Engines falling out of cars

I saw a similar thread about modded engines falling like they have no engine mounts. The same happens to me with original engines in the game. Sometimes I can fix it on the specific vehicle by adding or removing parts, but then its not the car I want.
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It happens on all D series trucks, but the mod in the picture is the Ibishu Dove. I highly recommend this mod

 

Try clearing cache. If it doesnt work an upddate changed they way engine mounts worked so thats why

 

Do what @a plane guy said, and if it don't work you surely have an outdated mod, and the ibishu dove is outdated so it might be the reason the engine don't have mounts.