It sounds like your top plate may have been swapped for you. Worn rails or slots they ride in may be the cause of the slop in your shifter. The top plate can be pulled from the interior by lifting the carpet and pulling the doghouse cover if you don't want to pull the transmission to inspect. Another possibility for the slop is a worn stub shaft.

Replacement top covers can be found but will require some searching.

I just acquired a Core shifter for my upcoming trans swap to M5R2. It seems like a nice piece and the reviews on some of the other forums were positive. Depending upon what is worn in your shifter plate it may be of no help to you.
https://core-shifters.com/collections/shifters-for-f150

Good luck with your truck.
Jonathan

 

I would carefully inspect the work where the bolt holds the shift lever. I always had trouble getting that tightened up properly. One time i thought I had it installed properly and I drove somewhere and the shift lever was loose do to my improper installation even with a new bolt. That may not be your problem but the bottom line here is carefully inspect to see where the problem is.

 

i love my core shifter

 

It's good to hear another positive review. Have you had it long? Any issues? I'm looking forward to shifting gears again and want firm, decisive shifts.

 

https://www.f150forum.com/f89/core-h...hifter-459925/

the shifter has been in since last fall..so its been used for a few thousand miles now. its definitely a legit short throw all metal shifter. you will certainly get your firm decisive shifts.
the only real drawback to me is a slight rattle sound at the upper rpms in 3rd, and most of 4th. goes away in 5th or if your hand is resting on it. all other times it produces a satisfying gear/bearing rollover hum..
of course with this type of shifter you will have increased physical effort to shift, but much less movement required. it will break in a bit, and the unit appears very well made.

 

Thank you for the replies. I'll look at the stub shaft first and then the top plate.

 

I was able to take a look at the shifter more closely this past weekend. I didn't take off the top plate, as that's for another day when I have more time and if I need to replace it. This exercise, while aggravating, reminded me that I had taken off the cover to install a new gasket and plugs, as it was leaking a bit. I looked at the portion of the top cover that I can see under the shifter, and there was more oil reside than I had expected. I did find a place, Midwest Transmission Center, that sell rebuilt top covers if needed.

I removed the bushing and shift stub and played around with combinations to see if I could identify the reason for the slop. The slop has created a scenario where the busing and pins are getting beat up from the movement of the stub. The top bushing, which was installed ~5K miles ago, is broken. So there's a little play inherent due to those situations. Separately, I installed the shift stalk on the stub with the wedge bolt, and it was as tight fit. I didn't even need to tighten it to learn that. Then I dropped the stub back into its slot and noticed what I thought to be more side-to-side movement than I previously remember. If I remember correctly, the flat blade of the stub was seated pretty well against the spring loaded pins that return the shifter to center. The side-to-side motion is from the 3 and 9 positions. Because of the movement allowed, there is is a slight amount of rotational movement due to the slots in the stub that ride along the bushing. Again, this slight movement might be because of the worn pins I noted earlier. The image attached is a screen shot of a video I found online.

All this taken into context, how much side to side movement should a sift stub exhibit? I'm not familiar with how a top cover rebuild / change could possibly fix my issue. The only area that I see could impact movement is the slot into which the stub sets. I'm not sure how much adjustment, if any, this area has. That is, can the space be closed up? Lastly, do stubs wear? My truck only has 123,600 miles on it, and the engine and transmission aren't beaten by any means.

Thanks in advance for any inputs. It's just frustrating when I had it working so well right before the clutch change. All I had to do at that time was the bushing replacement, and seeing as that didn't return it back to normal, something else has changed.