This is kind of an odd question. I currently have motorcraft batteries in my 2003 Powerstroke and have been looking at them since it seems like they are not holding their reserve power very well. Like when I'm running the radio or other accesories and the engine is off. When I go to start the engine it has a hard time, once I had to get a jumpstart to get it started. I am curious though a couple months ago I had the batteries tested and the cold cranking amps were quite a bit above what they were rated for. They tested above 1000 CCA even though the batteries are only rated for around 800. Does anyone know if this is fine? Thanks for your help.

 

Since I have a 2003 as well, I'd like to see this answer.

How many miles do you have on yours? I'm up to 57K now on the originals.

Joe

 

Could be low on acid? Check the level and add some water if it's low. (Some people swear by distilled water, but I've always used tap water and never had a problem.)

 

I have an '06 with only 13000 miles and my motorcraft died already, they were also mismatched. 750 cca and 900 cca

 

Thanks for the replies. The batteries were actually low on water so I topped them off with distilled water. Ya haha I grew up always using distilled water for them so its habit. Also the truck has 220,000 miles on it *cough*cough* but hey if thats not proof that a 6.0L can last I dont know what is.

 

CCA varies with temperature. The colder it gets, the lower the CCA. Some batteries list the CCA at 32°F, others at 0°F. Some batteries even list both on their labels.

The desert is rough on batteries, and I go between the low and high desert (hot summers and freezing winters) so a set lasts me 3-4 years tops.

I've always added distilled water when needed, but then again the water here's hard as a rock. I don't want to chance adding that much calcium to the batteries.

 

Thanks for the reply, that might explain why the batteries have such a high reading on their CCAs. What bothers me is when I need a jump the truck act very dead, as in dash lights dim or flicker and the interior lights are very dim. Even though the truck may have been running just a couple hours ago. If anyone has any advice I am thinking that I may have something pulling too much power on startup. I am kind of curious to look at a power inverter that I have hooked in. But then Im not sure since this issue hardly happens unless I run accesories with the batteries off for awhile. Also the batteries tested at 12V when I needed the jumpstart. Thanks

 

My battary knowledge is somewhat dated as I haven't kept up. Lead acid battaries can put out a whallop of power in an instant, which is why they are used for starting engines. It is possibe for a battary to be able to supply small amounts of power for a long time but not be able to deliver enough to start an engine as this amount can be in the hundreds, obviously (see CCA). They could test ok but still not perform as needed. Looks like you have gotten your monies worth out of that set. Perhaps it is time for new ones. If you installed new equipment recently, is it draining your battaries when you leave the truck? The inverter you mentioned? Could you have a charging system problem, perhaps the battaries are not being charged properly. Most all of the factory systems that need a fair amount of power are disconnected during the start operation, so I don't think that is the situation. Unless you have additional devices you installed. I believe that the battaries are junk. Your last sentence leads me to this conclusion. This is why. A battary that reads normal then goes down upon loading is almost always bad, or minimally charged. Lead acid battaries can decieve you by showing 12V then that 12V disappears upon adding the load.

 

Thanks for the advice. Some further information I went ahead and had the battery voltage monitored on both batteries while starting the engine. Both batteries dropped to around 10.5 volts during the starting then climbed to around 14 volts. To the best of my knowledge around 10 volts is normal for starting the engine. As another basic step I went ahead and cleaned the battery terminals and cables due to some buildup on the terminal that was giving the voltmeter some trouble too. Currently there have been no starting problems, but does anyone have any advice on some of the major grounds that should be checked to make sure they are making good connection as well? Thanks.

 

Ten volts isn't bad, but it isn't good either, though mine only drop to 11-11.5 upon starting. Of course you are going to see 14 after the engine fires up. You are reading the output of the charging system then, not the same thing as what the battary will read after shutting of the engine if the battary won't take a charge. I was talking about readings in the 6-10v range. A battary can "look" charged then have nothing after attempting to use it. Cleaning the posts is critical to proper operation of the system. Corrosion can cause all kinds of headaches but is very easy to avoid with a little baking soda and water. Just follow the ground wires back to where they attach to the frame and the block. I would bet though that they are fine.

