car shakes when at red light is stall an issue?

[freaky57fast]

I have noticed it this year only when I'm at a stop my car shakes a bit. I'm not 100% sure but I think its to do with my stall being stock I shift up to neutral and alls good but I'm just concerned that the trans is acting up. I have LTS y pipe and lm1 cats back with 275 40 r17 on the back it knocks me 2.4 Or so mph so I'm just thinking its the stall any opinions on the matter?

[pajeff02]

Check your transmission mount.

[freaky57fast]

Will do I need it lifted soon anyways I just figured stall cause when I get off the brake it wants to jump then coast.

[pajeff02]

What rpm is your car idling at?

[freaky57fast]

No more than 1000rpm that's why I'm confused I think it might be account for my exhaust having leaks? Idk

[pajeff02]

Idle should be around 550 or so.

[freaky57fast]

Yeah depending on temp like 6 maybe but I just looked under it found a loose clamp.... right under my feet so next step is a weld and maybe my shoes won't rattle if not then I'll lift it and check the trans Mount like you said. Hope its one or the other.