Sometimes when I start my car it lurches forward like I was shifting from "P" to "D", but all I'm doing is turning the key and starting the engine.

I have about 4,000 miles on the odometer. It doesn't seem normal and it happens occasionally, so I don't know if it'* a trait of the heavy duty transmission or the beginning signs that something bad is about to go down.

get a trans shop to check it out. or the dealer.

That is "normal" trait of the transmission. It only happens occasionally because the trans has to be in a specific position when you shut the car off the previous time.

Mine does the opposite. When I go from D to P, it lurches forward after I take my foot off the brake. Usually that just means that all the gears and such have to line up and sync with eachother.

:?:

the gears in an automatic tranny are always in contact with each other, not sure why they'd have to line up and sync?

Maybe my explanation is wrong, but that is what it feels like. It does it in any car I've been in.

i disagree. it'* not a normal trait of the tranny. that should not be happening at all.

and i have no idea what you mean by 'the trans has to be in a specific position when you shut the car off the previous time'.

huh? the only thing that lines up when you park your car is the parking pawl. once that'* engaged, there'* nothing *to* line up. if it is happeneing, said person has clutch packs that are sticking, instead of staying in 'park'. on this trans, the lower band should be applied, the 1-2 shift solenoid is on, and all other clutches are disengaged.

if your car is lurching when you turn it on, take it back to the dealer. end of story. it should *not* do that under any circumstances.

prolly what you're feeling is the engaging/disengaging of clutches.

here'* something to try. find yourself a nice big hill, and park on it. put the tranny in park, and don't set the parking brake. see if you stand still. it could be that your parking pawl is not engaging, which might (but still shouldn't) allow some power to get transmitted to the wheels.

again, unlikely. take it in to the dealer. i'm assuming you're talking about a gxp by your member name, it should still be under warranty, correct?

Yes, it'* a GXP.

Off to the dealer I go. Thanks for everyone'* responses.