Why do I keep breaking Tarrett drop links?
 

Today I was in the middle of a spirited drive on Mulholland. When making a left, I heard a pop. After stopping, I looked under the car to see a broken drop link. I have had 2 '87 3.2s and with both I had Tarret drop links fail. I am familiar with how to set them up so there is no preload, but still this keeps happening.What am I missing? Anyone know a possible cause??

Photos would help, especially a closeup of the break itself.

Same point of failure on two different cars. Co-incidentally both happened on the same stretch of road while cornering.
http://forums.pelicanparts.com/uploa...1629760244.jpg

You are probably binding the joint and braking it. Have you check that the drop link can move with out binding through out the range of suspension travel?

Please elaborate, are you speaking of the bearings?

As the suspension moves up and down, the drop links move and the rose (heim) joints move to compensate. If the rose joints bind, something has to give......

Looks like you have them upside down

Not as far as I know.

http://forums.pelicanparts.com/uploa...1629773097.jpg

That piece that the red arrow points to is for the spring plate, not the control arm.......and that rose joint the red arrow points to has severely limited movement because you mounted it wrong....you need misalignment spacers on each side of the rose joint.

not sure about that either:

"The Tarett adjustable drop link we are using has the ability to be attached to the swing arm or the banana arm. When installing in the swing arm the included eccentric nut/spacer will replace the eccentric nut in the swing arm. This nut is used to set the toe adjustment in the rear suspension. Installing the drop link in the swing arm will give the sway bar a little softer feel. Also, if you install it in the swing arm you should get the alignment checked after installation to insure proper toe in. Follow these steps for adjusting preload after installing in the swing arm."

Fine. Do it your way and break stuff...I am done.

Not my way, I'm just quoting Wayne Dempsey. If that's not correct, I would hope that he and Pelican would update their information.

As Winders mentioned, you have it installed incorrectly. Missing the misalignment spacers.

http://forums.pelicanparts.com/uploa...1629774753.jpg

Ball Joint Rod End Washers. You need 8 washers in total in 12mm size.

Winders and Solamar are correct regarding the incorrect setup.

https://www.mcmaster.com/rod-end-inserts/

Interesting, although none of the sets of Taretts that I have bought come with those spacers. Wayne Dempsey recommends the ecentric be used as a spacer, in my (latest) case a mechanic replaced the eccentric with washers, but that seems to have been sucessfull for some on this board as well (see below from another member's post.) What I am saying is, there is a lot of conflicting information and understanding about the install of these. Just trying to sort this out... no need for anyone to get upset.

http://forums.pelicanparts.com/uploa...1629776976.jpg

Thanks Paul, I understand the benefit of the washers, and what you are saying makes sense, but also, you're saying the Taretts cannot be installed as delivered? No problem if that's the case, but it seems like that would be a major oversight by Tarett. They certainly don't come with those washers.
I will send an email to Tarett and see what they have to say.

Yeah, I totally understand. They can be installed as delivered, but unfortunately to get the best use out of them you have to modify them - most of the Pelicaners who have these end links use regular washers to increase the range of motion and reduce binding. Also, get slightly longer bolts to compensate for the added thickness of the washers (4 washers per end link). And don't use the adjusting cam unless you are installing the links directly to the spring plate. All you need are the 4 bolts and washers, the 8 McMaster washers, and the end links.

I hope those washers fix your problem. Cheers!

As delivered, the Tarett rear bar is meant to be installed with the drop link attached to the spring plate. If you want to attach it to the trailing arm, you need to buy additional hardware. Specifically, what Solmar shows in his photo.

Those washers Will NOT FIX THE PROBLEM!

Relax there, guy.

The spacers worked for me, and I drive mine pretty hard on AX on weekends. If you think the misalignment spacers will solve the problem, then by all means. The McMaster link also has the spacers as an option as well. Solamar's image has both the washer and the spacer.

If your mechanic is the one who installed it this way, you might want to consider whether he's the right one to work on your car. I don't mean to come across as harsh to him, but the way it's installed in the picture you posted shows a misunderstanding (installing the eccentric bolt as a spacer, causing the binding) of how these parts should work.