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Thread: Seat "Sliding" vs "Rocking"

  1. #1
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    Seat "Sliding" vs "Rocking"

    Am I the only one confused by the terminology? I feel like people use sliding and rocking interchangably here.

    To me, sliding and rocking are two very different things. I've replaced 4 sets of seat bushings and that always cures the sliding issue. The rocking like a rocking chair however, I'm still dealing with. I've tried the "shove a penny between the rail and the bottom of the seat fix" but that hasn't solved my problem. I can still feel some play when I lean from front to back. Do I just need to take the seats out and tighten every bolt I can find under there?

    The seats in these cars just seem flimsy to me. Anyone else agree?
    Cooper
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    '02 Topaz 3.0 (2009-2020)
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  2. #2
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    There's definitely something still up with my driver seat that I would attribute to rocking. This after replacing all rail bushings with tight fitting Whalen bushings. Haven't begun to try to figure out what's up. I'm seriously considering just putting some Recaros in there and calling it a day.

  3. #3
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    Allow me to join the rocking seat club lol ... this past weekend I decided to tackle the seat rail bushing replacement, and to my surprise, they had already been replaced, and there was no play whatsoever on the part that holds the bushings in place (they appear to be the Whalen bushings). This left me confused, and then after much analysis I realized that my seat doesn't slide front to back, it rocks slightly.

    Has anyone figured out what to do about this? Also, what's the "penny" fix mentioned above? I've never heard of it.

    Thanks!

  4. #4
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    I've seen both (rocking and sliding). The passenger seat simply slid fore and aft, but no differential motion (rocking). Whelen bushings fixed it. The driver seat did both. Whelen bushing solved the sliding motion, and some of the rocking motion. The rest was fixed by replacing the sheared off bolt at the left rear of the seat which held the frame to the seat. Now both seats are rock solid.

  5. #5
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    Quote Originally Posted by gmushial View Post
    I've seen both (rocking and sliding). The passenger seat simply slid fore and aft, but no differential motion (rocking). Whelen bushings fixed it. The driver seat did both. Whelen bushing solved the sliding motion, and some of the rocking motion. The rest was fixed by replacing the sheared off bolt at the left rear of the seat which held the frame to the seat. Now both seats are rock solid.
    I wish I would have checked for this while I had the seat out...oh well, time to take the seats out again. Is there any specific position the seat has to be in, to access the bolts? (Ie: all the way back, all the way forward, etc).

  6. #6
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    Quote Originally Posted by MCoupeStud View Post
    I wish I would have checked for this while I had the seat out...oh well, time to take the seats out again. Is there any specific position the seat has to be in, to access the bolts? (Ie: all the way back, all the way forward, etc).
    Looking at the pics I took while working on them the last time: I suspect it doesn't matter, ie, there's enough clearance to get a socket and ratchet in there either way - though for the record, from the pics, it looks like I had the seats all the way rearward when I pulled them.



    The one on the left was missing its head. There are two matching bolts at the front of the seat.

  7. #7
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    Quote Originally Posted by gmushial View Post
    Looking at the pics I took while working on them the last time: I suspect it doesn't matter, ie, there's enough clearance to get a socket and ratchet in there either way - though for the record, from the pics, it looks like I had the seats all the way rearward when I pulled them.



    The one on the left was missing its head. There are two matching bolts at the front of the seat.
    Excellent...thank you! I feel confident now that I know what I'll be looking for!

