My beloved w123 has trouble in the cold (California cold, in the low 50's). Every morning is a gamble on if it will start or not, usually it takes at least a few cranks. I got a new battery yesterday, hoping this would do the trick. It didn't. The guy at Sears also tested the alternator and starter and said they are all fine. What do you guys think?

I'm tempted to also buy a Jump Box (AAA gets her running quickly with one of these) but I am not sure which ones will be able to handle the big Diesel battery. But, being a student, I don't want to spend too much if I don't have to.

Thoughts? Thanks !