Truck shuts off when going from drive to reverse

[1984K10]

I posted this here because I figured it's a transmission problem but I'm not sure.

I have an 84 K10 with a carbed (edelbrock 650cfm) 350 engine from an 88 pickup. The truck runs and drives well (except for minor tranny slip) but sometimes when I go from drive to reverse or reverse to drive the choke light comes on and the truck shuts off. I've noticed that SOMETIMES, it helps if I press the brake pedal all the way to the ground. Also, the times it doesn't turn off, either the rear differential or the driveshaft clanks. Has anyone had this issue on their SB? Could it be something as simple as a differential fluid change? A guy I know said it's something in the steering column but I thought I'd ask y'all too.

 

[89Suburban]

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[towjoe]

how hard is it to get it to go in drive when it's warmed up? if that's also a problem the tourqe converter is probably not disengaging correctly. real simple way to make sure its not in truck electrical is to unplug transmission and try it. could be the reverse lights are shorted out, but if there unplugged that will eliminate that issue. tourqe converter could be shorted out in lockup mode and not releasing to.

 

[1984K10]

how hard is it to get it to go in drive when it's warmed up? if that's also a problem the tourqe converter is probably not disengaging correctly. real simple way to make sure its not in truck electrical is to unplug transmission and try it. could be the reverse lights are shorted out, but if there unplugged that will eliminate that issue. tourqe converter could be shorted out in lockup mode and not releasing to.

Once the truck is warmed up it isn't too hard to get 'er to go. I'll try unplugging the transmission though. Is there any write ups on how to do this or is it pretty straightforward like just get under the truck and look for some cables by the tranny and unplug them?

 

[1984K10]

Okay i got under my truck today while looking at somethin else and I found a disconnected cable. I haven't looked to see where it should go but I got a picture of it. It's sitting between the transmission and transfer case. I'm the first pic I'm pointing at it

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Sorry for the ****** quality, this app I'm using limits the resolution of the pics.

 

[MrMarty51]

Looks like a one wire connector, yes ???

 

[chengny]

TSB for the 700-R4 in that model year range

NUMBER: 86-B-79

GROUP: 7A-Automatic Transmission

DATE: May, 1986
SUBJECT: ENGINE STOPS RUNNING DUE TO TCC ENGAGEMENT WHEN SHIFTED FROM PARK/NEUTRAL TO REVERSE OR DRIVE

MODELS: 1982-86 LIGHT DUTY MODELS WITH THM 700-R4 AUTOMATIC TRANSMISSIONS
Some 1982 through 1986 vehicles equipped with a THM 700-R4 automatic transmission may experience a condition where the engine stops running or lugs when shifted from Park/Neutral to Reverse or Drive.

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This condition may be a result of torque converter clutch engagement when either gear range is selected, and may be caused by improper operation of the converter clutch valve, located in the pump cover (Refer to Figure No. 1).. If this condition exists, inspect the converter clutch apply valve for the following:

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^ Not properly seated or missing retaining ring (item 225). When installing this retaining ring make certain the rounded edge of the ring faces the valve stop (item 226). Refer to Figure No. 2.
^ Nicks or burrs in the converter clutch valve (item 227) or valve bore.

^ Missing, broken or damaged converter clutch valve springs (outer spring item 228 and inner spring item 229).
IMPORTANT: Prior to servicing the pump assembly for the above condition, make certain that the engine is properly tuned to specifications.


Refer to the appropriate Service Manual for removal and installation procedures

 

[1984K10]

Looks like a one wire connector, yes ???

Finally got under her again to take a look. It has one wire attached but another laying off to the side that seems to have been pulled off or something