  8. #8
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    Quote Originally Posted by MCoupeStud View Post
    Excellent...thank you! I feel confident now that I know what I'll be looking for!
    It would be interesting to know how many with "rocking" seats have met the same fate as my Z, ie, customer (in this case prev owner) goes to mechanic and says the seats are sliding around; the mechanic, not a Z mechanic and knowing nothing about bushings etc, assumes that means that the seat (mounting) bolts are lose, and wanks on them... to the point of torquing the heads off them [actually in two stages: customer tells mechanic that the seats are lose, mechanic "tightens" the bolts, or finds them already tight, gives the car back to the customer saying he fixed them, the customer comes back and says the seats are still lose, so the mechanic really "tightens" the bolts, torquing off the head of one or more]. That's the only way I can imagine the head got torqued off one of the bolts on the driver's seat. [and actually, the rocking and sliding, was one of the reasons that the PO sold the Z - the mechanic after "tightening" the seat bolts, told her that the only answer was a new set of seats, ka-ching, $2000... at that point she gave up and I bought it for a song.] The other four Z owners in town that I'm friendly with - not a one knew anything about seat bushings, but very much knew about the sliding; and likewise sadly, didn't know about the popping welds of the trunk floor. My impression is that there a those (few) mechanics that know/understand Z's, and then there are the rest.

  9. #9
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    Quote Originally Posted by gmushial View Post
    It would be interesting to know how many with "rocking" seats have met the same fate as my Z, ie, customer (in this case prev owner) goes to mechanic and says the seats are sliding around; the mechanic, not a Z mechanic and knowing nothing about bushings etc, assumes that means that the seat (mounting) bolts are lose, and wanks on them... to the point of torquing the heads off them [actually in two stages: customer tells mechanic that the seats are lose, mechanic "tightens" the bolts, or finds them already tight, gives the car back to the customer saying he fixed them, the customer comes back and says the seats are still lose, so the mechanic really "tightens" the bolts, torquing off the head of one or more]. That's the only way I can imagine the head got torqued off one of the bolts on the driver's seat. [and actually, the rocking and sliding, was one of the reasons that the PO sold the Z - the mechanic after "tightening" the seat bolts, told her that the only answer was a new set of seats, ka-ching, $2000... at that point she gave up and I bought it for a song.] The other four Z owners in town that I'm friendly with - not a one knew anything about seat bushings, but very much knew about the sliding; and likewise sadly, didn't know about the popping welds of the trunk floor. My impression is that there a those (few) mechanics that know/understand Z's, and then there are the rest.
    Good point. Can you confirm that there are only 2 bolts (the 2 rear bolts illustrated above) to be tightened? Or is there another pair in the front side of the seat? I ask because I'm going to try to raise the seat as high as it goes and attempt to tighten them without removing the seat from the car. It seems like this should be possible.

  10. #10
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    I would recommend some Loctite on those bolts, if possible.
    Not sure that I would use red; blue might be preferable.

  11. #11
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    Fantastic gmushial! Great picture that will probably help solve my rocking issue. I'm putting in a set of Whalens over Christmas and will tighten the bolts down while I'm at it. Maybe even a dab of Loc Tite

    The penny fix I've seen involved using a penny or dime and literally jamming it in the gap on the front of the seat between the cushion and the rail. That probably can be bypassed by simply tightening the bolts. Can't wait to try it.
    Cooper
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  12. #12
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    Quote Originally Posted by wcampbelliv View Post
    Am I the only one confused by the terminology? I feel like people use sliding and rocking interchangably here.
    I had what I would call sliding. Occasionally the seat would move forward & clunk when braking. The Whalen seat bushings cured that. The stock bushings had more or less turned to goo when I pulled the seats & inspected them.

  13. #13
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    Quote Originally Posted by MCoupeStud View Post
    Good point. Can you confirm that there are only 2 bolts (the 2 rear bolts illustrated above) to be tightened?
    Only two bolts on the rear. The front is held down by stamped in hooks on the slide rails. Over time those will wear slightly and the seat will squeak. That gap would need to be filed with something thin. I used some card paper.

  14. #14
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    Quote Originally Posted by steve f View Post
    Only two bolts on the rear. The front is held down by stamped in hooks on the slide rails. Over time those will wear slightly and the seat will squeak. That gap would need to be filed with something thin. I used some card paper.
    Thats where people have jammed a penny or a dime. I think a plastic or wooden shim would work best. That way you get the proper angle or support and can clip/break off the remaining portion of the shim.
    Cooper
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    '02 Topaz 3.0 (2009-2020)
    '97 Montreal 1.9 (2005-2009)

  15. #15
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    Bad news - tightening the bolts pictured above didn't solve anything for me. I just got back from doing it. Basically I was able to move the seat forward and raise it as high as I could, and I had easy access to the bolts. They were tight already but I gave them another push just to ensure there was no movement. I also verified the 2 nuts and 2 bolts that hold the seat in place to the floor of the car.

