I dont think a 1997 pickup has warranty issues to worry about. I would run the batteries in parallel to teach other and probably boost your alternator to WorkHorse standards like a 130-140 Amp model.

I have my Suburban running off two 12v batteries in parallel since I came back from the junkyard and got the left sided battery tray and battery cables from an older Sierra 1-ton. Both negatives go to the Engine block and you link the positives to each other with one running to the starter motor. 12v system but with two(of the same batteries) you double your reserve capacity and should always have enough current to turn the starter in the harshest weather. I have the 105 Amp alternator in it now, but I picked up 4 alternators at the junkyard so I ll test those soon and we will see whats what.

 

i think theres a new battery and alternator in order. im looking for an alternator thatll push around 120amps at rmp. does anybody know a good website for alternators?
i want 120 because i was told that stock is around 60. is this true?

 

60 amps was stock in the early 80s. Nothing leaves the factory less than 90 Amps these days. You probably have either a 90 or a 105 Amp alternator for a 1997.

 

ok. thank you

 

sorry to hijack the thread, i have a 99 burb and would like to add the second battery for those cold Canadian winters. appreciate any advise on wiring, of course neg goes to ground, but how to I tap in the pos? is there a special pigtail for this application? will the alt auto charge both? I know serial will produce 24v and that's a no no. just want to make sure I do the parallel install right the first time.

 

if you do a search on on this site or even google, you can find dozens of post on "how to" do this mod.

Eric

 

+ terminal from battery 1 to + terminal to battery 2.
- terminal from battery 2 to engine block.
- terminal from battery 1 to engine block.

= parallel setup.

alternator will charge them both equally IF the batteries are both in an excellent state of charge. If no,t the weaker battery usurps most of the alternator output, neglecting the better battery and therefore making that battery weak, so make sure your batteries are in great shape also.