Bear with me as I try to describe my issue. I have a 2010 Dodge Ram 1500 with about 315K miles on it. I am the second owner, but bought it at 50k miles. has run great with no real issues despite the high mileage. Within the last month or so, I have noticed it strongly vibrating and shuddering when it hits 1500-ish RPMs. I am noticing a loss of power. I can get the power and RPMs up, but it takes a heavy foot. Once the RPMs are up, it is fine and even hauls a trailer fine so long as I am pushing the gas pedal down, but cruising along, it's feeling weak. I am also noticing the RPMs are wanting to drop lower than what I remember to be normal when I am driving under 60 mpg. around 1100 rpms. My 2013 chevy coasts along at this speed around 1500-1700 rpms. I am also noticing if I let off the gas, there is an almost immediate down shift and drag, even going downhill. I don't think my truck should be slowing down when going downhill... and it certainly didn't do it before. I have replaced the spark plugs and that may have helped a little, but not 100% It's not the same sound or feeling that the truck makes when the MDS kicks in, but I'm not completely unconvinced that the MDS could be broken. At this point, I am just buying and replacing whatever google says it could be. I figured I would join here and ask my specific question. I am also wondering about transmission fluid. I have never changed mine and someone told me if it's never been changed and the mileage is that high, I shouldn't change it... Should I try that? I have a relatively new fuel pump. Replaced probably 6 months ago...oil and filter was changed less than 3000 miles ago... new brakes just put on and front brake caliper. I think that covers recent replacements. about 6 months ago I did get a new camshaft, but the truck returned running perfectly after that.

 

Are your brakes dragging? Check engine lite on? Feeling any misfires? What plugs did you install? How old are your O2 sensors?

 

I don't hear any noises from the brakes, but that is not to say they aren't dragging.. They were just replaced. Not sure how to check them to see if they are dragging though or if that would be the issue that is causing it to vibrate only at 1500 rpms? No lights on and I don't think its a misfire. I have had it misfire before and this is not the same feeling. The plugs came from O'rielly's. That's all I know. And I have no idea about the O2 sensors. Not sure if they have ever been replaced. I would have to ask my dad (he does all the work on my truck aside from basic "easy stuff, which my husband does. Dad Owns a mechanic shop. hasn't had time to deal with this particular issue and is annoyed with my phone calls at this point because he swears it drives fine, but I know it isn't.

 

Need to take a page out of my wifes book. "Here, this one is broke, YOU drive it." That tends to prompt me to figure out the problem, and deal with it.

Might try unplugging the front O2 sensor(s?), and see if the problem goes away. With that many miles on it, I would not be at all surprised if they weren't getting lazy in their old age.

 

I am driving my husband's truck currently, but I haul a horse trailer and the chevy SUCKs at hauling. If it were a slight decrease in power over time, I might be inclined to think its just getting lazy, but this was basically over night, but I am sending that to the husband to give a try!

 

Are you related to my wife?

Are the cats still on the truck?? Wonder if one of 'em failed.....

 

Cats are still on. Wouldn't a failed one make the check engine light come on?

 

But also, your wife sounds fantastic and we should be friends! LOL

 

Not necessarily. Easy test though, remove the front O2 sensors from the exhaust. If the cats are clogging up, it'll run better with the sensors out. (of course, it'll be louder too..... and set some codes)

I think so too.

 

Going to try the O2 sensors today. Will report back!