    Now I don't really know where to go from here. I verified that the bushings were good over the weekend, and I have ensured that the bolts that prevent rocking are tight. I think these seats just fall apart over time. The play is not bad, but it's enough to bother me if I'm paying attention.

    My driver seat moves a little strange. Instead of rocking evenly, it kinda rocks diagonally a bit...it's almost as if one side is more loose than the other.

  16. #16
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    my drivers seat does the same thing. I had the seat out twice now and cant figure out what the cause is. Very annoying . I serched for info on "the penny fix" with no success.

  17. #17
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    One thing to look for is how well the bolts line up for the seat rails. My passenger seat lines up perfectly while one of my rear bolt holes is not perfect, and requires some "handling" to get everything lined up. I can get the passenger seat out and back in really quick, but unless the bolts are really tightened down and manhandled into place, it will rock.

    Easy determination if this is it - see if you can hand-tighten the bolts with the rails in place. If that's not super easy, then your bolt holes aren't lined up. Hard to imagine, but...I have a second driver's seat rail, and it fits exactly the way the first one fits. Was thinking of going the racing seat route for a while.
    2018 X4 M40i

  18. #18
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    Quote Originally Posted by Telecomtodd View Post
    One thing to look for is how well the bolts line up for the seat rails. My passenger seat lines up perfectly while one of my rear bolt holes is not perfect, and requires some "handling" to get everything lined up. I can get the passenger seat out and back in really quick, but unless the bolts are really tightened down and manhandled into place, it will rock.

    Easy determination if this is it - see if you can hand-tighten the bolts with the rails in place. If that's not super easy, then your bolt holes aren't lined up. Hard to imagine, but...I have a second driver's seat rail, and it fits exactly the way the first one fits. Was thinking of going the racing seat route for a while.
    In this case your blocks on the screw drive (kabobs) may be slightly out of sink.

  19. #19
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    Quote Originally Posted by MCoupeStud View Post
    Bad news - tightening the bolts pictured above didn't solve anything for me. I just got back from doing it. Basically I was able to move the seat forward and raise it as high as I could, and I had easy access to the bolts. They were tight already but I gave them another push just to ensure there was no movement. I also verified the 2 nuts and 2 bolts that hold the seat in place to the floor of the car.

    Now I don't really know where to go from here. I verified that the bushings were good over the weekend, and I have ensured that the bolts that prevent rocking are tight. I think these seats just fall apart over time. The play is not bad, but it's enough to bother me if I'm paying attention.

    My driver seat moves a little strange. Instead of rocking evenly, it kinda rocks diagonally a bit...it's almost as if one side is more loose than the other.
    Quote Originally Posted by kieskaman View Post
    my drivers seat does the same thing. I had the seat out twice now and cant figure out what the cause is. Very annoying . I serched for info on "the penny fix" with no success.
    Mumble... Maybe it's just my New England blood [don't throw it out until it's truly used up or hopelessly broken]... but if they were my seats, I would go to the garage (mine looks more like a three-car woodshop/metalshop, than a place to park cars], grab a half-sheet of 3/4" junk ply, ie, something left over from a previous project, pop the offending seat(s) out of the Z's, and bolt it/them down to the ply (as if it were the Z's floor), and then rock them (while standing on the ply). The biggest part of the problem I had with seats in trying to figure out what was/wasn't happening, was access while they were in the car. But by having them out and bolted down, one can rock them, torque them, sit in them and stift them etc... and see what's happening. I know I couldn't sort out the rocks and rattles with them in the car, and likewise, out loose on the ground.. but by having them anchored, especially if I can stand on the edge of the ply and keep it stationary, I (strongly) suspect I/one could figure out where the motion is coming from.... just a thought.

    greg

    Quote Originally Posted by Telecomtodd View Post
    One thing to look for is how well the bolts line up for the seat rails. My passenger seat lines up perfectly while one of my rear bolt holes is not perfect, and requires some "handling" to get everything lined up. I can get the passenger seat out and back in really quick, but unless the bolts are really tightened down and manhandled into place, it will rock.

