1999 Chevy Astro MANUFACTURER CONTROL TRANSMISSION CODE #P1

MCAUTODOC

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1999 CHEVROLET ASTRO
6 CYL
2WD
AUTOMATIC
370,040 MILES

VIN #1GCDM19W7XB149698

I'm reading this code but only have a code reader, don't have a Tech II or similar scanner to make checks or activate sensors. The below freeze-frame info is what I was able to read; need guidelines/suggestions on how to proceed with diagnosis & repair.
THROTTLE POSITION) 2.2
ENGINE RPM) 1971
LOAD VALUE) 17.6
MAP SENSOR) 64
AIR FLOW RATE) 30.76
COOLANT TEMP) 208
SHORT TERM FUEL TRIM 1) 0.0
LTFT 1) 5.4
STFT2) 1.5
LTFT2) 6.2
STFT3) 50.0
LTFT3) 78.4
STFT4) 89.8
LTFT4) 35.9
VEHICLE SPEED) 63
FUEL SYSTEM 1) CLOSED
FUEL SYSTEM 2) CLOSED

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MCAUTODOC

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33 POSTS

P1870 MANUFACTURER CONTROL TRANSMISSION CODE

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Tuesday, September 8th, 2009 AT 8:43 AM

SERVICE WRITER

MECHANIC
9,123 POSTS

That code description is "Transmission slipping". The pcm detects slip speed greater than 50 rpm.

Are the wheels/tires stock? Are the size of the wheels still the same as originally installed?

I assume they are original.

This is probably a valve body sticking in the transmission. Hopefully the fluid is a translucent pink color and the filter has been changed at reasonable intervals. I doubt the tranny is original at that mileage. IF it is I would look into a rebuilt one.

Other possibilities may be the stator bushing on the pump where it rides on the input housing ,would have excessive wear. was there brass in the pan when removed ? Also have had to replace the pump as the solution. Torque converter is another suspect.

I've heard that adding a shift kit may take care of this, but I haven't taken that path before.