20 Most Recent 2000 Chevrolet Silverado 2500 - Page 2 Questions & Answers

is battery good..do the lights stay on while attempting to start or do they go dead..

I once had this problem on a chevy and found the after market starter holes made the engagement too tight. Drilling larger holes solved the problem, allowing a little clearence between the gears when meshed.

Fuel pump in gas tank probably bad

try the thermostat first a.if this does not fix it yes probably the heater core .its behind the dash and at some point it should dump a lot of water probably in the passenger side floor board.

If the engine is reaching normal temp, and both heater hoses are hot, it could be a problem with the blend door under the dash.

If you are saying the engine will not crank but if it does the brake cable gets hot, it sounds like the engine is not grounded to the frame.

On the full size, the front actuator is electric, not vacuum.

When in 4wd mode, a switch on top of the transfer case conducts 12 volts out to the actuator. Wire #50 (brown) is the 12v feed, and it conducts to the light blue wire (#900) to the actuator.
When shifted out of 4wd, the switch opens up and no voltage goes to the actuator.

Check voltage at the connector for the front actuator (at the front differential - it looks like a large bullet that threads into the front diff.) If it has 12 volts, the actuator is the problem. If it does not have 12 volts, check the transfer case switch and the power feed to the transfer case.

I'll assume it is the actuator, if the plug to the actuator is getting 12 volts when in 4wd.
The way this actuator works, is it is a sealed chamber that gets heated by voltage. When it heats, the pin in the end swells and pushes a shift fork in the front differential. The shift fork engages a spline on the passenger side of the differential, and boom! you have 4WD.

GM offered an upgrade to this actuator that is a motor instead of a heated device. However, it requires a small harness addition, a spacer, and a new actuator. It is about a $150 to $200 option.

If I were you, I would buy a new heated actuator. They are available at most auto parts stores, and are about $90. They are also on eBay for about $55 plus shipping. These are very easy to change - just thread out the old one, and thread in a new one.

Good luck, That actuator is usually the problem 90% of time but check the fuse first in your fuse box.

The blend doors are controlled by small electric motors.One of the motors could have failed, or the blend door is sticking.

need more input to understand what you want to know

The accumulator or dryer looks like a long cylinder, it has a pressure switch on it and two wires attached to it. pull the wired molex off, with the ac set on max cooling, jump out the two wires with a wire or paperclip, if the clutch on the ac compressor engages, check the cab to see if its cooling, if it does cool the switch needs to be replaced, if it does not cool, you may need freon, and there could be a sign of a leak in your system, that can be best checked with ac manifold guages. the low pressure switch is there for safety if the canistor or accumulator is low or has no freon the switch opens up and keeps the clutch from running so that the compressor will not burn up. good luck!