 

Thanks for the info. Yeah the only reason I had mentioned the 14 volts was simply for the info that I felt the alternator is probably okay. I will continue to see if there are any issues, I think the biggest thing that killed me was possibly having dirty battery terminals. Thanks for the help.

 

Have a similar problem here. Maybe someone knows what I should do.

I have an '03 with about 55k miles. It's wife's car she does car pool and we have a disabled 5 yr old daughter with a wheelchair so the truck is appreciated for that.

About three weeks ago, I noticed the truck beginning to get a little slower each day when starting up. I attributed it to the batteries. After a couple of days and one morning where it almost wouldn't turn over, I told wife to take it in to advanced auto where I had bought their "so called best" replacement batteries. they come with a 3 year warranty. The man was nice and told her, one battery did seem dead, the other was slightly lower, but probably been that way since its compensating for the dead one. he replaced the battery for her, and she watched him scrub off a little corrosion (I use those felt rings around the battery terminal posts) with a wire brush. The man told her, the other battery checked out to be fine though and that after this one was replaced, it should recharge the other one back to normal. The truck started fine and another week went by. I noticed though that it still wasn't starting as good as it normally did.
On Friday night after eating at my in-laws, the truck wouldn't start and all electrical lights/dash, etc. flickered on and off and the starter tried, but then everything died. I waited...and still nothing. We left the truck there, I came back the next day threw a battery charger on it but eventually needed to use the 50amp start button to start the truck. (I noticed a ton of corrosion around the negative terminal post and clamp) .i told wife to drive it back to advanced auto and find the man that helped her, so that he could change out the other battery. A different guy came out with his battery test stand to check the batteries. The first battery (one that hadn't been changed) he showed had voltage and was indicating a good battery on his machine. The new battery however he couldn't get a reading on, when touching it to the terminal clamp. When he touched it to the actual battery post the test machine showed battery good, but low charge. It also showed much more voltage than by touching the clamp alone. He also saw the corrosion and wiped some of it off, and sprayed some CRC battery terminal cleaner on it. ( I thought it weird to have so much corrosion on the new battery after only two weeks of being replaced). The corrosion was also only on the neg. not the pos. terminal. Well....the guy said go clean off the clamp as it was probably resisiting charge from the battery. I went home cleaned it some more and tried to start the truck our driveway and the same thing...everything died. My question is..what could this be? 1) could the terminal post clamp be so corroded to not conduct the charge and need replacement? i see a plastic sleeve with a bunch of wires leading off from that clamp to elsewhere in the truck. 2)could it be just one wire in that bunch? 3) alternator not charging the battery? 4) starter?
I used a digital voltmeter on the battery today after throwing a trickle charger on it to check the battery and when touching it to the pos. and the neg. terminal clamps I got like .8 volts, but when I touched the actual posts and not the clamps around the posts, I got 12 volts. Any suggestions? One of my friend's said if I take it to a Ford dealer they'll claim you need to replace everything and milk me for a couple of hundred bucks. Can I try replacing the wires and terminal clamp off that neg post or is it a hard job? I figure that might be the cheapest fix to try first.

 

Sounds like you need to replace the clamps. Starting an engine requires hundreds of amps. That much current will not flow through a corroded connection very easily. You will lose alot of voltage in the process across the connection. Your multimeter test is telling you that. Assuming you had it on the right scale! Your decimal could have been in the wrong place, but eight is too low anyways. This would also keep the battery from charging properly.

Normally, you want to replace both batteries at the same time. Everyone has different views on this, but it is true that one can drag the other down, depending on the configuration.

Try that first and see what happens.

 

Are you disconnecting one battery when testing? If not you could have one good battery and one weak one and when you test it pulls juice from both. Be sure to take cables off and test separately. I have an 03 with a 6.0 and just replaced mine. One was good the other tested bad, so I replaced them both with 1000 cca.

 

AND, as we all know, if you replace only one of your batteries, it's just a matter of days before the old battery kills both the new and the old! Always replace both at the same time!

Joe