I've searched and not really found my question or answer.

I experience this when going uphill only - the truck feels like its hesitating or slightly jerking for lack of a better description.
If I force it to downshift it runs fine.
It almost feels like the trans cant make up its mind but its not really shifting.

Hope that makes sense..... I do have the fluid to drain and fill the trans fluid and plan on doing that.

Thanks.........

 

Hesitation under load is typically caused by the fuel injectors not adding additional fuel and causing the mixture to go lean causing misfires. The lean condition also puts your ignition system under more load, so a spark which is normally fine, but weak, will become too weak to fire. So it could be your fuel injectors, ignition, or components that control that system. I would start with inspecting for leaks in vacuum lines and then see if the MAF is working, as MAF equipped vehicles are really sensitive to vacuum leaks causing these kinds of things.

 

Thanks for the response.

I'm note quite certain I understand why it only happens under load and giving it more pedal and forcing a downshift makes it go away.
If it was a MAF and/or vacuum leak issue, would I not encounter this more often during normal driving?
I drive 25 miles one way in rolling hills on I85 in SC to work and back and it never does this.
Only when I hit a grade where I'm somewhere between current gear and downshift.

However..........I'll have to check my records, but believe I'm ready for spark plugs/wires. I pulled a plug a week or so ago and it looked ok but the center node was rather worn so I think its time.

 

That is odd, do you encounter it at all when you accelerate away from a stop?

 

Nope....

 

Typically, a car that jerks going uphill is having problems with the fuel pump being too weak to force fuel up an incline. Is it actually physically jerking or just down on power?

 

It feels more like a hiccup - but like I mentioned, until I give it a little more gas and force a downshift, then it runs fine.

 

Stock wheels and tire size?

 

Yes....

 

Throttle Position Sensor? Plugs?