727 Shifts Down to 2nd at highway speeds

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With the right parts, it will work just fine.

>One thing no one mentioned is that the vacuum advance plays a very big role in your throttle position while cruising. Typically, the SBM engine will want upwards of 50 degrees, perhaps about 56*, to cruse with. If you don't give her what she wants, then the throttle ends up being too far open to supply the required power.
>Your stud on the throttle arm is too close to the pivot point, which means that you think the throttle is barely open, at cruising speed, but really the throttles are in the normal position/only your gas pedal is not. This will change when you install the proper parts. And it will change the operation of the KD mechanism as well.
> the slot at the front of the KD rod has a dual function. The first has already been mentioned. The second, is to provide the primaries enough travel to drive normally without constantly jumping between gears. Your cobbled-up linkage has defeated this function.
> yes you could drive 100,000 miles with no KD linkage at all, and not damage the trans at all; all you gotta do is drive on the primaries only, and stay in the short window provided by the factory adjustment. So, if you do, for testing purpose, remove the KD rod, remember; Easy does it!
 
You are so wrong! The rear end of that slot in the arm must be keep up against the throttle stud with a spring. So the rod follows the throttle stud with every movement. End of story!
CudaFactHackJob said:
You can run a TF without the KD hooked up and not harm it at all. If you notice, the rod has a slot that allows the carb to open without affecting the KD arm. If you never go past that point; there will be no damage. IF you think you have a low fluid problem, add another quart. If it's too much, drain it out the neutral safety switch.
Click to expand...
 
The linkage on the torque flight is actually called throttle pressure. It increases line pressure as you open the throttle. It is important for durability of the trans. If you have the linkage hang up at full pressure it will shift very hard into drive and reverse. The upshifts will be late and downshifts early and hard. You can drive it with it unhooked to test but go easy.
 
You really should get your hands on the factory service manual. The trans section will take you through the whole thing. It is a very simple and durable trans.
 
I think I have fixed the issue. I added another quart of fluid to the transmission and it appears to be driving fine. I havent had a chance to drive it extensively though due to the cold weather and salt on the roads. Will find out when the weather gets a little warmer and post on this thread then. Thanks for the help so far.
 
AJ/FormS said:
With the right parts, it will work just fine.

>One thing no one mentioned is that the vacuum advance plays a very big role in your throttle position while cruising. Typically, the SBM engine will want upwards of 50 degrees, perhaps about 56*, to cruse with. If you don't give her what she wants, then the throttle ends up being too far open to supply the required power.
>Your stud on the throttle arm is too close to the pivot point, which means that you think the throttle is barely open, at cruising speed, but really the throttles are in the normal position/only your gas pedal is not. This will change when you install the proper parts. And it will change the operation of the KD mechanism as well.
> the slot at the front of the KD rod has a dual function. The first has already been mentioned. The second, is to provide the primaries enough travel to drive normally without constantly jumping between gears. Your cobbled-up linkage has defeated this function.
> yes you could drive 100,000 miles with no KD linkage at all, and not damage the trans at all; all you gotta do is drive on the primaries only, and stay in the short window provided by the factory adjustment. So, if you do, for testing purpose, remove the KD rod, remember; Easy does it!
Click to expand...

Can you explain what you mean by 56 degrees?

And what proper parts are you referring too?
 
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