Occasional P1870
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Joined: Mar 2025
Posts: 2
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Occasional P1870 2001 Chevy 1500 5.3L ~135,000 miles Stock
The truck is used as a work truck, just hauling light loads, rarely ever a trailer. Drive 200-500 miles a day around town/highway, making multiple stops. Owned it for many years, and only had this issue for about 6-8 months. About once or twice a month it'll throw a P1870, and shift very hard (maxes out line pressure I presume), no CEL, and no other codes.
I installed the Tekpak/Fixall P1870 replacement TCC valve shortly after this first started (installed w/o removing valve body). TCC Solenoid ohm'd out good, pan was fairly clean, no metal debris, and fluid was fine (presumably original fluid, as knew the original owner). It didn't seem to help any. It seems to happen less in the winter months, but that could just be due to driving the truck a bit less.
I have to replace the rear main seal/cover as they're leaking quite a bit, and was wondering what's the likelihood of it just being a bad torque converter? I don't really mind having to remove the transmission again to rebuild it, if it ends up not being the tc, but figured I'd ask for some insight before doing such.
Thanks!
The truck is used as a work truck, just hauling light loads, rarely ever a trailer. Drive 200-500 miles a day around town/highway, making multiple stops. Owned it for many years, and only had this issue for about 6-8 months. About once or twice a month it'll throw a P1870, and shift very hard (maxes out line pressure I presume), no CEL, and no other codes.
I installed the Tekpak/Fixall P1870 replacement TCC valve shortly after this first started (installed w/o removing valve body). TCC Solenoid ohm'd out good, pan was fairly clean, no metal debris, and fluid was fine (presumably original fluid, as knew the original owner). It didn't seem to help any. It seems to happen less in the winter months, but that could just be due to driving the truck a bit less.
I have to replace the rear main seal/cover as they're leaking quite a bit, and was wondering what's the likelihood of it just being a bad torque converter? I don't really mind having to remove the transmission again to rebuild it, if it ends up not being the tc, but figured I'd ask for some insight before doing such.
Thanks!
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Joined: Mar 2023
Posts: 1,824
Likes: 1,162
From: BERWICK PA
If you used the fitzall valve then it would have to be the converter or badly worn bushings, Out it must come.
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Frank formerly of Performabuilt, Now just me, What can I build for you today? Call or message me. Click sig pic for my facebook
Frank formerly of Performabuilt, Now just me, What can I build for you today? Call or message me. Click sig pic for my facebook
