Here's another idea.

Disconnect the negatives from BOTH batteries.

Using a test light - (NOT a voltmeter) go from a negative post on each battery to it's cable end.

If the light illuminates brightly - you have a drain on your batteries that should not be there.

IF THAT IS TRUE:

Connect them back, and take off the positive lead to your alternator.

Try the test light from the post on the alternator to the wire.

If it lights brightly again, you may have a set of blown diodes in the alternator, and you can pull it and have it checked at a parts house. Bad diodes will allow the batteries to constantly drain through the alternator, and the alt will not be capable of charging right.

 

Nope, not too early. my 05 batts went this past fall and I went with interstate mtp-65's (I think). They are wayyy stronger than stock and have great reviews on here. I have recon BU lights, 4 hella 500 drive lights, 750 watt stero, 400 watt inverter, dvds etc and I am good to go with the interstates.

 

good point adam, as of last year i installed all the electronics in my sig...nav system with 6.5" screen, rear hd rest tv's, alarm system, inverter, AND remote start...wondering if that had alot to do with the drain over the past year, and more importantly, how much more juice do i need with the new set of batts??

the motorcraft max is what i was planning on buying tommorow. Will that provide the juice needed for all my electronics etc?

the stock motorcraft batts in now, are only 750 cc amps, the max jumps to 950 cc amps, with that be sufficiant?

 

The motorcraft max will probably be fine, I really like the interstates, i was going with optima until I read the reviews on here. glad I did. I got the two interstates for $180 (the cost of one optima).

 

whats the cc amps of the intersates you bought? I had the marine versions in my boat and like them also...

 

The Interstate Mega-Tron Plus batteries are available in 850 CCA (Part Number MTP-65) and 750 CCA (Part Number MTP-27). Both have a 85 month pro-rated warranty. The Interstate site lists the price range of the MTP-65's at $125.95 to $150.95 and the MTP-27's at $113.95 to $135.95. Interstate's are good batteries and I have run them before, but this time around the dealer was more convenient and I have had good luck with Motorcraft batteries as well...

The Motorcraft Max batteries are available in 750 CCA (Part Number BXT65-750) and 850 CCA (Part Number BXT65-850) and have a slightly better warranty with 100 months pro-rated and 3 year replacement. I checked my recipt and I paid $115 ea. for the 750 CCA's...

With 2 batteries at 750 or 850 CCA you will be more then fine. You have to remember that all your stuff is really running off the alternator once the truck is running...

 

yeah my stock MC batts are 750 CCA...i thought the MC max Batts were 950 CCA?? either way its another 100 or so amps, i think it should be fine, and the warranty is better and the price is btwn $50-$80 cheaper,(then interstate with the same CCAs) so seems like a winner to me...Thanks guys.

 

I had the same issue with my truck fine when weather was warm got alittle cold out truck was dead replaced both batterys and the same thing happened realy pissing me off not startin so when i had the batterys tested guy at advance said the alternater was fine so i checked it with my volt meter was only kickin out 11.4 volts and i have 7inch screen big amp when i turned it up would drop to 10.8 so it was just killin the batterys i put the new alternater in and my truck never started so well if when its like 10 degrees out just my 2 cents

 

This is a good point...all the tv srns etc wer installed only lst year..... could have been slowly draining since then!

 

Ok bought dual Motorcaft Max batt, (850 ccamps) truck turns over like a champ! this morning it was 10*F and she cranked over like the enigizer bunny was humping her!

I got em for $109 a piece and installed them myself, (dealer wanted $25 a piece to install) took me all of 20 min, including vaccuming out the batt boxes cleaning terminals etc...Piece of cake.

Thanks for all the great advice...problem solved....Seeya on the next one :0