Help Needed Serviced My Truck and Now it is Running Rough!!!

[SJB]

It isn't a diesel, but I know you guys can still help.

This doesn't pertain to a diesel, but my '01 Super Duty w/ V10.

Despite thinking about getting a diesel, I decided I still need to maintain my current truck as well. So I recently changed the transmission fluid and filter (in pan and torque converter), changed the fluid in my transfer case, and changed the fluid in both my differentials.

After doing all this, I noticed my truck was driving kind of rough at times. Don't really know how to describe it. But it kind of of stutters (maybe even vibrates a little) when I'm lightly on the gas. I didn't really notice this before the service. Was thinking it might have something to do with the tranny (only because the service), but I don't really know. Not sure if it is just a coincidence. Everything went smooth on the service. I used the correct transmission fluid (Super Tech fluid for Dexron III and Mercon brands). I was a little worried about the brand, but the guy at the store told me it should be fine. I put in the right amount of fluid because I measured what came out. The only thing I did when the tranny was empty was put the truck in neutral (while engine off) so I could rotate the torque converter by hand to drain it. Didn't think this would hurt anything.

I also filled up the gas tank recently. Does it sound like a transmission issue, or is it just a coincidence? Could it possibly be bad gas? Any help appreciated.

 

[dennisj2003]

Do You have limited slip rear? and if so did You add friction modifier?
Usally 8oz for these rearends.

 

[iracemine]

how many miles are on the truck, and how did the trans fluid look in color and was in it?

 

[SJB]

Do You have limited slip rear? and if so did You add friction modifier?
Usally 8oz for these rearends.

I don't believe I have the limited slip. I just added the full synthetic gear oil that was suggested on the tag on the differential and my manual. I also completed the services on different days. Transmission was first, and I think I noticed it before I even completed the differentials.

 

[SJB]

how many miles are on the truck, and how did the trans fluid look in color and was in it?

The truck only has about 71,000 miles on it. The tranny fluid that came out looked pretty good. It was a little darker red, but not bad. The tranny service is pretty much a no brainer (drain fluid out of pan, drain fluid out of torque converter, change filter). Not sure where to go wrong there, if even at all. Used fluid for Dexron III / Mercon vehicles. Not even sure if it is the tranny itself, just weird that the truck is running weird now after service. Like I said as well, filled up the truck with gas all around the same time.

I've been debating on draining and re-servicing the tranny again.

If I took it to a tranny shop (without servicing it, can they test it and even tell if my issue is coming from the tranny)?

 

[dpantazis]

look at the stamped sheet metal tag that was on the bolts on the diff cover. it will give you the ratio. if it has the "L" or "LS" its a limited slip diff.

 

[SJB]

Need Advice

look at the stamped sheet metal tag that was on the bolts on the diff cover. it will give you the ratio. if it has the "L" or "LS" its a limited slip diff.

I will check the tag, but I think the truck was acting this way even before I messed with the differentials. I went to a tranny shop to have them look at it to be sure (because I was ready to re-service the tranny again). They just drove the truck (nothing else), but they said the tranny felt fine. They did notice some hesitation in the engine (I don't think it did it as bad as times when I've driven it). The guy said he felt that it was more with the performance of the engine, and not the tranny.

So right now, I'm trying to run out this tank of gas (hoping for the off chance the gas was bad), and then change the fuel filter and run some premium gas. If it isn't this, then anymore ideas out there?

(I tested a couple of things today. In park and idle, I punched the gas - it would stutter slightly sometimes initially while reving. It wouldn't choke out, but I could feel a slight stutter/vibration initially. It wasn't crisp. But at other times I could do this, and not feel that stutter while punching it. --- Again while driving around 40 mph (not only speed) I could feather the gas and the engine would stutter and I could feel a little vibration).

 

[iracemine]

yeah im gonna for with not trans or diffs as your prob also.

 

[SJB]

yeah im gonna for with not trans or diffs as your prob also.

I'm hoping that it was just pure coincidence that it happened around the same time I did the service. I had just filled up the gas tank, and then did all the service/maintenance on the truck. I'm hoping that it is just a bad tank of gas. I've gone over in my head 1000 times of whether I forgot to do something or did something wrong during the maintenance, and I can't think of anything. I'm already pretty cautious, anal, and OCD when it comes to the things I do (especially my truck). So I'm hoping that it is just the gas.

 

[fordfury]

i think its in your head, just worked on it now you notice something isnt right but probably been doin it all along. but sounds to me like it would be a engine thing not what you did fresh oil never hurts anything but a little more details on what its doing and when its doin it. right before a shift or during a little accel, or at a certain speed would be help full.