SAS steering - heims vs. TREs
 

What are the pros and cons of using chromoly heim-joints for steering linkages (drag link and tie rod) versus tie rod ends? Are heim joints street legal? Also, I've seen misalignment spacers come with the heim joints... what exactly do those do?

Heims:

Pro's: flexibility, variety, used correctly stronger.
Cons: subject to contamination and faster wear.

TRE's:

Pro's: longer life under typical under-vehicle conditions especially offroading.
Con's: limited configurations and range of movement, generally weaker especially under certain stresses.

Misalignment spacers allow the Heim ball to rotate a greater range inside the cage (or vice-versa, lol). Imagine in the shot from my track bar below, that the bracket was bolted up right up against the side of the ball.

http://memimage.cardomain.net/member...4_438_full.jpg

Those spacers on either side of the ball in this case do two things. The cage can rotate with greater freedom around the ball without hitting the bracket, and also here they reduce the 5/8" hole to 1/2" for my bolt.

There is another type of spacer called a cone spacer. It is simply a thick washer that is flat on one side, and beveled or "coned" on the other side. You use these typically when stacking heims say on a spindle arm where the drag link and tie rod join the spindle using one bolt. I'll find a pic of that for you and one of a cone spacer.

They are also used on link arms for 4-links and so forth.

Here's a heim jointed drag link (on top) and tie rod (on bottom). Note that the drag link has the cone spacers to allow a lot of articulation. The tie-rod doesn't need it since (hopefully) the axle doesn't bend.

http://classicbroncos.com/img/stonecrusher8.jpg

I would use TREs on the tierod and heims on the drag link IF you have some angle on the drag link already and your setup has alot of articulation. Otherwise 1 ton Chevy TREs all around

Only problem I have seen with the Chevy TRE's is using them in an inverted-T steering setup where the draglink fastens to the tie-rod instead of the knuckle/spindle. The hole in Chevy TRE that some folks use to fasten the drag link is actually for mounting a steering stabilizer and it's not very strong when used for the inverted-T steering setup. They do break and there's plenty of talk about that.

If you're not an extreme wheeler you might never encounter it, but if your goal is a very strong steering setup for instance, you might consider using the Chevy TRE's only in a crossover setup, not inverted-T.

Sorry I should have specified but you dont have to buy that one chevy tre. Just buy one like the other 3, make sure your thread is right.

I'll be using a crossover steering set-up with both the drag-link and tie rod attaching to high-steer arms. Hopefully I'll be able to make some sweet low-sitting coil suspension eventually to keep my drag link angles down, but I may be on leaves for awhile.

It sounds like I could get away with TREs on the tie rod well enough, which is good. It also sounds like it would be beneficial to have a heim joint at the knuckle end of the drag link. I have a toyota IFS power steering box, so I will either use a toyota TRE at the pitman arm, or I will perhaps ream the pitman arm out to use a Chevy TRE. What do y'all think? Would it be better to have a heim at the pitman arm also? What would be the best way to attach a heim to the pitman arm?

The pitman are is as good a candidate for a heim as any. If you put TRE's anywhere it should be the tie rods since they are low down and get contaminated a lot. This is the only reason not to use the relatively small heims (as opposed to the very large ones often used on 4-links) down low. Small ones wear out relatively quickly in this service if you get them dirty and/or wet much.

But if you decide to use heims everywhere else, you can either bore out the pitman for a bolt and a heim, or do the hybrid setup like you described.

You can get yota pitman arms will all kinds of holes in them, the stock one wont work with a crap anyway since the ball joint is pressed and welded in there. Sky Manufacturing has several options and will make you whatever you want. Dont use the Yota TRE they are small and weak unless you use their Fj-80 (I think) TREs.

Good advice guys... thanks!