Since last week my truck start to CHUG when I drive it at any speed, it look like the transmission shift for no reason and send a signal to the engine to drop rpm. If I put the transmission on neutral I get the full rpm but as soon I put it back to drive it start to chug. I clean the conectors on the transmissiom and on the conector where the gas pedal sensor is and put dielectric on the conector, I found nothing wrong there out of some oil in one conector. The transmission fluid is good. Last night I make the truck sleep in the garage, this morning it was working fine, but after work on my way back home it start again, we have some snow here and the first time it start to do it it was raining, but some raining day it dont do it, so I dont think that wheather have something to do with it, My truck is a 2004 with a AirDog 150, everything else is stock.

Error Codes?

No error code, no check engine nothing....

I'm hoping Wild & Free shows up soon but I'm going to bet there is a band adjustment or something that is calling for torque converter lock up too early. I was hoping for a error code to point me in a direction. But being the trans appear to be shifting early that could very well cause it to chug. Next time it occurs take note of the RPM's and speed.

I change my fuel filter and water separator yesterday, I wait to drive it to work today see if that's the problem, if it to it again I will check for speed and RPM. Thanks!

My first thought was fuel filters, so hopefully that fixed it! Do you have a fuel psi gauge?Hopefully you have read the posts talking about filters and are running a Baldwin BF1275 and Donaldson P551315 on your AD.

No I dont have a Fuel pressure gauge, I want to instal one but I dont no if it's better to put a mecanical one or to wait and buy a electronic one. If somebody can give me any advice for with brand to instal... Since I change my fuel filter and water separator my truck run like new... I hope that was the problem.

While they are more money I prefer electrical. They don't seem to have the issues that mechanical have, or can have.

My truck start to chug again today, it was fine for a week. No code show up, today it's

- 15 and snow fall. I have no clue where to start to check for that snag...it do the same thing as before, gear shift for no reason an I can't get faster than 60 Km/h...

--- Update to the previous post...

Tonight after diner I drive my truck and I beat the crap out of it and it drive like new. I do a lot of stop and go, drive it in tow/haul mode, in drive, 2 and 1 speed selection, nothing happen. This truck is pising me off right now. I see on other tread that some guy have problem with a selenoid in the transmission, I dont now if this is my problem, a bad selenoid, if somebody have any advice, help is welcome.

Did you check for codes or assume ther are none because the CEL is not on? It just seems like the truck ought to be telling something.

I check for codes last week, I will check again tomorow morning. I use a OBD II reader to check the codes. Comeback tomorow with what I found...

The only reason i asked is because some folks think if the CEL does not come on that there are no codes. But it still seems like your truck ought to be talking to you.

i have heard of "soft" codes being thrown and stored but not activating the CEL

Not sure what year you have. Sounds like it is an automatic though. I know my tranny acts weird too if my batteries have bad connection or they are getting ready to go south.

My truck pop a code today P0720 (Output speed sensor circuit malfonction) I dont now what is that system for, is is the speed probe for the speedometer. I dont now if that system can cause my trouble. If somebody already have that code and now where I have to start for troubleshooting help is welcome. My truck is a 2004 with a auto trany, the only mod is a airdog 150. My 2 batterie are new and I check for a bad ground and everything look good on that side

it is a transmission code but i dont know how to deal with it. it is in the trouble code forum with trouble shooting.

I founf that this code can be related to the Output speed sensor, this sensor monitor the output shaft rotating speed. The sensor cost is 37$ I will try to replace it and see if it fix my problem. Keep you inform...

Since I change the output speed sensor the truck have no problem, I hope is fix for good.

happy to hear you got it fixed.