Forum Discussion

maxwell11's avatar
maxwell11
Explorer
Jan 01, 2016

Battery Load Tester

The motor on my 2005 Dodge diesel was not kicking over as fast as it had been the last few days.

got back from Christmas vacation and it would not start,

I disconnected each positive lead from the batteries and charged up each battery.
next day took it down to the auto parts store to get the batteries check as they were installed on October 2011.

Sales clerk disconnected one positive clamp, then using a Battery Load Tester checked both batteries, both batteries test bad under load.

so I bought new batteries. but got $60 rebate on the old ones.

however, after I got home I got to thinking,

even thought he showed me they failed on his "battery load test machine"

I really did not understand why they were still starting my truck after the battery recharge I gave them the night before, if they wre bad.

also, if one battery had gone bad, what was the likely hood, both batteries were bad???????????

however, if one was bad I was going to change both out for new batteries.

I am now thinking about buying me one of those Battery load test machines.

anyone else have one and use it,

was I taken in on the old bad battery load test trick, maybe I should have had him test these new batteries I bought on his machine, before I left the premises ??????

ah well, the old truck starts fine now with plenty of zip,
  • You might mention the brand of battery you replaced the OEM's with that failed in only what 4 years!! My OEM's lasted 7-8 years and still load tested fine, but I didn't want to chance it any longer with winter setting in. Rams are usually pretty easy on batteries so 4 years is a pretty short life IMO.
  • What was the ambient air temperature at each time?
    Did you have your engine heater on? Not sure what temperature Dodge says to turn it on at.
    I remember reading about some bad cables on the dual battery set up. I would test them.
    Most of the load tester are not able to go over 500 amp. Harbor Freight Sku 5911929 for example. Higher ones get expensive.
  • I think between you noticing the truck not turning over as fast and the no start condition, your batteries were on the way out.

    I also understand your skepticism of the load testers used at auto parts stores. I felt the same way when they said my battery was bad. While im sure their propietary machines err on the side of replacing the battery, I highly they are completely crooked.

    Batteries are not something to gamble with and you did well to replace both.
  • 4+ old batteries that failed the load test - The very best option is to replace both even if one had some life left.
  • rhagfo's avatar
    rhagfo
    Explorer III
    Well you did the right thing replacing both, if you only replace one the old one will pull the new one down faster.
    If the truck starts better, that is a great sign your batteries were bad. Mine were fine unless the truck sat several days, then were dead.