loses mph's at high rpm

I purchase a 96 dodge ram 1500 with the 5.9L magnum engine with approx 158000 miles about a month ago. I had the transmission flushed and inspected and was told it was in good shape and should have it flashed. I took it to a dealership and had it flashed. While at the dealership I had them look to see why my check engine light was on and they told me it was the oxygen sensor and replaced it. They also changed the sparkplugs, I had told them that the truck seemed be bogg down if I would try to kick it down to pass anybody, They thought that would take care of the problems. Every once and a while when the engine is idling I hear a rattling noise close to the cataystic convertor. Do you think that could be causing the lack of power? also when I kick it down the rpms while kick up to about 4100 rpm's and I will lose mph speed until I let off the gas and bring down the rpms to below 3100 rpms and then my mph's will increase.

sounds like your catalityc converter is plugging up tap on the converter with a rubber hammer to see if you can make it rattle

Yup, a common occurrence on the 96, time for new cats.

I have an appointment to have it changed out tomorrow, I will let you guy's know what it is like after that. Thanks for the response. :) :)

And.....the answer is......?

YES it was the converter !!!! {maybe} hee hee !!!

Yes it was the converter, When I was there I also had him put on a dual exhaust system. The truck has plenty of power now. When I got home I just had to test it out by hooking up our camper trailer (34'). It was like being in heaven and on earth at the same time. It also made a hugh difference on the shifting of the transmission. Thank alot guy's things are now great. :icesangel

Sweet....

Did you have to pay for new converters or were they warrantied? Did you even use new converters?

The Converter Was Not Warrantied Because It Was The Original And The Pick-up Has About 148,000 Miles On It. But The Good Side Of Everything Is I Now Have Power And Better Gas Milage. YES I DID PUT ON A NEW CONVERTER BECAUSE OF THE 2 -O2 SENSORS

odd i think the noise it the cat. mine made the noise then went out clogged on the way to work . not good at all

I know a way to take the cat out and not trip any codes... basicaly the second O2 sensor looks for heat and more O2 then the first one. So i just welded a braket to srew the second O2 sensor to the out side of the exauhst pipe, it is like a little box for the sensor. Put 4000 miles on and have yet to trip a code, also improved my mpg alittle.