Recommended -- Rodney Dickman's Rubber Bushing Dog Bone

[TopNotch]

When I first got my yellow car, the dog bone (engine torque strut) in it was in very bad shape, and the engine flopped around like a fish out of water. So I got a nice new polly bushing dog bone for it. But there was a problem with it. It is so stiff, that when you go from acceleration to deceleration, or vice versa, without pushing the clutch, the gears "bounce". Sometimes it could be pretty bad.
Recently I replaced it with one of Rodney's new rubber bushing dog bones...

Except that the picture shows a V6 dog bone (below an original), but you get the idea. The car rides much better now. So if you have a manual transmission car, and you need a new dog bone, I recommend Rodney's rubber bushing dog bone. For an automatic, it's not that important, and you can use either rubber or poly.

[GTRS Fiero]

The OEM look dog bone.  There is an upcoming article comparing the various dog bones available.

Interesting.  The automatic transmission coupled with a poly dog bone is supposed to be worse than a manual.  I have the poly dogbone, with poly engine and transmission mounts.  The vibration isn't bad--even at idle.  Mine is a V6, though.  I will say that you feel it if the engine isn't running right.  The only complaint is harmonics at 45MPH and 60MPH.  The harmonics may or may not be related.  I have run poly dog bones for years.  I have tried all the poly dog bones I've seen offered.

I was told that I'd hate the poly engine and transmission mounts, but so far, so good.

Since you have this rubber dog bone, I'm curious how you like the adjustable slots?

[Raydar]

...
So if you have a manual transmission car, and you need a new dog bone, I recommend Rodney's rubber bushing dog bone. For an automatic, it's not that important, and you can use either rubber or poly.

Don't forget, the later (86?-88) automatic Duke cars have that goofy "uni-mount" on the end of the transaxle, instead of the front and rear trans-to-cradle mounts.
When I had my automatic Duke, the (admittedly tired) rubber dog bone bushings would allow the air filter housing to smack the trunk wall, under acceleration. Poly bushings took care of it. Fresh rubber may have, as well.
Edit - On second thought... I'm not sure what kind of bushings I used. That was 20 years ago.

My latest manual Duke car seems to be fine. I haven't replaced any of the mounts or the dog bone. Probably still rubber. I'm guessing not original, though.

[TopNotch]

Since you have this rubber dog bone, I'm curious how you like the adjustable slots?

? There's nothing adjustable about my dog bone. Didn't need to be -- it fit right in.
BTW, Rodney's rubber dog bone is stiffer than stock, but not as stiff as poly.
My 88 duke car has two mounts on each side (fore and aft) of the transmission, and one big one under the engine.

[GTRS Fiero]

Ah, sorry.  You just have the rubber dog bone--not the OEM look rubber dog bone.  The OEM look dog bone has slots, and is available for either manual or automatic, but only for the V6.

[Raydar]

...
My 88 duke car has two mounts on each side (fore and aft) of the transmission, and one big one under the engine.

Same as mine.
The automatic setup makes no sense to me. Required a whole different cradle (has a shelf welded on the left side rail) and a special bracket that wraps around the end of the trans. More complexity and additional inventory, for a less secure mounting method.
That's GM for ya'.

[GTRS Fiero]

The cradle is different for different transmissions?

[Raydar]

The cradle is different for different transmissions?

Sort of. The Duke/automatic cradle has all the mounting points for any other engine/trans combo. Any and every Fiero engine will bolt to it with no problem.
It just has an additional shelf welded to the left side rail. I've got one, but it's in storage. Next time I go, I can get a pic.

[GTRS Fiero]

A pic.  Yes, please.  Next time I look at a Duke, I'll have to check out the mounting more closely.