I've got an 08' GXP that is making a tapping/ticking noise coming from what sounds like the DOD lifter engagement. If I drop it into tapshift mode and put it in 3rd gear at low speeds it's extremely audible with the windows down. There is a little delay in the noise, probably 2-3 seconds before the DOD system engages once in 3rd. I noticed it driving through the downtown area where I live, I could hear the echo off of the buildings. It doesn't go away after any amount of time either.
The thing of it is, I just had all 16 lifters replaced in this car as well as a brand new transmission. The noise was there before the lifter replacement and it's still there now.
I took it back to Pontiac and they told me it's "normal" DOD noise and the car is functioning as it should. This makes no sense to me at all, there is no way they designed that DOD system to be audible. Second, of what I think I know about DOD it should not be engaging at low speed like that. Isn't there a minimal speed where it should engage? 45 ish? Even with it engaged it shouldn't be audible...
Any thoughts would be appreciated.
