Hello everyone. Im new here so please forgive me if this has been covered.
My 2003 4X4 5.4L with 83,000 miles has developed a bumping feeling when you are barely pushing the accelerator at highway speeds. The best way I can describe it is if you are in a hilly area, you let off the gas going down a hill and when you start up the other side slightly pushing the gas pedal, it feels like the transmimssion slips out of gear and back in. It may do this a couple of times before continuing normally. If you give it extra gas it will not do this even if it does not downshift. Also if overdrive is not turned on it does not happen. I recently replaced the tires from 285s to 305s. I don't know if this would have anything to do with it but I noticed it right after replacing the tires.

Thanks,
V Star

 

Just a shot in the dark, but do you have a check engine light? Sound like you may have a slight miss.

 

What is it with new tires -cowincidence? I purchased a set - New BFG Fortara's - I developed a shudder prob the sam afternoon -WTF ?? There the same size - My old burnout tire was at about 1/16 tread , opposite side was close to 1/2 inch tread and they were diffrerent makes , but the same size according to the sidewall - of course that wasn't exact , but would new tires cause thin much havoc?

 

What is it with new tires -coincidence? I purchased a set - New BFG Fortara's - I developed a shudder prob the same afternoon -WTF ?? There the same size - My old burnout tire was at about 1/16 tread , opposite side was close to 1/2 inch tread and they were different makes , but the same size according to the sidewall - of course that wasn't exact , but would new tires cause thin much havoc?

 

It really sucks after Tire purchase - that's a big enuogh expense and now a trans to

 

The engine light is not on. What is shudder? Can it be fixed?

 

It's a slipp grab , slipp grab, slipp grab sensation Well sorta lol , I guarantee you'll know what I mean if you have one.

As far as fixing - Yes and No - It depends where it's comming from exactly , No one usually answeres that question there know way of knowing it's origin. You have to experiment a little and again know one will instruct this because it could cause complete failure and who wants to be responsible for that ...

I'll give it a shot though , I don't believe this will hurt and I've talked to few guys offline about it. LubeGuard makes good products and they have this trans doctor stuff that is recomended by the Pro's - It's suppose to stop converter shudder , it hasn't mine - not completely yet , but it may in the future . I've been told -"like the rear end , it takes time to cure a shudder issue once the correct additives are in place" .

You know as much as I now LOL

 

That is kind of what it feels like. Like its slipping out of gear then back in real quick. If you give it gas it stops. Can it be fixed? Or is it something terminal?

 

Thanks for the info. Anyone know what could be the cause? Would a flush at one of the quick oil change places help or is that a bad idea?

 

Actually theres only one post I ve seen so far where flushing has eliminated there shudder - they had the dealership do this - According to what has been documented here - that has worked in one ocasion . You'll be lucky to get any answeres here about that topic.

 

I have 2000 5.4 2wd auto 156k mine just started doing the same thing I already tried changing filter and complete fluid exchange that did not work. I guess I will look in to anti slip additive. I would like to fix permanetly and I do not thank transmission is worn out there is no metal on the pan magnet. I noticed this just like you said while coasting down a hill and then slightly accelrate afterwards it is almost like a manual trans would do if you try to accelerate in to high of gear. I am just wondering if while going down hill should'nt the auto trans downshift to a lower gear. Maybe it used to and some relay or adjustment is @%$*^#UP and it is tring to accel in to high of gear. I guess this would be no help to you but maybe draw someones attention that has fixed this already.

 

Could the EGR being clogged do this?

 

I might be overlooking something but I dont see the egr valve causing something like this.

 

Try dr. tranny by Lube guard - a quality auto parts supplier will have it - Carquest has it - if you have one around your area.


BYRON661 -
Just pull your EGR hose and suck it into your trans - NO NO JUST KIDDING

 

Thanks, I will see if I can find some of that.