Attention: TDR Forum Junkies 
If installed per the instructions, the only thing in the wheel-well should be the compressor. Trace the hose and wiring harness back from the compressor to the control module (should be on the firewall) and you should see the little (1.5"X1.5") black relay that just plugs in next to the rheostat that controls the pressure going to the cylinder. The rheostat will most likely have a number on the adjustment knob indicating the maximum pressure (65 psi on your truck) the system is to be operated at and all of this should be readably accessible for adjustment purposes.
The hose and wiring harness from the compressor are probably run behind the passenger-side battery and hard to see as they come up from the wheel-well. If unable to trace from that direction, follow the hot wire from the battery and it should lead to where the control module is located on the firewall. Unplug the black relay, which sits on top of a junction box about the same size and has four wires plugged into its' base, throw into the garbage, replace with one of the two relays you bought from NAPA, etc. and place the other relay in your glove box as a spare.
I suspect you have an air leak that is causing the relay to cycle too often, heat up, and cause the points to weld to each other. When operating correctly, the relay will activate causing the compressor to come on every 4 to 5 seconds maximum. If you have an air leak the relay will click like a metronome.
After replacing the relay, crank the engine when it is cold with the exhaust brake on. (The exhaust brake should activate until the engine reaches 160*.) Turn off the engine and immediately listen for any escaping air pressure. A good source for a leak is in the vicinity of the cylinder which is located directly behind the turbo, and these fittings get shaken pretty good on a regular basis. Retighten where the leak appears to be located, and check with a little soapy water. You should be ready to go!
- Ed
The hose and wiring harness from the compressor are probably run behind the passenger-side battery and hard to see as they come up from the wheel-well. If unable to trace from that direction, follow the hot wire from the battery and it should lead to where the control module is located on the firewall. Unplug the black relay, which sits on top of a junction box about the same size and has four wires plugged into its' base, throw into the garbage, replace with one of the two relays you bought from NAPA, etc. and place the other relay in your glove box as a spare.
I suspect you have an air leak that is causing the relay to cycle too often, heat up, and cause the points to weld to each other. When operating correctly, the relay will activate causing the compressor to come on every 4 to 5 seconds maximum. If you have an air leak the relay will click like a metronome.
After replacing the relay, crank the engine when it is cold with the exhaust brake on. (The exhaust brake should activate until the engine reaches 160*.) Turn off the engine and immediately listen for any escaping air pressure. A good source for a leak is in the vicinity of the cylinder which is located directly behind the turbo, and these fittings get shaken pretty good on a regular basis. Retighten where the leak appears to be located, and check with a little soapy water. You should be ready to go!
- Ed
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