Engine/Transmission (1994 - 1998) No power towing on the hills

[Nick H]

Well I talked my brother into buying a dodge cummins but now there is a problem. It is a 98 12v 2500 4x4 auto. He recently bought a 7000# 5 wheel and while on the highway when he comes to a incline even a small one it slows down from sixty mph to fifty mph with the petal to the floor and will not give any more. Is this normal or is there something we could look at. We change the fuel filter, air cleaner, adjusted the valves and checked for air leaks. Any help would be appreciated. Thanks in advance.

 

[JNailor]

I would check the linkage on the injection pump to make sure you are getting full power

when the pedal is floored.

Dana

 

[Tom C]

That does not sound right... My last Dodge had an auto and 3. 54 gears, 4x4 and the auto definitly sucks up the power but I never had that much of a power loss. Mine would run 60mph with a 8500 lb load. That was up a 2% incline. I put in some injectors, a fueling box and transmission mods. then it would pull real good. But then the transmission started to slip and then it got wrecked and then... ... so its gone and im back to a 5 spd. It should pull a 7K load at 60 with ease, even with 3. 54 gears. Might check brake tension. tire pressure (truck & trailer), and how much wind resistance does the truck and 5er have (ei: visor, 13' tall 5er, etc). I keep 55psi in the front tires and 60 in the rear. My tire cold ratings are 80 psi but I think that would be a little hard, although they would roll easy with that much pressure.

 

[Deezul1]

When mine did that it was a bad overflow valve. About $55 from Piers

 

[dalton4]

Fuel pressure should be checked. Low pressure caused by a dirty filter, failing lift pump or weak overflow valve can cause the problem you stated. I was having the same problem at about 70k miles and it was the lift pump.



Jerry

 

[fortunate1]

Guages? What's the boost on that hill with that 5'r in tow? Also, what's the EGT? If the EGT doesn't go up accordingly, then fuel supply may not be sufficient. Remember Joe Donnelly: "Air + Fuel = Power". If power is low, then air and/or fuel is also low.



Timing? I had mine advanced to 15. 5, and that made a difference in power, milage, and EGT - all to the good. However, it was even more of a difference than it should have been. The stock timing (12. 5) had slipped to 10. 5, so instead of gaining 3 degrees I needed 5 more to get to where I wanted.



I think that checking the "throttle" linkage is also a good idea. Your friend may not be getting wide open even with the pedal on the floor.