Author Topic: 700r4 shifting and locking up too early.  (Read 2708 times)

Offline 1976Scottsdale

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700r4 shifting and locking up too early.
« on: November 20, 2007, 10:49:36 PM »
My friend just bought a 1987 Chevy R-10 pickup.  It is a longbed, 305 TBI with a 700r4 and 41000 original miles.  We just had the trans rebuilt because it was hitting overdrive at 25 miles an hour an would not quit.  It had been fine until he installed a 195 thermostat in place of the 180 he had.  As soon as he did that it started shifting too soon.  Now, it will run fine when cold, but as soon as the trans warms up it locks the converter at like 20 miles an hour and keeps cycling in and out.  The converter, lockup solenoid, and stuff are all new and we had the rebuild done by a reputable shop at a cost of $1200 dollars.  Could the trans temp switch in the pan be bad?  I ask because I had to at one point use a torch to notch his crossmember to get the pan out without removing the trans mount and it got a bit warm in that area(did not melt any wires, the pan and switch were too hot to touch though.  So, could that switch be bad and causing him problems now?  He is also going to swap a 180 thermostat back in since his 195 heated to like 240 the first night he had it in.

Offline 79shortbed

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Re: 700r4 shifting and locking up too early.
« Reply #1 on: November 21, 2007, 04:02:07 PM »
adjust the kick down cable

Offline Captkaos

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Re: 700r4 shifting and locking up too early.
« Reply #2 on: November 21, 2007, 05:27:52 PM »
I would keep the 195 stat (if that is what it is, the TBI is designed to use that temp)
I would also adjust the TV cable.