Couple days ago I gave a couple guys a jump start accross the street from work. Was using the main battery on the drivers side. Ever since then my truck has been really slow cranking, like it's only cranking off of one battery. Sometimes it takes a good 10 seconds of sloooow cranking for it to fire. I figured maybe I had killed one of the batteries...so I hit them both with a multi-meter. 12.2v on both with motor off. 14.4 on both with motor running. I'm not real familar with diesel dual battery setups...What could have died? What am I missing? Is there some relay somewhere that melted down? Or did I just kill my battery(s) despite the multi-meter readings? It would be soooo goddamn typical of the last month if I had to buy two new batteries cause I gave someone a jump start....
I'd try hooking up a good battery charger to the main battery set on a higher power setting and see if that improves cranking speed. THen it might give you an idea if you are just not getting enough amperage from the batteries to the starter or if maybe the starter is on it's way out, or something making a bad connection from the battery to the starter. Maybe your connections from the main battery to the passenger side battery? Also maybe check your ground cables, I've had that happen due to a bad ground.
disconnect a battery then hit them with the volt meter. With no draw you won't see the voltage difference so you need to disconnect them.
Yup, dodge connects both batteries directly together so if your sticking a DMM on one battery your reading the voltage across both batteries, not the single.
As said above, check each disconnected. Last winter I used my truck to jump start all the semis that wouldn't start, and on that was gelled and had to leave my truck on there for about an hour to get enough to grank the fresh fuel in and such. Our Ford service truck would start to do the dead for us :doah:... Well, a month later my alt finally went out. I am guessing it is related to the draw I put on it. I wouldn't think just jumping another truck would hurt anything though.
I checked out all the cables/connections that I could easily see...couldn't get into it too much cause I was at work. Even looked at the one that goes directly from one battery to the other....I can't believe I didn't realize I was wasting my time trying to test them while they were wired together....duh.:doah: Good call on hookin up the battery charger on cranking assist. I suppose I could also take it to autozone and get one of the tards to roll out the electrical system tester thingy.... Man....I don't wanna buy new batteries....bleh Thanks for the replies.
Don't know if you have an Interstate battery store or not local but I get used batteries with a 30 day warranty for $20 a piece.
Depends, they are called "economy" batteries and they are all kinds of brands, not just interstate. They check them to make sure they are charged, check their water level, and clean them up. I have two in my pickup that I put in October of last year days after I bought the truck.(wasn't that nice that the dealership just charged the truck right before I got there instead of throwing some batteries in for me. ). I buy a ton of them for our farm equipment. I've probably bought 30-35 batteries in the last three years and have replaced maybe 4-5 of them since. I even have two, one in a tractor, and one in our '76 C30 that I put in 5 years ago. I use them mainly because most of our equipment sits 8-10months out of the year.
Oh and those wet cell batteries do a real FREAKIN nice job of rustin out the battery trays and causing havoc with the cruise control on a 12 valver.
