Hello,
I have a 2003 chevy silverado with a 5.3 and I was looking to trade for a 2003 dodge quad cab cummins ho/auto 4x4. It has 25000 miles on it and it also has a curtis snowplow and 35x12.50x17 tires. I loved the truck other than the lack of power. It was absolutely depressing. In the same strech of road my truck will get 70mph, as will my friends dmax. The dodge only mustered 50mph. Do you think there was something wrong with it? It felt like it had decent power when the converter locked. It just accelerated really slowly. At highway speeds it took forever to get from 65-75. Granted this is with the plow and big tires but my old 7.3 would have out accelerated this thing... with a trailer. Help please b/c I like the truck and the deal is smokin!
Mike

 

First thing I would do is make sure that it is really an HO. The first 03's with auto's only came with the SO motor and the 47re tranny. I think it was Jan of 03 before they came out with the 48re and started putting the HO in the autos.

 

I looked at the sticker on the side of the engine, it says 305/555 on it. I work on heavy trucks, the first thing I do is read the sticker. I know these trucks are not supposed to accelerate like crazy but cmon... a decent running stock 94 cummins could have run with it.
Mike

 

Those size tires will affect performance. Especially if you have the 3.73 rear end.

 

I know they will affect it, but not this much. This thing was embarrasingly slow... If tires slow it down this much whats it gonna do with a 10000 lb trailer behind it.

 

If you think somethings wrong then I would walk away from the deal! There may be a reason it's such a good deal. As for my truck, it's got more power stock then my 98 had with the EZ box on it. The tires will definitely make it feel like you've lost some power though, especially if it's got 3:73s. Maybe the air filter is clogged! Mine got so dirty at about 12,000 miles that if I mashed the pedal the engine would bog down until I let up on the throttle. 03s are known for making the air filter filthy quickly. It could also be the fuel filter if it hasn't been changed. I change mine every 10,000 miles or so.
If it's just slow then just plug in a box and that problem will be solved.....

 

Just a guess, but it sounds like the torque converter is shot given the fact that it has a snow plow and good power seems to return when the converter is locked, taking the converter's fluid coupling out of the equation. Plows are very hard on a transmission, especially on a heavy truck like ours. Folks up here can go through a converter every two seasons plowing snow for side money if they don't take care of it. You generally don't see a plow on a big truck like ours just to plow the driveway. They are much too expensive for that. That guy was probably making some side money with it during the winter, suggesting it has been worked hard and the converter needs to be replaced. That may be why it was traded in and now sits on the dealer's used lot.

 

if its possible on an 03 did you do the key trick and check for codes.....you might have a bad map sensor or something

 

I think you guys are right, they had their "diesel tech" check it out and said thats how they are supposed to run. I drive a SO truck that had more power than this one. It did feel like there was excessive rpm/movement when the converter was unlocked so maybe they did fry it. Thanks for your responses, I'll keep looking for another truck. Also, when idling the truck stunk like oil, I thought it was engine but maybe transmission????

 

Dieselman, sounds like that HO was having problems. Mine is really pretty quick.

 

mine too, something doesn`t sound right