Why is my car rolling forward in Neutral?

[acarmody]

So Auto VX V6, and when it is neutral with no handbrake or brakes it will slowly roll forward. Not as fast as if it was in drive, just slowly. Doesn't take much of an angle to stop it either. It even does it when the last gear was reverse.

[304runner]

Gravity.... Its a bitch of a thing.....

[BlackVXGTS]

Item 29 of 4L60e common problems and failures may help:

Car acts like it's in OD in neutral, car is locked stationary in R, engine feels loaded in P, all four forward positions work fine:Internal crossleak feeding the forward clutches all the time. Most likely a cracked input housing. R&R required. Car can safely be driven gently in forward gears until the repair.

[Cameron P]

Please ignore.

i think he means it does what drive would do and roll forward but on a smaller scale... correct arcarmody?

[acarmody]

i think he means it does what drive would do and roll forward but on a smaller scale... correct arcarmody?

Correct.

Its like drive but without as much speed or torque.

Gravity.... Its a bitch of a thing.....

Zapp voice "YOU WIN AGAIN GRAVITY'

Nah seriously I know my garage is flat.

[Cameron P]

maybe an issue with the torque convertor? not to familar with auto's lol

[VTSSDUDE]

If you car is an automatic, if motor is not running. Neutral, Reverse, or in any forward drive gears it will act like it is in neutral and free roll.
Only when hand brake (if working) is on or in Park (gearbox is in good working order) then the car will only then be stopped from rolling freely.
Automatic boxes don't have a direct connection to the engine, they go through a torque convertor and only under centrifugal force is then the gearbox is able to drive the back wheels accordingly to the engine.

[Cameron P]

lol i dont think he is talking about when the car is off either!!

[VTSSDUDE]

Sorry I didn't read it thoroughly enough.
What revs does your car sit on in idle? It could be sitting too high. As in neutral if you rev the car it will move forward gradually.

[Munz]

geez arc I really thought you were takin the piss on this one



imo that shit should sit still in neutral
But i have no idea....so this post is useless

[BlackVXGTS]

What revs does your car sit on in idle? It could be sitting too high. As in neutral if you rev the car it will move forward gradually.

Completely untrue. In neutral the car will not move at all (except for acarmody's car).

[acarmody]

@ Munz, I take the piss on a lot of thing, but when my car is parked within 20cm of the wall, and I turn my car on and it start rolling forward, I like to talk serious. On a positive note I have really fast reflexes, I got the handbrake on real fast, which isn't bad considering I was outside my car when I turned it on,

@VTSSDude, she idles at the correct RPM, about 700 or so.

@BlackVXGTS, LOL.

An issue with the torque converter would at least give me a reason to buy a new one that will make full use of my cam but I can't see that being the problem. I always thought in neutral the gearbox internals are all spinning but none of the gears are engaged to spin the output shaft, but in park the gearbox is locked and the torque converter takes all the punishment. Wrong?

[oska]

what does your IT DAD think ?

i would have thought, he would have the answer

[VK SL 3800]

My initial thought was exactly what the second posts says, but having drive in neutral is pretty strange, i cannot think of any explanation unless a clutch pack isnt fully disengaging or something like that. You might just have to be wary of it and see if the problem develops further as the worse it get the easy it will be to diagnose for the mechanics.

[GEN3RATD]

have you tried revving it and dumping it in drive, should fix it

[acarmody]

what does your IT DAD think ?

i would have thought, he would have the answer

I don't know what he thinks, but I think you should stop trolling and get over yourself.

[VTSSDUDE]

My VT SS when I first start it and it's in park it rolls forward about 5mm, and if in neutral if I rev it hard enough if will move forward slightly if on flat ground.
All autos will do this, jack the back of your car up with both wheels off the ground, start the car put it in neutral and I can gurantee you your back wheels will be spinning.
So @Acarmody's "issue" is explainable just dont' know why at idle (700rpm) it's moving forward. As someone said above may there is too much pressure on the clutch pads, whether or not there is an adjustment issue, the gear selector might be still in drive a fraction, a faulty solenoid.
Get a gearbox place to check it out, hope it's not something serious.

[VTSSDUDE]

Item 29 of 4L60e common problems and failures may help:

Car acts like it's in OD in neutral, car is locked stationary in R, engine feels loaded in P, all four forward positions work fine:Internal crossleak feeding the forward clutches all the time. Most likely a cracked input housing. R&R required. Car can safely be driven gently in forward gears until the repair.

I must had been reading this thread with eyes shut yesterday, I didn't see this reply.
This would make sense. Let's hope it's not a cracked input housing.

[Cameron P]

what does your IT DAD think ?

i would have thought, he would have the answer

not cool bro...

[pablo]

Just on a safety angle, it is a bad practice to start an automatic while it's trans isn't in 'park'. Or a manual if the foot or handbrake isn't applied. This particularly applies in the case of the engine being started while the driver is outside the vehicle.

I once had my V8 auto take off at speed down the drive way, only to end up going through the old mans closed garage doors!....LOL...................tho I wasn't laughing at the time, particularly when the Dad came home!

[Cameron P]

Just on a safety angle, it is a bad practice to start an automatic while it's trans isn't in 'park'. Or a manual if the foot or handbrake isn't applied. This particularly applies in the case of the engine being started while the driver is outside the vehicle.

I once had my V8 auto take off at speed down the drive way, only to end up going through the old mans closed garage doors!....LOL...................tho I wasn't laughing at the time, particularly when the Dad came home!

yeah mate cause he said he starts it in neutral or drive lol

[DLFHUB666]

[QUOTE=acarmody;1914742]@ Munz, I take the piss on a lot of thing, but when my car is parked within 20cm of the wall, and I turn my car on and it start rolling forward, I like to talk serious. On a positive note I have really fast reflexes, I got the handbrake on real fast, which isn't bad considering I was outside my car when I turned it on,

Well by that statement there reading between the lines sounds like he does start his car in other gears than park.

[Cameron P]

[QUOTE=DLFHUB666;1915449]

@ Munz, I take the piss on a lot of thing, but when my car is parked within 20cm of the wall, and I turn my car on and it start rolling forward, I like to talk serious. On a positive note I have really fast reflexes, I got the handbrake on real fast, which isn't bad considering I was outside my car when I turned it on,

Well by that statement there reading between the lines sounds like he does start his car in other gears than park.

could have started it in park then put it into neutral or something lol. i mean he never said he did

[DLFHUB666]

Well if he starts his car on the outside then starts changing gears while outside
He deservers to have his car lunch through the wall, that is just dumb.

[TrikkBen]

Is the box modified in any way, line pressure, shift kit??

This behaviour is present in most auto boxes, just at a much lesser extent in standard gearboxes. The problem is caused by residual line pressure still flowing through the valve body trying to turn the planetarys.
The reason I ask is once you start adding clutch plates and closing up the clearances to make them tighter this starts to happen.