Hey everyone just looking for some ideas on what might be wrong with my truck. Its an 2001 5.4 supercrew 4X4 with right at 140,000 miles. Last year the truck got to where it was misfiring and shacking and shuttering and sometimes would even cut out driving down the road. After posting a thread on here I replaced the cops and plugs. Went with the cops from global off of ebay and replaced the plugs with the motorcraft replacements. This took care of the missing and shakes but the truck seems to have no power and the gas mileage has gotten awful around town I get 11mpg and when I pull my 16ft trailer loaded with lawn equip. it gets a little over 7mpg. What could be the cause of the power loss and what might I try to bring some life back to my old truck.

Thanks
Lynn Sesco

 

I'm going to assume you have done little to no maintainence on your truck





time for tranny flush, coolant flush, differential check, o2 sensor change, plugs, clean your air filter and MAF, do the gotts mod, grease your wheel bearings and see where that gets you

 

No never have done the tranny flush or coolant flush or 02 change but truck has new plugs and I am running a K&N filter and already done the gotts mod. About the tranny flush i'm pretty sure that I read on this forum about the tranny shutter which my truck has that if you do the flush that this could cause the tranny to go out completely.

 

Maybe clogged cats?

 

I agree, time to catch up on all that maintenace.

Then start your troubleshooting...

 

Should I take it to the dealer for the tranny & coolant flush or should my local garage be able to do this. Also what brand O2 sensors should I replace the old ones with.

 

bosch sensors, you're tranny is on it's way out so it's days are numbered anyway...

 

A muffler shop can check for clogged cats and exhaust restrictions with an infrared sensor.

 

That tranny shudder may well be a low grade missfire. I would start off with the plugs and I'd get the E-bay coils for $75 Motorcraft plugs I'd clean the throttle body replace the o2's. Then if itwhen all that was done if the shudder was gone I'd replace the tranny fluid.I wouldnt bother if it wasnt your gonna need a rebuild.