350 dogging under even slightest load

[Joe25da]

1984 gmc 3500, m code 350 4bbl sm 465. Lately the truck has been struggling pulling my small 4x7 landscaping trailer with my 36" and 21" mowers. Total weight maybe 1000lbs. Lots of hills here and I'm lucky if I can get second gear, need some momentum and rpm's or it just falls flat. Also noticed when shifting to 2nd and 3rd the engine misses for a second till the rpm's pick up. Now I'm not shifting too soon, I let it wind up a bit. I replaced the fuel filter 2 months ago. Did plugs, wires, cap, coil and rotor last week. Haven't checked the timing, also haven't paled with carb yet

[rich weyand]

Check your timing.  If the disti is not clamped down tight it can drift retarded, and act just like you are seeing.

[Joe25da]

Sounds true. Seems worse since I replaced the parts

[BigBoy1981Toys]

I agree, also could be timing chain stretch depending on mileage, if so i should be able to get the difference out by turning dizzy while using a timing light etc... could be alot of things now that i really think about it, lol but i agree with rich above. Usually a sudden change in behavior without any "warning" signs immediately before hand, was caused by something that was repaired. Its amazing how sometimes i forget some lil detail putting something together, that i know better n have done countless times but i fudge it none the less, lol good luck

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