Author Topic: TH350c lockup converter slipping in and out  (Read 3830 times)

Offline sleepchamber

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TH350c lockup converter slipping in and out
« on: December 05, 2011, 04:35:00 pm »
Anyone ever had the lockup converter slip in and out?  Engages at 45mph and seems to stay engaged as long as I stay at 45mph....anything over and back down to 45mph the converter slips in and out of engagement constantly.  This is an '85 C10, 305ci, non-computer controlled carb and distributor.
1985 Scottsdale C-10

Offline VileZambonie

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Re: TH350c lockup converter slipping in and out
« Reply #1 on: December 05, 2011, 10:17:14 pm »
Fluid level and condition is good? Low vacuum switch is connected and detent cable properly adjusted? TCC Brake switch is OK?
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Offline sleepchamber

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Re: TH350c lockup converter slipping in and out
« Reply #2 on: December 13, 2011, 11:51:21 am »
Fluid is clean and full...the vacuum switch is connected...detent is not connected.  What is the TCC brake switch?
1985 Scottsdale C-10

Online bd

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Re: TH350c lockup converter slipping in and out
« Reply #3 on: December 13, 2011, 01:24:50 pm »
Check the switch adjustment (common cause of the symptom you're describing).  The switch is depressed by a metal bracket bolted to the brake pedal arm, behind the dash.  If not adjusted correctly, minor movement of the brake pedal while driving will cause frustrating converter disengagement.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
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Offline sleepchamber

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Re: TH350c lockup converter slipping in and out
« Reply #4 on: December 13, 2011, 01:31:19 pm »
Will check this when the weekend comes....thanks for the suggestions.
1985 Scottsdale C-10

Offline sleepchamber

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Re: TH350c lockup converter slipping in and out
« Reply #5 on: December 19, 2011, 09:50:05 am »
It was....a dry-rotted vacuum line to the switch behind the brake booster.  Went ahead and replaced all of the vacuum lines.  Thanks dudes.
1985 Scottsdale C-10