no, look what you have done now

[A Van]

Worth bearing in mind that I haven't heard or read of any premature wear or failures with SpecialT........yet

[Dan 6511]

True but 'if' the taper isn't correct then I want them out, I'm not having it held in just by one nut.

[Phil349]

Mike, maybe the ones you have are different to what I had if yours are older ones, who knows they may be different. Maybe that explains it, I dont know, but I also have not heard of any failures with the special T ones after a lot of searching around.

I have looked at the box I have for the esprit joint and it has both part numbers on it, Delphi Lockheed AK40D and TC163 so you have found the right one Dan. I cant remember now exactly what the diameter difference was, it was back in december, but it wasnt excessive, I think we machined off about 1.5mm off the diameter or there abouts. Then knurled them.
The special T (1960's VW beetle) ones you have are the right diameter, so if you go for the same size when modifying the esprit ones you should be fine.

Some of my pics have dissappeared off the post from last night, if anyone wants them for reference they are here:
http://postimage.org/gallery/11yu263oo/

Darren, if you PM me your address ill send the special T ones over if you like?

[Admin-bloke]

Thanks for sharing all this Phil, it's definaely appreciated

[tourettes tony]

i only have one concern about the press fit with the collars, what happens when you have to remove them and replace them, the splines will be mullered where do we go from there

[willinot]

Mine was one that failed as well. According to dmch it was a different failure as on mine the nut sheared off the threads totally cutting through the split pin.

All the same, I then changed over to the orignal ones from Dave H.

[dmcjohn]

Hi Phil,

Great work, and great idea to go after the Esprit ball joints.

Rather than machining the ball joint though, I'd prefer to modify my lower control arms to suit a standard ball joint. The splined collar on the control arm through which the ball joint passes can be easily removed and replaced with one suited to the Esprit ball joint.

If this was done, it would avoid more machining of ball joints everytime it needs to be replaced.

What do you think?

thanks,
John

After what was detailed in this thread about the special T auto ball joints:

viewtopic.php?f=20&t=1792

I did some research to see what else might be available and might work and decided to order a Lotus Esprit lower ball joint (also same as used on the mk1 astra) to have a look at and found it looks more or less spot on, correct casing height, thick base like the oem joint, the tapered shaft is correct, etc. Only thing is they are a little to big in diameter and dont have a cir clip groove.
I had it modifed by machining the casing down to get the right diameter (doesnt need much taking off though), obviously this removed the knurled finish so that was put back in after the machining, cut a groove for the cir clip to fit into and drilled a hole in the shaft for the split pin. This all worked out fine and all dimensions matched the OEM joint, the tapered shaft fits the hole in the steering knuckle very well, significantly better than the special T joint.
I was a little concerned about the stregnth compared to the OEM joint as its an unknown and attemped to stress test it, but without access to specialist equipment I could only put 1.5 ton of force attempting to pull the shaft out from the socket through the ball joint, both joints take this fine. It would be better to test it further but I had spent long enough on all this and wanted the car back together! And seeing as the design of the ball joint is right and the esprit suspension puts force on the joint in the same way as the deloreans suspension does I felt it worth trying.
I got another two ball joints had them modified in the same way and now have them on the car, so far, roughly 1000 miles of use later and they seem fine still. I will be checking it every so often in the same way Darren has said though.
They come with Nylock nuts but ive used castle nuts instead. And i mean proper sized castle nuts, not the low profile ones you get with the special T joints!

Here are some pics, shown after pressing into the lower arms. After these were taken cir clips were fitted as normal, the joint packed out with bearing grease and boots fitted.

These joints are made by Delphi, part number AK40D.

Its a little work to use these but I feel better using these than the special T or DMCH ones to be honest. But I do understand the special T ones have worked and are still working for a lot of poeple just fine and thats great, but its down to what each person feels comfortable with at the end of the day.