Trying to track down parts for some spring projects and was hoping somebody could help confirm what isolators the 6.2 diesels used inside the clam shell motor mounts? Mine is an '84 K5 and I'm looking to go with Energy Suspension poly mounts but they don't list the squarebody 6.2's on their site and looking elsewhere I'm seeing people say they either used the same as a SBC (3.1116) or a 2wd BBC (3.1121) or a 6.5 out of GMT400 (3.1152). Anyone have any recommendations?
CK5
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6.2 Clam Shell Isolators?
- Thread starter NorCalAnthony
- Start date
I have not used poly motor mounts, but I have used rubber SBC motor mounts with a 6.2L in the past and they fit perfect. I'm guessing all of the above are possible solutions as the numbers are close enough to be interchangeable. The big block or 6.5L mounts may be better for the weight in the long run though.
I thought they were the same too.
Looked at LMC to try to do some more cross referencing. According to their online catalog, all of the '73-'91 small blocks and the 82-83 diesels use the same mounts (#34-0321) and the '84-'91 diesels use the same mounts as the '73-'91 2wd big blocks (#34-0330). Looking at the pics of the poly mounts, they all have the same general shape but the SBC are physically smaller/shorter and more narrow than the other ones. Here's a pic someone posted on another forum that was having the same problem. SBC isolators towards the top, BBC in the middle, and diesel mounts (listed as '88+) towards the bottom.
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I look at it this way: all the available factory engines had the same mounting interfaces at the frame and transmission. It shouldn't make a fitment difference at all, but maybe had *potentially* some more vibration isolation out of the factory for the diesel. That said, you're going to lose that vibe isolation with poly (vs. rubber).
The only I know from experience is 4wd vs 2wd, he 2wd is lower.
Looked at LMC to try to do some more cross referencing. According to their online catalog, all of the '73-'91 small blocks and the 82-83 diesels use the same mounts (#34-0321) and the '84-'91 diesels use the same mounts as the '73-'91 2wd big blocks (#34-0330). Looking at the pics of the poly mounts, they all have the same general shape but the SBC are physically smaller/shorter and more narrow than the other ones. Here's a pic someone posted on another forum that was having the same problem. SBC isolators towards the top, BBC in the middle, and diesel mounts (listed as '88+) towards the bottom.
View attachment 370626
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View attachment 370628
I will try and check on my 84 diesel and compare to my BBC if I can get in there measure
If you can great but if not don't worry about it. I'll probably hold off on ordering them until I get to that point so I can make sure they're the right ones while I'm still under a return/exchange policy lol. I just like to plan ahead and have stuff like that ready to go before I start a project to minimize down time.
I used the SBC ones on my '84 (with an '82 engine block). I found that the '84 clamshell used a different bolt pattern on the frame side compared to my '86. 
At the end of the day, you will be fine so long as your clamshell matches the shape of your insert. See which style you have and order an insert to match.
At the end of the day, you will be fine so long as your clamshell matches the shape of your insert. See which style you have and order an insert to match.
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