How do you know if your body mount bushings are bad?

[The motor guy]

I noticed the rear of my cab is rubbing the fuel tank on my older 99 dodge cummins 2500. Looks like the very top of the tank in that one spot is slanted slightly and one side rubs. Are cab mounts supposed to bulge at all? Other than some slight weather cracking and slightly bulging on the sides, I don't see an issue

 

[Timmastertech]

Pictures?

 

[The motor guy]

Pictures?

I'll take some

 

[The motor guy]

Here's some. Other than being a tad bulged out, they seem fine.

 

[The motor guy]

That L bracket are my side steps. Apparently I bought the cheap kind that utilize the body mounts, but I don't think that has anything to do with the problem.

 

[The motor guy]

I take it they're okay? Or would a fresh set give me an extra 1/4" of height I need so it's not rubbing the tank?

 

[The motor guy]

I'm just going to loosen the tank and slide a couple tool drawer liners in between the tank and cab and call it good for now I guess. A permanent solution would be to drop the tank grind some metal away to make some clearance.

 

[The motor guy]

I don't get why people ask for pics then have no input