Differential "skid" plate? - NCRS Discussion Boards

Differential "skid" plate?

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Kenn S.
    Very Frequent User
    • September 10, 2009
    • 173

    Differential "skid" plate?

    Sometimes a part comes off a car that you have no idea what it's called. Not often, but sometimes. So I'm hoping someone out there knows what this part is called, perhaps a part number, and where one might find it if it's available. (I'd snap a photo, but foolishly I tossed it due to it's condition...I should know better.) Also forgive the lack of paragraphs...apparently the online editor isn't accepting an "enter" key press. In any case, I'm referring to a pressed-on steel plate that was installed underneath the aluminum differential carrier. It was pressed onto a pair of 3/8" (or so) bosses, and seemed to act like a skid plate (which is what I'd call it if the car was a 4X4). Mine was torn, bent, and covered with goo so thick I couldn't even scrape it off well enough to get a better look at it. Both my struts are bent, so I can only imagine what this plate must've suffered (I don't believe the struts should be bent...no pics I can find show new struts in that condition). If I don't find one, it isn't the end of the world, and I'll probably always kick myself for tossing it...I could have had one fabricated. Doh!
    -Kenn
    1970 LS-5
    1970 350/300
    1980 L-48
    2004 LS-1
  • Kenn S.
    Very Frequent User
    • September 10, 2009
    • 173

    #2
    Re: Differential "skid" plate?

    Sorry...forgot to mention. The AIM doesn't show it, and the parts book doesn't clearly indicate it either (obvious things like "Plate, Differential"). A quick look through Corvette Central and Corvette World don't show it either...
    -Kenn
    1970 LS-5
    1970 350/300
    1980 L-48
    2004 LS-1

    Comment

    • Joe L.
      Beyond Control Poster
      • February 1, 1988
      • 43221

      #3
      Re: Differential "skid" plate?

      Originally posted by Kenn Scribner (50830)
      Sorry...forgot to mention. The AIM doesn't show it, and the parts book doesn't clearly indicate it either (obvious things like "Plate, Differential"). A quick look through Corvette Central and Corvette World don't show it either...

      Kenn------


      The part to which you refer is an exhaust system HEAT SHIELD. It was GM #475340 and it was uniquely applicable to 1980 Corvettes. It was discontinued without supercession in November, 1988 and I don't know if it's reproduced or not. I would kind of doubt it, but you never know. Otherwise, a used Corvette parts source is going to be your best bet. Problem: most of the used examples out there are going to suffer from the same problems yours suffered from.
      In Appreciation of John Hinckley

      Comment

      • Kenn S.
        Very Frequent User
        • September 10, 2009
        • 173

        #4
        Re: Differential "skid" plate?

        Oh, now I'm really sorry I pitched it without tracing it. Bugger. Thanks, Joe. I somewhat recall approximately what it looked like, so maybe I can reproduce it myself, if I even really need it (planned on modifying the exhaust as it was)... Goes to show...throw nothing away until you're done...
        -Kenn
        1970 LS-5
        1970 350/300
        1980 L-48
        2004 LS-1

        Comment

        • Chris D.
          Very Frequent User
          • November 1, 2002
          • 198

          #5
          Re: Differential "skid" plate?

          Kenn, For the aluminum rear ends, the strut rods are angled with respect to the end bushings. If that is what you are considering as "bent" you may not be in as bad shape as you think.

          Comment

          • David H.
            Extremely Frequent Poster
            • June 30, 2001
            • 1530

            #6
            Re: Differential "skid" plate?

            Kenn,
            The shafts of the strut rods are straight on my 1980. Sometimes a shop would bend the rod shaft as a way to align the rear end (not a good thing). If the shafts are bent, I would replace them.

            As to the heat shield, I am away from my car for a few weeks, but I'll trace the shield out for you, if you still need it, when I get back.
            Judging Chairman Mid-Way USA (Kansas) Chapter

            Comment

            • Kenn S.
              Very Frequent User
              • September 10, 2009
              • 173

              #7
              Re: Differential "skid" plate?

              (Sorry..."enter" key still not working in this editor...) Chris: One is bent 7" from the end, the other 7.5" from the end. I'm thinking it's more like David says...someone heated them up and bent them (like you'd do for an old F-150). I'll replace them...not a problem there. Would replace the busings anyway. If another owner hit something badly enough to bend them, I'd think there would be damage underneath, and there isn't. When I removed the trailing arms, the bushings were pretty worn and the bolts rusted to the covers, so my guess is they took the lazy way out. David: Thanks! I'd love that...I'm sure I can fabricate one. It was essentially square with rounded corners, in the range of 11" or so, as I recall. Lesson learned, don't throw things away until you're done! (And maybe not even then...)
              -Kenn
              1970 LS-5
              1970 350/300
              1980 L-48
              2004 LS-1

              Comment

              • Joe L.
                Beyond Control Poster
                • February 1, 1988
                • 43221

                #8
                Re: Differential "skid" plate?

