I had the truck parked for 10 days while we were on vacation. After returning home I needed to move it slightly, so I started it up and immediately placed it in Drive to nudge it forward. Truck just sat there. I put it back in Park, then back into Drive. Still nothing. Reverse seemed to catch, then back to Drive and it was fine and has been so ever since. Afterwards, I was wondering if the TC had drained out for some reason after sitting there for so long and needed to fill up. Anybody else ever seen this? Only a 10K before the drivetrain warranty goes, so I'd like to get any problems fixed while I can.

 

The fluid sometimes drains back. You need to let it idle in neutral for a short while to prime things up.

 

I've read in some instructions that after storage it's necessary to idle the truck in neutral for at least 30 seconds to fill the TC before applying any gear. (Drainback)

Sounds pretty normal to me

AlpineRAM

 

Maybe someone can educate me. I've read several posts concerning using neutral and one that even said the trans WON'T pump in park. I don't understand this as it's conrtrary to every other automatic trans I've ever dealt with. Does the torque converter not drive the pump on this trans? Willing to learn.......

 

As I understand it, your statement is correct. You must be out of Park for the pump to operate. In the winter when it's really cold up here, I leave it in Neutral for a minute or two for the fluid to get busy or it hesitates and complains a little.

So I guess that when I shifted out of Park, it must have taken 10 seconds or so for the pump to fill the TC to a point where I had enough coupling to make the truck ease backwards a little.

 

All Chrysler rear wheel drive trans have been that way since 1965 when the alumimum case came out. There is a check valve that can get leakey and then it will do it most of the time.

 

So the converter doesn't drive the pump, or the pump doesn't work in park, or both? Or maybe the checkvalve doesn't allow pumping in park? Maybe I should've prefaced this by saying I've rebuilt transmissions(not Chryslers) and I'm kinda interested in the how and why a trans wouldn't pump fluid in park with the engine running. It seems it would be terrible for any bushings or bearings that are part of the rotating assembly in park.

 

The valve body cuts off flow to the converter in park. The rest of the trans gets fluid. Not sure why it is set up that way, but always has been. I have a Ram van in the yard that has a defective check valve, bought it that way in 1992, put near 100,000 on it. I just start it in neutral.

 

Yup, TC drainback.

Had my truck parked for a week while working graveyards and taking the motorcycle to work.

Started it up today to come to work (raining kitties and puppies so no bike today) and it did that same thing,
just sat there for about 10-15 seconds, then slowly started creeping forward,
popped it into neutral for 10 seconds, then back to drive and it worked just fine.


phox

 

Thanks for the explanation!

 

If you have worked on transmissions, you can easily change the valve body to pump in park. You just need to drill a hole, I believe. The shift kits all pump in park.

 

My truck sits in my shop most of the time & only comes out to pull my 5vr. It will sit there sometimes for a month before I drive it. I always start it up & shift into N & let warm up for 5 min. before putting in drive & pulling out of the shop. Also shift into N first before going into reverse or park, makes for a happier transmission.

 

Signature shows you have a DTT tranny.

In DTT trannys, the check ball has been removed to allow better flow at their higher fluid pressures. Repeatedly not allowing 30+ seconds at idle, after overnight (or longer) can cause severe wear on the accumulator piston.

On a DTT Tranny, Neutral is better for cooling flow...same as stock.

I'm no tranny expert...but these were two of the things I had stressed to me, by my installer, when I asked for a list of any Do's & Don't !

RJ

 

I wish.... It's a DTT exhaust. But it's good to know that facts you stated above.

 

Got you...thought you just left off a coma! My mistake.