Engine mounts

[Exekiel69]

How do I know if I need to replace them? I have a set of new ones for some time thinking mine caused the cab to vibrate (sfw) but the new ones feel just the same as the ones I have on the truck now, this may be the ones that came from factory.
It doesn't look difficult to remove them (better not have the oil filter in the way) but it looks time consuming and I'm not sure they are bad since they look to be in one piece.

Thank You.

 

[RedTruck]

EZ,

Doesn't look like you've had many hits here so I'll take a stab at it. Mind you this is mostly speculation...so take it for what it's worth.

I don't think there is any concrete way (except for maybe obvious physical problems like chunks missing or excessive cracking) to look at your engine mounts and tell whether they are bad or good.

I've always gone by the rule of thumb that if you are changing engines change the rubber (poly is not available for our rigs) engine mounts. I believe that if they are kept clean they will last the life of the engine. If you have a fuel or oil leak that drips and accumulates on your engine mount I would believe that it could cause the rubber to deteriorate resulting in having to replace them.

I have not to my knowledge ever seen a thread posted stating that someones engine mounts went bad. On a front wheel drive car, when the engine mount goes bad, you hear a clunk when you accelerate from the engine twisting and causing the metal inside the motor mount to make contact. If the rubber failed on one of our rigs the engine is still secure. I'm just assuming you would hear some type of noise when the engine is put under load similar to a front wheel drive car.

 

[Agnem]

Having driven 2 vehicles with broken motor mounts (A 78' Dodge flatbed with a 440, and a Ford Tempo), I can tell you that you know they are bad when there is a big clunk either shifting, or changing directions. They generally are not responsible for vibrations being transmitted.

 

[Exekiel69]

The only vehicle I drove that had bad engine mounts was an acura and You can tell they are bad so I just thought a truck could feel different. I looked at them for a while and could not bring Myself to replace them since they looked almost the same as the new ones.

Thank You.