'99 Chevy Suburban torque converter lockup problem

1999 Chevy Suburban 1500 w/ 5.7L 83K miles
The torque converter appears to be doing odd things! There are times the truck shutters and stumbles from a stop and shutters and stumbles, almost as
if preparing to stall, coming to a stop. It can shutter like made at times when driving at any speed until it gets to highway speeds and is then somewhat OK. Then at other times you would never think anything is wrong with the truck! It almost always drops about 300 RPMs when in a coast at any speed. It sort of feels like you are dropping to a lower gear, but just barely touching the accelerator puts the RPMs back to normal and you feel it "free up."
Running through the GM Converter Lock-up problems diagnosis, there is NO light on my light tester on Terminal "A" of the top connector off the driver's side of the tranny near the linkage cable w/ the key on, engine off. (Harness is light gray with letters A through D on one side and E through G on the other.)
There is NO light on Terminal "D" of the connector when running in OD at 60 MPH. You hear it run through all gears on the way up.
Wanting to test the Quick method for test #1 to check for 12 V at terminal "A" of the ALDL then test by jumping "A" and "F" for TCC lockup while driving at 35 MPH, if test #1 passes. How do you tell what ports are what on the ALDL connector???
Thanks, Kevin
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a 99 has OBD-2
you need to hook up a REAL scanner instead of farting around

as
any
it
60
on
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Hmm, No period. All caps in the middle ?
And this is from the same guy that says I need help with spelling ?
Lol

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OK, by hooking it up to a "REAL scanner" I hope a Chevrolet dealer's scanner is "REAL" enough!!! They found NOTHING other than a P0304 which it has thrown in the past. Can't figure that one out either, even after replacing the #4 injector while doing the intake gaskets and all of the ignition tuned up from the distrib to the plugs, but that is another story.....

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replace the fuel filter yet ?

the
almost
wrong
at
just
feel
NO
engine
at
what
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I replaced the fuel filter about 15-20K miles ago. Would have to look in my records to pin it down, but that is on my general maint. to do list again as well.

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K wrote:

    A Real Scantool is a something like a Snap-on or SPX Scan-Tool. Not the little joke units Autozone sells people.
    Sometimes you have to have the scantool hooked up while operating the vehical at road speeds to find problem. Charles
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