chargedvx6

I have a built auto in the car and it was also run in my last car too. The thing is when I'm applying the brakes and the trans shifts down to 1st there is a sharp "pop" sound from the region of the brake booster or trans dipstick tube.

It can't be replicated when the car is stationary so I can't really suss it. The trans shop say it's nothing to do with the trans but that is the only thing common between the 2 cars so it has to be the trans. What in the build could be causing it?

daniel6718

iTrader: (36)

transmission mount is broken....replace with a polyurithane one

TireSm0ke

iTrader: (1)

I would only go with a poly trans mount if you have poly motor mounts, because if you launch the hell out of it thats how you break ****. And I would only go with poly mounts if I was making enough power, the stock rubber mounts are fine for most people.

chargedvx6

The mount is new with the trans which only has a few thou on it. I checked everything external and it seems to be good.

TireSm0ke

iTrader: (1)

Sounds like driveshaft u-joints, but you said its coming from the front of the car. Check for vacuum leaks coming out of the brake booster, other than that I cant think of anything from the front that would make a popping noise.

chargedvx6

Something occured to me today. When the car is at a standstill on a hill (like at a red light) if I leave my foot off the brake the trans/ converter takes up the slack to hold the car there but if I apply the brake the converter loosenes up and lets go completely.

Makes me think that the trans and brake booster share a vacuum circuit somewhere that may be causing the pop noise I get. Any one got some ideas because I can't suss it and if brakes are involed it is a concern to take care of. Definately sounds like the trans dipstick purging air or something in the booster when coming to a slow with the brake applied dropping back to 1st.

Any ideas peoples because I'm fresh out?