Truck runs good first thing. After warms up seems to slow trying to downshift , going uphill, passing. Even at stop light it hesitates shifting.
My truck has 404000 miles.
My truck has an automatic transmission. I've changed solenoids , fluid and filter.
Hello - I think your transmission sluggishness is due to high mileage, and low internal hydraulic pressure due to a worn primary pump. Low fluid pressure will make gear engagement slow and weak, with slippage during shifts in extreme cases. Since you have changed the fluid and filter (assume fluid level is correct - check to be sure), hydraulic pressure is the next most likely cause. I would recommend a transmission inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
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