91 A-518 Drain back, where is it located

Got a problem with a 91 dodge van with an A518 (350)

any way it takes a moment (a few min or so) for the transmission to engage once in gear.
Kinda like the trans is empty on fluid..
but the fluid is full

could it be

The TC drain back/front pump?
a clogged filter?
VB problems?

or could it be something else?

If its the TC/drain back or front pump approx what would a shop charge to fix it?

thanks

Does this happen when you first drive it or all the time? If it's the first thing after sitting over night try letting it idle in neutral for a few seconds before going in gear.

yes it happens when it it sits a while.. it has to run a min in netral before engageing into gear..

Have you tried changing the fluid and filter?

NOT YET, sopposedly it was flushed.. But the filter could be clogged.. I also would think it would have other plroblems if the filter was clogged.. draining it now..

I think it takes ATF+4.

thats what i have.. the filter looks pretty good.. i have seen worse..

I remember some yrs ago, dad had a simular problem with a 727.. and I thought he said it was a valve , (drain back) i think, it was letting the TC drain back.. there-fore every time he started it it had to re-fill and pump up.. But I looked in my 518 atsg manual and can not find such a thing.

I recall reading something about newer rigs having an anti-drainback valve in the line to the radiator/cooler to prevent that from happening.

What would happen is that valve would get plugged, and cook the transmission in short order

Sitting in neutral for a little bit is an easy fix.

Quote:

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I recall reading something about newer rigs having an anti-drainback valve in the line to the radiator/cooler to prevent that from happening.

What would happen is that valve would get plugged, and cook the transmission in short order

Sitting in neutral for a little bit is an easy fix.

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I think that was 93 or 95 and up..