    Easy determination if this is it - see if you can hand-tighten the bolts with the rails in place. If that's not super easy, then your bolt holes aren't lined up. Hard to imagine, but...I have a second driver's seat rail, and it fits exactly the way the first one fits. Was thinking of going the racing seat route for a while.
    Actually easy to imagine... actually seems to happen about half the time I replace bushings.. but it actually makes sense - when one was using the oem rubber bushing, there was enough play/slop that even if the drive screws were slightly out of synch, one could still get the bolts and holes to mate... but as soon as one go to the poly bushings, and there's zero give: happens most of the time.

    I've now done bushing on three Z's around town (my own, plus two other peoples), and depending on how one proportions the thickness of the poly bushings, one will have to adjust the drive screws so that the bolt/holes center. So, actually I've gotten to the point that I don't bother with counting thread or measuring the sliders before putting the seat(s) back in... I simply get them close, put the seat in, and after pulling one of the drive "springs" (piece that goes from motor to right-angle gear), bolt down three of the bolts for the seat (snug, but not tight), and then using a cordless drill, drive the disconnected drive so that the seat becomes perfectly centered over the last hole/bolt. Then I connect up the motor again and everything is good to go.

    I learned this the hard way in that I had been super careful w/re positioning the sliders, only to have the fourth hole come nowhere near... but then thought about it... and what I had done different was: generally/before, I would shave the bushings (F/R) about the same until they could be crammed into the holders... but in this case, I had decided to put one of the bushings in full thickness, and only shave the other one until it would fit. Result of course being that the drive nut on one side was centered, and on the other was shifted off centered, screwing up the relationship btwn the sides. And actually on a different case where a stealer had dicked with the seat - it seemed that their fix was of intentionally skew the drives to take up the space from the missing/degraded rubber, so, even if one was super careful about keeping the relationship as it was when one pulled the seat out, there was zero chance that that was going to work/be correct after putting the poly bushings in.

    So: bottom line: put the seat in, tighten down the two rear bolts, and generally the console side of the seat front nut, and then adjust the slider on the outside of the seat until it mates (is perfectly centered) over the stud... put that nut/washers on, and then go back and torque everything down. A lot easier that way. And this is especially true if one is dealing with a seat with a dead drive motor.

    grg
    Last edited by gmushial; 12-25-2012 at 02:41 PM. Reason: Automerged Doublepost

  20. #20
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    rocking seats

    sounds like a plan...will try that after Christmas when all this rain stops coming down & wind stops blowing. Thanks for the tip. I hope it works for me. Merry Christmas.
    Last edited by MORRIE; 12-25-2012 at 01:42 PM.

  21. #21
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    Both of my seats are sliders so it looks like I've got a project on my hands.

  22. #22
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    Mine are both sliders, too, but I am going to wait until convenient to put in the glovebox and clutch pedal bushing kits while the seats are out.

  23. #23
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    clutch pedal bushings

    Hey, Vintage, wanna come to Birmingham,Al & help me with my squeaky clutch ....think it must be those bushings. I'll buy you dinner at J & N BBQ...yummy!!

  24. #24
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    Quote Originally Posted by Vintage42 View Post
    Mine are both sliders, too, but I am going to wait until convenient to put in the glovebox and clutch pedal bushing kits while the seats are out.
    While I have found the info on the seat bushings, I haven't found out where these fixes are in the FAQ yet. Any tips?

  25. #25
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    my "slight rocking" is more up and down than back and forth.

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