issues with -webkit-transform in chrome on mac - macos

Question

I have a page with simple transitions. I am sliding in a panel from the left (class copyDeck) and I have an element that contains an animated gif (class animatedTank) that overlays a background image. I am adding a class of loaded to the body with js onload to fire the animation.
This all works great in all browsers, a user pointed out that on a Mac with the latest version of chrome we have an issue.
The div that I slide in is actually scaling in and the animated gifs containing element slides up from the bottom (I have no animations set for this element or its parents)
h1, .copyDeck, h1 + span, div.mainContent ul{
-webkit-transform:translateX(-60%);
-moz-transform:translateX(-60%);
-o-transform:translateX(-60%);
transform:translateX(-60%);
-webkit-transition: all .5s ease-in;
-moz-transition: all .5s ease-in;
-o-transition: all .5s ease-in;
transition: all .5s ease-in;
}
.copyDeck{
-webkit-transition-delay:.125s;
-moz-transition-delay:.125s;
-o-transition-delay:.125s;
transition-delay:.125s;
-ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
filter: alpha(opacity=0);
-moz-opacity: 0;
opacity:0;
margin-top: 3em;
}
.loaded h1, .loaded .copyDeck, .loaded h1 + span, .loaded div.mainContent ul, .loaded blockquote, .loaded .CTA{
-webkit-transform: translateX(0);
-moz-transform: translateX(0);
-o-transform: translateX(0);
transform: translateX(0);
-ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
filter: alpha(opacity=100);
-moz-opacity: 1;
opacity:1;
}
.animatedTank {
background: transparent url("Assets/transportation_imgSeq.gif") top left no-repeat;
width: 212px;
height: 369px;
position: relative;
top: -340px;
left: 389px;
float: left;
}
<div class="mainContent">
<div class="fadeOvr"></div>
<h1>Level Tanks</h1>
<span>& A Better Bottom Line</span>
<div class="copyDeck">
<p>
...
<ul>
<li>...</li>
<li>...</li>
<li>...</li>
<li>...</li>
</ul>
</div>
</div>
<div class="animatedTank"></div>
Does anyone know of a fix, solution or has anyone experienced this issue?