Hi there! I recently drove a 76 Buick which is very similar to my 75 Grand Safari and I noticed a big difference with the shift lever. My one is sluggish to move compared to the Buick. I can go through all gears, that's why I don't think there is something wrong with the linkage rod. I guess something at the steering column is causing the problem, but my manual don't say a word about it. Any ideas how to fix that or where to look at? Greetings from Germany!
The various linkages always need lubrication, but how many lubricate the column shift tube, let alone the steering shaft bearings? Also, the transmission's manual valve may be a bit worn, so it sticks.
So, i checked the shift linkage but it's a solid linkage without bearings. The manual valve is inside the gearbox, isn't it?
It is. You should be able to unbolt and fully detach the linkage to the manual arm; do so, then move the shifter lever, see if it really the culprit or the transmission's manual lever and valve.
X2 on disconnecting the linkage from the trans, that will allow you to also move the shift lever on the trans and compare it to how it feels with the linkage attached. Also a lot of the old GM column shift linkages use plastic bushings in several placed where the levers attach. They usually wear and fall out and you may not know they are supposed to be there. Also there can be adjustments in some of the linkage rods. I have never owned a 75 full size Pontiac, so I do know know the specific's of your linkage. So pictures could help/
I'll take some pics, but that may take some time. Here is one from the manual for full-size cars...maybe that's a good start.
If there's undue wear, I would point out between 1 and 3, as there is no bushing that goes between the end of the rod and the holes it goes through. Does your shifter feel like it has drag all through the motion, or that it feels 'stuck' then suddenly moves?
That's really hard to answer. I would say stuck then suddenly moves after the lever exceeds a specific point.
Yeah, that sounds like the parts are so worn, they're catching on each other, then "pop" past when you finally get the shifter to move. Those two parts I indicated would be your starting point in inspecting the linkage.
Ok, here we go with some pics...it's the best i can do alone in the dark garage and without jackstands. Is that really the way it should be?
Look at the first picture; the upper left corner is a 'cup' that is either bolted or welded to the frame. It contains a bushing and the spring, visible on the shaft. the cup is supposed to beset so the shaft end comes straight through. I think it's bent enough to be allowing the shaft to 'drag' inside the hole, and/or the bushing is missing. If you look at the diagram you posted up in post #6, it's items 5 and 6 (#5, flat washer and #6, bushing) that appear to be missing.