patrick66
Old Man with a Hat
Got a little problem with my 1987 GMC 1500 with automatic trans. It leaks like a stuck pig, and I can't figure out where it's coming from. I did a transmission fluid/filter change on it recently. The capacity with converter is 13 quarts. I put eight in it, as I didn't drain the converter. New filter in. New gasket on. Start the truck and let it idle for a time. Life's good...for a minute or so. Now, I have fluid leaking onto the shop floor like mad! I made sure the dipstick tube had a new O-ring on the trans end, but it doesn't appear to be leaking there. It leaks whether the truck is running or not. I saturated a sheet of cardboard I had stuck under it to try to see where the leak is from, and that was not any help at all.
No leaks at the tailshaft.
So, here is what I figured...either the dipstick seal is crap, despite the new O-ring. Or a loose fitting on the side of the transmission (there are two on the passenger side), or the speedometer cable pinion seal. Or the torque converter??? It has sat for about a week now, and I am not seeing any further leakage, so it's likely dripped below the point of the leak. Gonna start it up tonight, move it around a bit in the yard, and park it over another bit of cardboard and see if I can figure out the leak source.
This is an amazingly straight and rust-free truck. It needs tires, a windshield, and working brake lights to be street-legal. I'm a big fan of the '73-'87 GM pickups, so it's a "work on it when I feel like it" project truck for me. My son can't afford to keep this old square-body going, so I bought it from him and sold him my '01 Ram Club Cab. The Ram is dependable and very clean and solid.
No leaks at the tailshaft.
So, here is what I figured...either the dipstick seal is crap, despite the new O-ring. Or a loose fitting on the side of the transmission (there are two on the passenger side), or the speedometer cable pinion seal. Or the torque converter??? It has sat for about a week now, and I am not seeing any further leakage, so it's likely dripped below the point of the leak. Gonna start it up tonight, move it around a bit in the yard, and park it over another bit of cardboard and see if I can figure out the leak source.
This is an amazingly straight and rust-free truck. It needs tires, a windshield, and working brake lights to be street-legal. I'm a big fan of the '73-'87 GM pickups, so it's a "work on it when I feel like it" project truck for me. My son can't afford to keep this old square-body going, so I bought it from him and sold him my '01 Ram Club Cab. The Ram is dependable and very clean and solid.
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