2003 Chevy 2500 Very low power
January 29th, 2019, 8:32 PM
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2003 Chevy 2500 Very low power
03 Chevy 2500HD 217,000 miles
Engine 6.0L
Transmission 4L80e
The story on this truck is i picked up up after it had been sitting for 2 years with a bad transmission. When i first bought this truck it ran terrible and had constant P0300 codes, i ended up tracking this down to the injectors on cylinders 2 and 4 being plugged (im assuming from it sitting for 2 years), i replaced those and then it ran great. Then I replaced the transmission and torque converter with a used transmission out of a 00 chevy 2500 that appeared to be in great shape when i checked the magnet in the pan. After i got the transmission installed and I started driving the truck i noticed very quickly that it was a gutless wonder. It runs really well and at high RPM it accelerates quick but at low RPM's it has no power/torque. There is no check engine light on, every once and a while it pops on saying "knock sensor circuit low" but i reset it and it will stay off for a week or two. While i am driving it it sounds like it is working really hard all the time and has a hard time accelerating at all without downshifting and on normal highway driving while taking it easy i have only managed to get 10.5 mpg. It honestly feels like i have a trailer behind it with a pickup on it. The person i bought it from was using it to pull a trailer with excavation equipment on it (not a light load) and he never had power issues. I have searched for ideas on what to try, I have heard a lot of people saying to replace the catalytic converters which was my first guess also but when i was reading up on that it sounded like everyone with that issue was getting the random misfire code (flashing engine light) and i don't really want to just cut the Cats out to test it, and the owner before me didn't seem to have the low power issue. So other than that all i can think of is either the transmission or the torque converter. I am prepared to rebuild the transmission that was in this truck when i bought it and then get a new torque converter too but i don't really want to go through all the work unless i have information supporting this could be the problem. I have driven several of these trucks with around the same amount of miles and there is absolutely no comparison between these other trucks and my own.
What i really want to know is if the transmission and/or torque converter could cause such a significant power loss. and if not i want to know what else can without having misfire codes or anything.
Engine 6.0L
Transmission 4L80e
The story on this truck is i picked up up after it had been sitting for 2 years with a bad transmission. When i first bought this truck it ran terrible and had constant P0300 codes, i ended up tracking this down to the injectors on cylinders 2 and 4 being plugged (im assuming from it sitting for 2 years), i replaced those and then it ran great. Then I replaced the transmission and torque converter with a used transmission out of a 00 chevy 2500 that appeared to be in great shape when i checked the magnet in the pan. After i got the transmission installed and I started driving the truck i noticed very quickly that it was a gutless wonder. It runs really well and at high RPM it accelerates quick but at low RPM's it has no power/torque. There is no check engine light on, every once and a while it pops on saying "knock sensor circuit low" but i reset it and it will stay off for a week or two. While i am driving it it sounds like it is working really hard all the time and has a hard time accelerating at all without downshifting and on normal highway driving while taking it easy i have only managed to get 10.5 mpg. It honestly feels like i have a trailer behind it with a pickup on it. The person i bought it from was using it to pull a trailer with excavation equipment on it (not a light load) and he never had power issues. I have searched for ideas on what to try, I have heard a lot of people saying to replace the catalytic converters which was my first guess also but when i was reading up on that it sounded like everyone with that issue was getting the random misfire code (flashing engine light) and i don't really want to just cut the Cats out to test it, and the owner before me didn't seem to have the low power issue. So other than that all i can think of is either the transmission or the torque converter. I am prepared to rebuild the transmission that was in this truck when i bought it and then get a new torque converter too but i don't really want to go through all the work unless i have information supporting this could be the problem. I have driven several of these trucks with around the same amount of miles and there is absolutely no comparison between these other trucks and my own.
What i really want to know is if the transmission and/or torque converter could cause such a significant power loss. and if not i want to know what else can without having misfire codes or anything.