                Originally posted by Kenn Scribner (50830)
                (Sorry..."enter" key still not working in this editor...) Chris: One is bent 7" from the end, the other 7.5" from the end. I'm thinking it's more like David says...someone heated them up and bent them (like you'd do for an old F-150). I'll replace them...not a problem there. Would replace the busings anyway. If another owner hit something badly enough to bend them, I'd think there would be damage underneath, and there isn't. When I removed the trailing arms, the bushings were pretty worn and the bolts rusted to the covers, so my guess is they took the lazy way out. David: Thanks! I'd love that...I'm sure I can fabricate one. It was essentially square with rounded corners, in the range of 11" or so, as I recall. Lesson learned, don't throw things away until you're done! (And maybe not even then...)

                Kenn------


                The ends of the 80-82 strut rods are "offset" and not perpendicular to the rod itself. Some folks might interpret this as being bent, but it's the normal condition for these rods. However, the rod portion (i.e. between the ends) should be perfectly STRAIGHT. If this is bent, you need a new rod. The rods, GM #14010399, are GM-discontinued but available in reproduction.

                The usual way these rods customarily and historically get bent is some klutz service shop (INCLUDING Chevrolet dealers) bend the rods when they cannot get the rear wheel camber into spec. The right thing to do when this occurs is to replace the strut rod bushings but they either don't know that or they don't want to tell the customer about the extra expense. A VERY bogus practice but it's been going on for years and affects all 1963-82 Corvettes.
                In Appreciation of John Hinckley

                Comment

                • Terry M.
                  Beyond Control Poster
                  • September 30, 1980
                  • 15601

                  #9
                  Re: Differential "skid" plate?

                  Originally posted by Joe Lucia (12484)
                  Kenn------


                  The ends of the 80-82 strut rods are "offset" and not perpendicular to the rod itself. Some folks might interpret this as being bent, but it's the normal condition for these rods. However, the rod portion (i.e. between the ends) should be perfectly STRAIGHT. If this is bent, you need a new rod. The rods, GM #14010399, are GM-discontinued but available in reproduction.

                  The usual way these rods customarily and historically get bent is some klutz service shop (INCLUDING Chevrolet dealers) bend the rods when they cannot get the rear wheel camber into spec. The right thing to do when this occurs is to replace the strut rod bushings but they either don't know that or they don't want to tell the customer about the extra expense. A VERY bogus practice but it's been going on for years and affects all 1963-82 Corvettes.
                  Corvette rear strut rods also got bent when the car was improperly lifted on a certain type of lift. Back when most cars were Rear Wheel Drive (RWD) with live (solid) rear axles an in-ground two-post lift was in common use. The rear post had a U-shaped bracket that cradled the solid rear axle to lift it. While this worked well for the rear axle of C1s, this type of cradle contacted the rear strut rods of C-2 & C3 Corvettes and the weight of the car would bend the rods.

                  This type of lift has great clearance for exhaust and transmission work on RWD vehicles, but the preponderance of front wheel drive cars made this style of lift obsolete. Add the prevalence of hydraulic fluid leaks and few people other than us old farts have ever seen one of these lifts. I learned to wrench on one of these lifts, and even was able to use it on my 1970 -- but one has to be careful and know the hazards. Being a fan of RWD I mourn their passing in spite of their hazard to C2 & C3 Corvettes.
                  Terry

                  Comment

                  • Kenn S.
                    Very Frequent User
                    • September 10, 2009
                    • 173

                    #10
                    Re: Differential "skid" plate?

                    Guess I'm an old fart too, Terry. I do recall those lifts...didn't occur to me, but that makes the most sense. Bet it shocked the crap out of the service tech when he saw the car was hanging by the struts. I should snap a pic...the bending is just what I'd expect from improper lifting as you suggest. A little too precise for the old "heat it up and whack it" method, but that seemed the most logical until your suggestion. Some replacement struts are in my near future (sandblasting the frame now...planning to start painting this weekend).
                    To Joe...gotcha. No, these are markedly bent, about 7" from the shock mount. Great information, though...there are small but significant differences between C3 years, and I'll make sure to look for the right strut. That would be an easy mistake to make.
                    -Kenn
                    1970 LS-5
                    1970 350/300
                    1980 L-48
                    2004 LS-1

                    Comment

                    • Kenn S.
                      Very Frequent User
                      • September 10, 2009
                      • 173

                      #11
                      Re: Differential "skid" plate?

                      Bent. Luckily not too hard to replace. Not anywhere nearly as bad as the trailing arms I had to cut off. Those babies were trashed (and couldn't likely have been restored anyway...98% of the car isn't in terrible shape, but those, those were goners).
                      Attached Files
                      -Kenn
                      1970 LS-5
                      1970 350/300
                      1980 L-48
                      2004 LS-1

                      Comment

                      Working...
                      Searching...Please wait.
                      An unexpected error was returned: 'Your submission could not be processed because you have logged in since the previous page was loaded.

                      Please push the back button and reload the previous window.'
                      An unexpected error was returned: 'Your submission could not be processed because the token has expired.

                      Please push the back button and reload the previous window.'
                      An internal error has occurred and the module cannot be displayed.
                      There are no results that meet this criteria.
                      Search Result for "|||"