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piecesparts · 04-01-2006, 09:06 PM

Go with the 100 amp alternator AT The LEAST. I would even consider a 140 amp if available, especially if you are going to get some serious subs to go with your sound system. Do you have air conditioning in this truck? Think of all of the loads that could be on at one time, like windshield wipers, headlights, A/C, heater fan blowing high speed, stereo/amps, and the truck at a stop light---Idling.

Most alternators carry 35 amps at an idle speed. The rating on an alternator is at rpms above 1500 RPM. I am running a truck with stereo, and electric cooling fans, and with the headlights on it dimmed at the stoplights. I put an alternator on that is 140 amp at full charge and it carries 80 amps at and idle speed. Solved my problem.

04-01-2006, 09:06 PM	#3
piecesparts Parts and more parts Join Date: Nov 2003 Location: Lebo, Kansas (middle of nowhere Posts: 6,821	Re: alternator question Go with the 100 amp alternator AT The LEAST. I would even consider a 140 amp if available, especially if you are going to get some serious subs to go with your sound system. Do you have air conditioning in this truck? Think of all of the loads that could be on at one time, like windshield wipers, headlights, A/C, heater fan blowing high speed, stereo/amps, and the truck at a stop light---Idling. Most alternators carry 35 amps at an idle speed. The rating on an alternator is at rpms above 1500 RPM. I am running a truck with stereo, and electric cooling fans, and with the headlights on it dimmed at the stoplights. I put an alternator on that is 140 amp at full charge and it carries 80 amps at and idle speed. Solved my problem. Last edited by piecesparts; 04-02-2006 at 12:15 AM.