slight vibration when stopped in traffic

[aussieghostrider]

I just had my balancer replaced about 3-4 weeks ago with a genuine new one as engine was making a rattle anyhow which cost me a bit & this is the 3rd one since 1990 , anyhow ive noticed last few days there is a slight Vibration when Im in drive and my foots on the brake like when your in traffic.

Sometimes it does it and sometimes not , it's almost like its sort of misfiring but when I put car in N or P it goes away and idles great and no vibratiion & when in D and foots off brake and rolling along & or I acclerate no noises.

The car goes hard and revs out no problem as I have taken care of the car since my parents bought it in 1990 from the dealer brand new.

Ive ran a bottle of nulon petrol total system clean as I always do every 3-4months and its sort of helped but not really.

Also last say 6 to 12 months when car has not been driven can take few seconds to go into Reverse or drive but I expect it casues it cold as doesnt do in summer but mechanic I spoke to said it could be torque converter which he said is like $900 to replace and he doesnt do it but knows of someone.

with my Balancer being brand new then it couldnt be that could it ?

any ideas people as if its the balancer I will have to take back to the guy who fixed it few weeks ago.

[sebstenator]

could be an oil pressure problem?
check the pickup that its not clogged or your oil pump.