When I'm going about 30mph down a straight road with my foot on the accelerator steadily to keep it going 30mph, my truck jerks minorly forward every couple seconds. It's like I would be revving it up while in gear or something. It's been doing this ever since I can remember, which would be a little under 2 years. I was thinking my fuel filter could be bad/clogged and making the fuel use be inconsistent, but the rpm's don't change. Any ideas?

 

how many miles on the truck?

 

It's an 01, you probably already know, alot of miles, haha, 38,000

The wierd thing is that it only does it around 30mph, on the highway it's not there

 

First, make sure that you're not feeling the compressor cycling. This will feel like the power gets a little stronger and weaker every 15~30 seconds. The A/C compressor operation is enabled in AC, Max AC, Floor/Vent, Floor/Defrost and Defrost. Set it HVAC mode selector switch to OFF and see if it goes away.

Another possibility is a surge. This happens much more often than when the A/C compressor cycles. It feels like very light random bumping every second or two. Surging is usually caused by too much EGR flow or a lean or poorly controlled air fuel mixture.

Since you have a 2001, the #1 suspect is a bad DPFE sensor in the EGR system. 2nd would be a lean condition caused by dirty injectors, clogged fuel filter, dirty MAF or whatever.

Ever have a Check Engine Light? Any codes stored?

 

I never got a check engine light.
It sounds pretty much like the surge you mentioned.

 

lol well you beat me. I have 37,000

i would go to an auto store and buy some of that injector cleaner that you put in your gas tank and try that.
Although my opinion about that stuff is if it can make it through all your fuel lines without eatting through, then its probably not strong enough to clean injectors.
But it will clean something out and start with the easy things.
All you have to do there is spend a few bucks to buy it.

If that doesnt work then i would try the fuel filter.

 

The injector cleaner, i put 2 bottles of some decent expensive stuff from autozone in with only 1/4 tank, you're supposed to use it with 20gallons, so I figured with 1/4 tank it would work better, and I ran the tank down till the gas light came on. Didn't change anything, did it a few times the way you're supposed to.