My old battery has been real sluggish trying to start the diesel lately. Once it starts to cool off, I know it wont cut it. It has served pretty well so far even though many said it wasn't big enough for the Cummins. I think I bought this battery new 3 years ago when I fist finished the engine swap. The original battery had been out and uncharged for 7 months and just wasnt cutting it. The 690 CCA of the OEM sized battery was good all the way down to about 35 degrees. Below that it would struggle getting things cranked.
I think I finally did it in about a month ago when I dropped a wrench on top of the starter. It fell just in the right spot to arc straight from the terminal to the frame. It took me about a minute to frantically rip the hot terminal off of the battery. The wrench didn't weld itself to anything but it was hot as hell.
I wanted to avoid the complexity of a dual setup and just wanted the biggest one that would fit. I pulled the old battery tray out and measured up. Both a group 27 or 31 had the same depth front to back and were about an inch taller. The group 27 was 12" wide vs the stock 9" and the group 31 13" wide. The group 31 gave an additional 125 CCA cranking ability so I set out to find one.
I had my eye on a commercial/heavy duty exide but opted for an AGM marine battery I found at Academy for about twice as much. Hopefully it will turn out to be a good investment.
Here is the new battery next to the stocker
I had to lightly grind a small lip on the sheet metal below the tray and dropped it in. I flipped the battery around to put the terminals further to the rear to make sure hood clearance was good. There is plenty of cable slack.
I am using the factory strap and had to lengthen the holddown stud in the rear. Now that it fits I will make a tray frame from some light angle, tack that down and clean up the install. More pics to follow once I get that all in place.
I think I finally did it in about a month ago when I dropped a wrench on top of the starter. It fell just in the right spot to arc straight from the terminal to the frame. It took me about a minute to frantically rip the hot terminal off of the battery. The wrench didn't weld itself to anything but it was hot as hell.
I wanted to avoid the complexity of a dual setup and just wanted the biggest one that would fit. I pulled the old battery tray out and measured up. Both a group 27 or 31 had the same depth front to back and were about an inch taller. The group 27 was 12" wide vs the stock 9" and the group 31 13" wide. The group 31 gave an additional 125 CCA cranking ability so I set out to find one.
I had my eye on a commercial/heavy duty exide but opted for an AGM marine battery I found at Academy for about twice as much. Hopefully it will turn out to be a good investment.
Here is the new battery next to the stocker
I had to lightly grind a small lip on the sheet metal below the tray and dropped it in. I flipped the battery around to put the terminals further to the rear to make sure hood clearance was good. There is plenty of cable slack.
I am using the factory strap and had to lengthen the holddown stud in the rear. Now that it fits I will make a tray frame from some light angle, tack that down and clean up the install. More pics to follow once I get that all in place.
