I have a 2004 F-150 Lariat with a Rousch supercharger. My check engine light has been on for about a week now. And just yesterday I was driving home going about 50-60 mph when I started feeling my truck kind of bouncing/slightly jerking forward. Misfire maybe? I'm already taking it to the shop in a few days, but I'm nervous to drive it. It's the only way I can get to work. My RPM doesn't bounce around when this happens, either. I already knew why my engine light was on before, because I have one or two O2 sensors out. Pretty easy fix, but this that happened... So I immediately called the shop and asked for them to schedule me in to replace all my spark plugs and wires and all new O2 sensors.

Also, whenever I am making slow turns, either from a dead stop or at least under 30 mph, under acceleration, my rear ended feels like it's shuddering and my steering wheel is vibrating. This only happens on slow, left/right accelerated turns. Rear axel packs? I picked up some friction modifier, all I need to do is put it in. But I'm afraid I'm dumping too much money into this truck.

Any help is very appreciated. Thanks all

 

Did u buy it with the sc? Installed?

First things first you need to go get the codes pulled and see if their is a misfire code

The rear end problem, you need do a rear end service, drain and fill with 75-140 and 6-8 oz of friction modifer


Your truck doesnt have spark plug wires you have COPs (coil on plug) when was last time plugs were changed? How many miles on truck

What kind of maintenace has been done? Could be fuel related, like FPDM under spare tire or fuel filter

 

Be careful telling a repair service to replace parts; they will do what you want, but it might not fix the fault, and then it will cost you more money. They are in the business to make money, so they will do what you request.
Instead do as grss429 mentions; get the codes read. If you do not have a code reader or tuner that connects to the OBD-II connector (under the dash to the right of the steering wheel), go to an automotive parts store and ask them to read them for you. Many will do this service free of charge; just don't let them pressure you to buy parts to correct the fault.

Post the codes here.

 

Codes say that my O2 sensors are bad and that's about it...

 

But that confuses me, because how could that make my engine misfire? At least I think it's a misfire. It said its running too "lean", but when I have my truck running my buddy who's good with vehicles says it's running too rich because we can literally smell the fuel running through the engine, even when I'm parked with the engine running. Friday I'm getting all my O2 sensors replaced by him, he knows trucks and has a gift with working on vehicles so I trust him. Hopefully after Friday it runs brand new. And yes, I purchased my vehicle with the supercharger installed. It's almost a brand new supercharger.

 

so you today/yesterday you pulled the codes and all you have is 02 codes? or have you not checked them currently

 

Change just the 2 upstream O2 sensors closest to the exhaust manifolds. Easy peasy and only takes 30 minutes or so max. Then change your rear gear oil with some full synthetic 75W140 and a bottle of XL3 Motorcraft friction modifier. Problem solved. Why let a shop do it????

 

The shudder/hesitation/jerking at around 55 mph is more than likely a misfire, but won't necessarily throw a code. I had the same issue, as many others on here have (lots of threads about it). You can do a scan to see which cylinder is misfiring or just replacing them all. Since I had 135,000 miles on my truck, I just replaced all plugs and COPs. Took about 3 hours or so to do myself, less than $200 in parts and tools. It'll be at least twice that if a shop/dealer does it and a lot more if any of your plugs break.

 

^^^this is had this same issue changed just plugs made it a little better changed cop's completely gone

 

Yes all I got was O2 sensor codes.