I do quite a bit of towing with my K3500, and I'm just not satisfied with how it performs going up moderate and steep grades. I've had this truck since new and don't really want to sell without exploring options to improve towing performance. Anyone out there have experience and recommendations to explore? Thanks

 

What engine size, auto or manual transmission, single or dual rear axle?

About how much weight do you normally pull?

 

2000 K3500, 454 290hp, 410 ft. lbs, 4l80e Auto trans, 4WD, G80 positraction, GTS 4.10 rear end, 1 ton dually, Crew Cab, longbed. Towing truck bed camper 1500lbs, boat and tandem axle trailer 3500lbs.

 

Granted the 4L80’s weren’t great for towing, but 5000 pounds isn’t much of a load for a 1 ton - what is it doing that concerns you? Excessive power/speed loss? Has it always been that way or is it a more recent issue?

Do you live in an area of higher elevation?

Are you sure the brakes (particularly the parking brake) aren’t dragging?

Has the fuel system undergone any service that you’re aware of? Pump/regulator replacement, new injectors, etc? If not, you can check the fuel pressure to see if it’s meeting demand while driving. I don’t have the exact numbers on hand but IIRC there should be 55-62 PSI and it should maintain that while driving and through all engine speeds and loads.

If it doesn’t reach that pressure, or the pressure drops off under load, try blocking off the fuel return line and recheck - if it’s now good, the FPR needs replaced. If not, the pump is suspect.

One thing to consider is swapping in a manual transmission to eliminate power loss in the torque converter, but that will also require reprogramming the ECM to accommodate for it, which should be possible with a tuner. The NV3500 should be a straight swap in terms of bolting up, but the driveshaft may need to be modified to fit correctly.