Tim9712v

Seems like all of the sudden (over night really) my batteries have become weak. Nothing has changed on the truck as far as electrical wise as far as i know. They seem sluggish and hard to start the truck. I cant imagine they are both going bad, they dont appear to old (bought truck used) I am going to get the batteries and charging system tested tommorrow... anything else it could be? Volt gauge shows right at 14v running and with key on assuming grid heaters are off. -Tim

crobtex

Both of my batteries went south at the same time........

Dr. Evil

Perhaps, is the temperature lower than its been in awhile?

You should always replace your batteries in pairs.

EDIT: just started the truck....looks like I need a set as well.

KATOOM

I bet you just lost one but you feel it in both. You might have an internal short in one which will cause the other to work even harder. If this has happened to you, it will put a strain on the charging system. Unhook both batteries from everything including each other and then check the voltage. It doesnt have to read nothing to be bad but probably will read less. It just doesnt do its part under a load. And yes to what Dr. Evil said, you should change both batteries when replacing them even if only one is no good.

Rattletrap1

One bad/weak battery will make both suffer as they will quickly equalize. Will also make the charging system suffer over time.

Best to replace in pairs, but need to test individually.

A starter going south will give same effect when starting.

Dieseldude4x4

The right battery usually goes bad first in the dual battery system and drags down the left battery. It happened on my 85 and my 99.

Tim9712v

I had the batteries "tested" today at the local autozone... I unhooked and we tested them individually and they both tested "good" and were reading 12+ vollt, with my volt meter with the truck off i too get an average of 13.7 or so between the 2 batteries.

Also had the charging system checked and it passed in good health.

I also took off all the cables and brushed down/sanded the connections (not particularly dirty. ) but this had no affect.

The symptoms seem exactly like a sluggish start due to a low battery, but cannot find any problems. Could it be the starter motor itself? Any input? -Tim

Rattletrap1

I'm assuming autozone load tested the batteries?

Check the leads to the starter...but yes...sounds like a starter...BTDT.

Prolly the best sure way to tell FOR SURE...is to attach an inductive ammeter to the starter lead when running the starter. Unfortunatley "amp clamps" of that range ain't cheap and I don't know what the specs are. On gassers you can pretty figure 1 amp per cubic inch.

You'll wanna get that fixed before it stops working altogether. I've had much better success by going to a rebuild house as opposed to autozone or equivalent for a new starter.

Sidewinder

I had the same symptoms, slow cranking with two "good" batteries. It was a combination of two things:

1. The end connector on the battery cable at the starter motor was badly corroded INSIDE the connector. I had to cut off about two inches of nasty cable off of the end and put on a new connector. I crimped and soldered the new one on.

2. The brushes inside the starter motor were almost worn out and not making good contact. If you do look at the starter motor check the solenoid contacts while your in there, they commonly get arced away.

The biggest difference for me came from fixing the cable. But after these changes it cranks great - even with the same batteries.

Dr. Evil

A simple voltage test with a multimeter doesnt really mean anything....the batteries have to be tied to a load to get an idea of the condition.

New HD starter contacts (and starters) can be had for cheap at:

http://www.fostertruck.com/dodge/

Dieseldude4x4

The actual load test will tell you what the batteries are doing, not just the volt check. They need to be load tested individually.

Tim9712v

Yes they were load tested individually... I was just saying i tested them with a volt meter....

If you had to pick between autozone- Duralast rebuilt starter $199 or an Advance Autolite Rebuilt starter for $193 both with lifetime warranties which would you pick? -Tim

Dr. Evil

LarryB's sell brand spankin new OEM starters for just a few bucks more:

http://www.fostertruck.com/dodge/

Valkyrie97

Don't waste your money at autozone or autolite. At the very least go to NAPA or Larry B's and get a good one if its bad. A rebuilder that works on trucks for a living is your best bet. The rebuilder down the hill from me has pulled that autozone trash out of the boxes in front of customers and showed them that what they have bought isn't rebuilt. I can't figure out how those people stay in business.

Dieseldude4x4

I don't buy anything from Auto Zone or Advance that doesn't come in a bottle or can. My son went through four alternators from Advance before he finally figured out to go to NAPA and get a good one.