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1968SWBBigBlock · 11-09-2008, 06:21 PM

Drain back from the TC overfills the cranckcase - the lowest point seal after the tranny pan is the dipstick tube.
Most dipstick tubes are mild steel with a crimp in the tube and an oring for a seal
These orings dry rot over time and allow the tranny to leak after the truck sits.
It may not do it all of the time depending upon location of the pump and torque converter

11-09-2008, 06:21 PM	#7
1968SWBBigBlock Active Member Join Date: Oct 2006 Location: Ohio Posts: 1,643	Re: TH 400 Torque Converter Drain Back Solutions? Drain back from the TC overfills the cranckcase - the lowest point seal after the tranny pan is the dipstick tube. Most dipstick tubes are mild steel with a crimp in the tube and an oring for a seal These orings dry rot over time and allow the tranny to leak after the truck sits. It may not do it all of the time depending upon location of the pump and torque converter __________________ 1968 SWB 454 + .040, 490HP x 540 FT pounds of Torque 10-1 Kb Forged pistons, recon rods w/ ARP wave loc bolts 781 heads Ported with 2.19/1.88 SSTvalves Lunati 60204 cam, Micro Trol lifters, Ported Edelbrock Performer Rpm manifold armor coated, Pertronix Triple Strike Ignition Holley 770 Street Avenger carb,Headers armor coated Built by Watson Ruppel Performance in Sarahsville Ohio. Hardshift Tranny Built Turbo 350,TSI 10" 3000 stall 12 Bolt Eaton Posi 4.10 Richmond Gears moser axles 18.5" x 31" Hoosier Pro Street Radials ET Classic 5 Wheels - polished Power Steering, Power Brakes,Disc Brakes,Tach & Gauge Dash, Tilt,Factory Air (gone) Custom Paint & Body Work Special thanks to my wife, my son and my money tree