lassy

I have noticed that when I start up my 91 W350 4x4, I can shift the transmission (automatic) from P to R to N to D etc and back to P and back to D without it ever "lunging" like it's ready to start moving in any selection. If I give it 10 seconds or so, and I make my gear selection, it will move and act fine, but I'm just curious if that's a common thing or is that telling me something needs attention? I spoke with someone at quad4x4 and he said the transmission has to build up oil pressure before it's able to operate properly.

Do you guys have any knowledge on this?

Thanks!

taterfarm

this is probably normal, if I understand it correctly the torque converter drains back while the truck is off. with the truck is running in park there is no oil supplied to the torque converter, so nothing happens until you shift to a gear or neutral to fill the converter. If you let the truck warm up in neutral then the fluid will circulate and it will go as soon as you shift into gear.

Or according to the directions in the transgo shift kit if you install the newer design manual valve it will allow the fluid to go to the converter in park, I would think that would eliminate the problem as well.

lassy

Thanks Taterfarm!

TIMMY22

aka morning sickness

Chrisreyn

Glad to see I am not the only one with this issue..
Mine didnt do this till I had the tranny rebuilt, now its an every morning thing.

TIMMY22

2nd gen tranny lines had check valves to help prevent this

2mtrucks

Very common. Every Dodge diesel I have owned did this. On really cold mornings I always put an auto in neutral for 10-15 seconds or so before driving away. Both my current trucks are manuals and they dont like the cold any better.

MARF75

When I start mine in the morning I set the ebrake and put it in neutral. Then the trans warms up with the engine

crazzywolfie

but from what i have read hanging around 2nd gen section those check valves can cause the transmissions to fail when they start to clog up which is why most people cut them out. i have also read of some transmission shops not warrantying there trans unless the check valve was remove. if only the transmissions would pump fluid in park we would not have this problem. i put my truck in neutral before i fire it up just so i don't burn up the transmission.