I posted a similar thread over in engines but thought I would post here too.

I have a 1997 F150, 5.4. CEL is on, and first time it read a "slow response" from the O2 sensor, the next time it read "lean, bank one." When I drive, I occasionally get a shudder, especially at 30-50 mph, almost like a slipping clutch in an manual tranny. When I towed a camper that weighed about 3700 pounds, it shuddered horribly. And it only got about 8 mpg. Around town I usually only get about 10 mpg. I thought this might be a slipping tranny or torque converter, but also thought if it is reading lean, it could be a fuel issue.

My question is this - if the transmission or torque converter is slipping, would there be a code for that when the check engine light is on? Or I am going to just be searching to fix the lean code/O2 problem, then figure out it is the tranny as well? The truck has 114k miles on it. Any help you can give would be greatly appreciated.

 

Always fix all engine problems before fixing transmission problems. If the trans was slipping it would die very quickly and set a code and flash the OD light.

 

Great thanks. I will take care of the engine first. You say the truck would actually just die if the transmission was slipping? Wow, that is new to me. Thanks again.

 

Not the truck, the trans. A slipping trans will not live more than several seconds. The amount of heat generated by a slipping clutch or band will burn up in a VERY short time.