Cl713

I have a 99 cl713 with 460 etech and 18 speed, and I too am continually dissapointed with power. I use the truck as a lowboy tractor, and very rarely gross over 90k and it is terrified of hills, the jake brake switch has to be off because it's impossible to shift with it on, and the transmission is tight so you have to be Johnny on the spot with every shift or you will be starting over. My old 3406b 400 will pull circles around this truck, and it has 1.2 million on the engine.

When I purchased my truck, the dealer told me that the truck originally was delivered with a mack 13 speed, and when the previous owner traded it in, the dealer changed the shifter effectively making it a 18 speed. After doing my research, I found that this is possible and not detrimental to the transmission, my question however; is there a modification or reprogramming that needs to take place with either the eecu or the vecu? Torque limiter? I am plagued with low power and I thought this might be related. The truck runs very strong in the lower gears, but seems to run out of power in high range with even a light load.

1999 cl 713

Etech 460

Heavy haul specs

You should have more turbo pressure. Have you checked the fins on intake and exhaust on the turbo? put a plug on the air charge cooler on the right side and put about 35 lbs of air pressure on the system and you can ck the cooler, intake manifold, and the tube at back of intake manifold that goes to the air compressor intake for leaks. If no leaks and no exhaust manifold gaskets leaking I would lean toward the turbo. Have you checked if it has a torque limit switch on the transmission, it could be bad. if you have one just unplug it and see what happens. I had a truck that was low on power but did not have the torque limit switch on the transmission but somebody had the transmission out and when they went back with it plugged the harness in to the air dryer harness. unplugged it and it was fine. You need more turbo pressure.

Where would I look for the torque limit switch.

Thanks guys! I'll check turbo and let you know what I find.

Hello all, I have a '99 cl with e7 etech 460. I seem to be plagued with low power, I have owned the truck for two years and it has never performed the way it should. I will start with what I know; no intake leaks, boost at 25-27lbs, no miss or rough running, not much black smoke, no fault codes. Now for the kicker, dyno test at 370hp, which is 80% of rated hp. I am told the 20% loss from flywheel to ground is acceptable. This truck is set up for heavy haul, 20k front and 46k rears, double frame, 18 speed, LOW rear end gears. I should have all the power I need to haul 80-85k loads and yet I'm passed by every truck on the road. Do I have a torque issue? Ecu issue? Is the turbo not spooling up fast enough to make the torque I need when I need it? Do I have fuel unit pump problems?

I'm stumped! And just about fed up! The mack dealer told me it's just my perception and that the truck is fine. I need help please!