A section of the linkage has, for the lack of a better term, a turnbuckle. One end has LH threads the other, RH threads. Anyone which end is which?
Original Post
...Damn Good Question!

The Internationally Recognized Designator for a Left-Hand Thread, is a Groove Cut All The Way Around the CENTER of the Nut.
I just went out and Checked on 'MY' Kat...it was the Nut Towards the REAR of the Pantera.

So...Wrench it CLOCKWISE as if to TIGHTEN (a Right-Hand Thread), and the Left-Hand Thread will come LOOSE!
Last edited by marlinjack
Marlin -

That's a really good tip. I never knew that.

You can see the groove cut in my nut... To the rear as well.

(Thank Gawd I don't have grooves cut around both of my nuts! Then I wouldn't know which way to screw!) - Sorry for the 6th grade humor....

Thanks -



Images (1)
...We All can use a Little Humor.

Thanks for the Photo.

As One can see...Just the 'Sharps' are Cut. The Groove Does Not Go Into the 'Flats'!

Left-Hand Bolts? That's Another Story!
here is a photo I took this AM (I have been blocked from site till now).
I worked a lot of turnbuckles so I could see (and know) which thread was LH before I tried.
besides the marked nut, It appears the shorter rod is the one threaded LH for mine

the manufactor I worked for did not used international designation as the LH nuts on the linkage I worked for 40 years were not ORIGINALLY marked. (they were after I adjusted)

AND if my access capibility continues, I wont be able to see my post


Images (1)

That's the same as the way mine is set up.

One splined connection with a U-joint in goes to the ZF (the short one) and the U-joint goes into more linkage (the long one).

You can adjust both the length (which gives you full gear engagement) and the "side-to-side" position with this turnbuckle.

If your shifter is hanging up on the fingers, or is not going fully into gear...

It's a tricky adjustment, though. There can be a lot of trial and error.

I believe it does.

I know a loose trunion bushing will result in the ZF popping out of gear....

I believe lower is better, but I have only adjusted one of them...



PS.... After reading Bosswrench's reply below, I did want to update this post. I agree with him that the only way you can do this adjustment is if all the shifter linkage is removed from the car, and then you soak the nuts / threads in Liquid Wrench or equivalent, and use vices, and big wrenches to get the 40 year old connections apart.

I was not able to break any of the nuts or the turnbuckles loose with the linkage connected in my car - I just slid the U-Joints on the splines shafts....
Last edited by rocky
Brother-bee, when you start fooling with the shift-shaft trunnion, there are a number of clearance areas you need to watch simultaneously. There's a channel in the left motormount that the shift rod slides through with little clearance, and an adjustment coupler that gets very close to the edge of the inner rear fender on one side and the bellhousing on the other. Plus, when the height of the trunnion is changed very much, the total length of the dog-legged shift-shaft also changes, which can cause popping out of gear if some are selected. These maladies can accompany a bad rubber isolator in a motormount, too, making diagnosis complicated.

If the trunnion is loose of course, you really have no choice but to adjust it, and the length change can be adjusted for quite a bit using the splined end of the last u-joint rather than loosening the big adjuster. On our car, I was never able to loosen that adjuster- it takes ZF removal to get big enough wrenches in there, and so far, I've always forgotten when the box was out. Finally, if you have one, be very careful with the popular aftermarket aluminum-and-teflon trunnions. That area gets awful hot while running and teflon softens at low temperatures. The teflon bushing sometimes softens enough to slide past its setscrew and out of position, suddenly making shifting very difficult. Very hard to repair on the road with a smoking-hot engine.
One of the first parts I replaced was the stock trunnion and rod from the shiftier with all stainless parts from Pantera Performance in Co.
Trunnion height is very important, but you should never have to adjust the rod, between the trunnion height and the splined end you should be able to dial it in.

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