engine mounts....

[LOGANSTANFORTH]

i thought all chevy engine mounts were the same, 250 6 cylinder all the way up to 502 and then some.......when i pulled the engine out of the 79 c20 truck to put in my blazer, we got it all in and on one side the bolt holes wouldnt line up when we went to drop the clam shells down onto the rubber mounts, i had to lift the engine and swap out the clam shell with the one from the original blazer engine.....

 

[Russell]

I've run into that a few times as well. I always just keep the clam shells with the particular truck now. The engine mount towers and the rubber isolators are all the same though.

 

[80' 427]

I pulled a 78 454 put it in a 73 K20 then pulled it out and put it in a 79 k30 all the mounts were the same.

 

[73k5blazer]

There's some sublte differences over the years.

For instance, those with early 1973 trucks, have to put spacers under the mounts because GM started producing them for whatever reason with a slightly lower mount pad, and the parts books show a change in the part number for the mounts mid-way thru 1973 production.
How do I know that you might ask? I replaced the mounts in my 1973 k5 back in the mid 90's with standard ones from a parts store, the same listed for all 73-87/91 trucks, and my balancer was rubbing slightly on the frame crossmember. After exhaustive reasearch, I found mounts for those early trucks simply don't exist, leaving one with the only option of putting a spacer plate under the mounts.

 

[toomany]

In theroy they are all the same. But there are some slight differances as stated above. I've run into clamshell problems when swapping a motor from a truck into a car (straight drop in). The motor was tilted to one side...drivers IIRC. Also some will have a captured nut on the pass side so the fuel pump won't need to be removed.

 

[desertrat67]

Original bigblcok trucks were a bit different also. this from ORD concerning their mounts:

These are a bolt-in replacement for the factory small block or diesel mounts. They will not fit an original big-block truck, the frame bolt pattern is a little different. The DO fit small block trucks that are swapping in a big block motor. An example is our green K5, it was originally a diesel, then ran a 383 small block and then we bolted the 468 big block into the same mounts. Our mounts will not bolt into the 1-ton truck that the came in from the factory.
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