over charging alternator

Except for battery charging and alternator dips, there should be negligible current flowing to/from the battery. But there should be no major voltage drops between alt body, engine, chassis & battery -ve. And the battery terminals and all contacts should be clean to ensure "clamping" of any spikes. Normally I wouldn't expect huge spikes from an alternator unless it has an external regulator (especially mechanical if such things still exist!), but these are large output alts with about 2 to 3 times normal capacities.

oldspark wrote: Except for battery charging and alternator dips, there should be negligible current flowing to/from the battery. But there should be no major voltage drops between alt body, engine, chassis & battery -ve. And the battery terminals and all contacts should be clean to ensure "clamping" of any spikes. Normally I wouldn't expect huge spikes from an alternator unless it has an external regulator (especially mechanical if such things still exist!), but these are large output alts with about 2 to 3 times normal capacities.

Yeah I just went to walmart and got a more efficient terminal for my battery. It was much needed anyway. But i hope this could be the reason. My battery is already charging better with the truck turned on. But i couldnt test it because its 4am in a apartment complex.I can't hear you!

Just my 2 cents. There are very few "frames,chassis" today. Almost everything is uni-body.What this means is poor welds,"goop" between the body parts ect. GM vehicles are the worst. The only thing to do in my opinion, is to ground EVERYTHING back to the battery.This can be a pain in some cases, but it eliminates a lot of those mysterious head scratchin',wrench throwin, dog kickin' problems. Not to memtion buying a lot of gadgets that don't work."That'll get ya 10 in Leavenworth,11 in Twelveworth, or 5 & 10 in Woolworth". Groucho Marx                                                      

MrArff - are you saying that modern vehicles are a collection of non-welded (electrically bonded) metal panels? I thought Uni-body & monocoque construction meant better electrical bonding - ie, NO insulation between body and chassis/frame (whether unintended corrosion or rubber/noise insulation etc). I also thought welds or fusion to still be the only feasible panel joining method (for most of the vehicle's construction).    I'm not saying that bonding isn't an issue. A common mistake for those with separate chassis and body was not bonding the two (ie, hi-power alternator and battery grounded to chassis with amps grounded to body with insufficient body/chassis connection). Similar bonding issues contribute to electrical noise - eg, bonnets needing a grounding strap etc. My reason for asking is that a few years back - in reply to someone's similar statement about a chassis/body - I commented that I found it incredible that panel work and welds etc would NOT exceed the conductivity of large cables, and if it did, I would be somewhat worried about the vehicle's structural integrity!! If your experience is different, I'd like to know more. (The older statement above was made by a reality-challenged graduate working in the industry.) I have often stated that a dedicated ground strap back to the alternator and (engine) battery may be worthwhile as it avoids cable/chassis connection breakdowns, but that such cables should not be required. (Better instead to duplicate cable bolts/joins to save weight & cost.) I use chassis as a generic term for body/chassis. (I tend to use earth or chassis, not "ground". I'd rather use 0V.) Whilst it does mean chassis for separate frame/body vehicles (trucks, bikes, my ute etc), it implies "chassis rails" in monocoque vehicles (as per all my sedans) - the latter mainly for physical reasons when bonding/bolting 4G, 0G etc panel sections. If that terminology is different on this site, I should know so I can avoid confusion.    Thanks in anticipation!