2002 QX4 - slight movement after put in park

[funnyman82]

Hello all,

This has happened to me a couple of times while waiting in line at a car wash: I move forward and then put it in park while i am waiting for the line to move again. After putting it in park about 10-15sec later i feel it try to move forward a bit. Do you know why this happens?

Thank you!

[SOUTHSHOREQX4]

I get the same thing when i park in my driveway...I think it has something to do with when you change from 2wd to Auto, at least that's when it happens to me. For example. I started my car the other day and it was in 2WD Hi, there was a light coating of snow so before I started driving I switched to Auto. When I got to Lowe's I parked and after turning the key off it did a little roll forward. If I'd left it running about 15-20 sec. while running it would do the same roll. I've had this happen since i owed the truck. I don't think its anything to worry about. I think its the 4WD disengaging when the computer senses there's no need for it when your standing still.

[funnyman82]

Thx for your reply. It's not that the truck actually rolls but you feel a slight movement forward almost as if there was a gust of wind...at least someone is experiencing this other than me..

[SOUTHSHOREQX4]

I mean it doesn't actually roll down the road, but like you said a slight movement. When it first happened to me I thought oh well there goes the transmission linkage, but not the case at all. Like I said, it always happens to me and so far so good no problems with the transmission at all.

[Densetsu]

I've had the same issue with my '03 and '04... both of them would lurch ahead a tiny bit in lineups like that. The first few times it did it, I thought the guy behind me tapped my bumper as he was pulling up in line. I also notice every morning/evening (or whenever the Pathy has been parked for a few hours), when I start it up and take it out of park it also has a similar feel. In both cases, I've just come to the assumption that it's the transfer case.

I've been in Auto and 4Hi since November, so I can't remember if this has happened when I'm in 2Lo... I should give it a try and see if it still happens.

[Towncivilian]

Never had this issue with my 2WD. I also engage the parking brake before shifting into Park.

[ARKQX33V6]

Change the transmission fluid! Change every other year and this will stop. I've discovered that the solenoids get dirty with contamination and are held off center just enough to cause the feeling that you describe, it drove me nuts figuring this out, but a simple fluid change keeps the contaminants to a low enough state that the solenoids operate as they should.

No actual movement in the car unless the valves operated by the solenoids are way off. But if just enough to cause fluid leak enough hydraulic pressure to get that run down and stopping sensation

[Densetsu]

I checked the fluid on this Pathy when I bought it (of course) in the summer, and checked it again this fall when I started driving it. Both times the fluid on the dipstick looked the usual bright red, and there was no sign of debris.

I'll be changing it in the spring when it warms up; hopefully it'll go away. It'd actually be kind of scary if that was the source of the problem, though, because that means I've been going all winter with dirty transmission fluid.

[ARKQX33V6]

Debris won't show on the dipstick but will cause valves to lag and hang up, when you change oil flush a few quarts through retain all you dump in a container, let sit for a day then look and feel the oil at the bottom. It is surprising, wear and tear is normal for friction materials and that transmission has lots. Recommendation is 40,000 or 2 years. I change it every other year, like all lubricants...pumpkins, brake fluid, power steering, transfer case, anti freeze and of course every 6 months on oil. Just engine oil is 100% synthetic, the rest isn't in long enough.

[carnal_c30]

you should be using the parking brake if you are doing that,

http://auto.howstuffworks.com/auto-part ... /printable

Technically, yes. In the Park position, the output shaft of the automatic transmission is locked in place by means of a pin inside the transmission. In other words, in 'Park' the transmission is locked up and the wheels can't turn. This is why people can get away with not engaging the parking brake. But the pin is relatively tiny and the transmission and output shaft are massive, and relying on this pin (called the prawl) places the entire transmission mechanism under stress. In park, a car can gently be rocked forward and back, evidencing the placement of stress and torsion on the transmission.

The parking brake (it is not typically called the emergency brake, at least not on european auto-transmission cars) engages a drum brake that while not nearly as strong as the disc brakes that you use while driving, are enough to keep the car immobilized.

Proper stopping procedure:

Stop, with foot on brake.
Emergency (or parking) brake.
Put transmission in 'park'.
Take foot of regular brake. - Car should not move.

Proper start:

Ignition.
Foot on brake.
Release parking brake.
Put car in drive.

[Towncivilian]

I do the following when parking:

• Come to a complete stop
• Shift into neutral
• Engage parking brake
• Let foot off of brake, wait for car to stop its slight movement
• Shift into park

This way, the vehicle never moves after going into Park, and shifting into Reverse (or Drive) from Park is significantly easier/smoother (no resistance on the shifter felt anymore). Also saves wear on that tiny parking pawl in the transmission as said above.

I also shift into the desired gear before releasing the parking brake when I want to move.

[yeldogt]

What you are feeling is the release of the tension in the 4wd system. You can get this when the electric transfer case releases or when you stop the car and shut the engine off in 4wd hi.

The trucks are not AWD -- everything is locked together - when it is in 4wd and the only thing that can slip is the tires. You will especially notice this if you are turning in 4wd Hi and stop the truck on dry pavement. This will also happen as you are driving in "Auto" as the system moves into and out of 4wd. Its not the the transmission doing this. Tires with different tread depth will add to this problem. I noticed this on my test drive when the truck was new.