Whats Latest Battery Advice?


Do you have an ammeter? A DVM category unit should work as long as you don't try to start the car. Disconnect the positive and put the DVM ammeter in and see how much current is being drawn. You could also take it to Autozone (the whole car) since I think their battery/charger health can read it but somehow they seem to do it without disconnecting terminals so I don't know how accurate it is... Check the spec on the DVM to see what current range it can tolerate and if it's good to say 5 or 10A it should be OK. If the parasites are pulling more than that you've got something that ought to be on switched power that isn't... Can you unplug your aftermarket alarm?
Good info, I will look into that. The alarm guts are under the car so I would have to take the trays off. I’ll revisit that next time they need to come off
 
Try replacing the BT Junior with a CTEK. The Junior is a low current model for motorcycle batteries. I've had no luck with Battery Tender, and never a problem with CTEK.
Is there a specific CTEK model you recommend?
 
Try replacing the BT Junior with a CTEK. The Junior is a low current model for motorcycle batteries. I've had no luck with Battery Tender, and never a problem with CTEK.
Agree with Howard, I use the CTEK for both my toys, never a problem!!!!
 
Use the AGM setting for our Absorbed Glass Mat batteries.

 
In 19 years I have had 3 Battery Tender Jrs. You can't really tell when they go bad. But they are cheap at Harbor Freight. I would replace it first for cheap before spending a bunch to run down some other gremlin.
 
One problem with multiple vehicles and RV's is battery maintenance. Many may disagree, but I have many Harbor Freight charger/maintainers spread around my house and shop. I have used these for years with excellent results. I use the basic charger/maintainer in the link below, they also have a deluxe version with permanent install battery leads. I also use their multi-meter to monitor battery charging by voltage and have many of these spread around my house and shop. I have higher quality meters (Fluke) and chargers, which sit on the shelf for the most part. The basic Harbor Freight charger/maintainer chargers at low amperage until it reaches about 14.0 volts, then it maintains at about 13.6 volts, perfect. This is the same charger that Ford supplied with the Ford GT's, a simple transformer and rectifier. The Harbor Freight maintainers have logic to limit amperage to maintain voltage at 13.6V, not sure if the Ford supplied charger does that??



 
Last edited:
Both of those tenders you linked are 12V and the Jr. is 6V. Maybe it is a matter or the Jr. being too wimpy for my car at least. Im going to try the CTEK and hope it holds. $100 is ok with me if my car will start when I need it to.
 
  • Like
Reactions: white out
I have been disappointed by several cheap tenders over the years. I have been using eight CTEK tenders for several years, and all my toys are happy!!
 
Both of those tenders you linked are 12V and the Jr. is 6V. Maybe it is a matter or the Jr. being too wimpy for my car at least. Im going to try the CTEK and hope it holds. $100 is ok with me if my car will start when I need it to.
I think CTEK makes good chargers. I do, however, still think highly of the Battery Tender Jr. You DO need to make sure to purchase the 12v version. The Jr is advertised at a maximum current of .75A with a 5-year warranty whereas the HF models are .5A with a 90-day warranty. FYI - the GT OEM charger is a "dumb" charger - it doesn't float on and off with battery voltage. Like many other, I have used the Battery Tenders for years with very good results.
 
Is there a specific CTEK model you recommend?

I have 20 of these, can be wired in with ring terminals or alligator clipped in an exposed battery application. Also has a “reconditioning” mode. They have been great for our vehicles.
 

I have 20 of these, can be wired in with ring terminals or alligator clipped in an exposed battery application. Also has a “reconditioning” mode. They have been great for our vehicles.

I purchased one and it has been delivered. Now I need to remove the battery get it charged and hook everything up. I will report back after it being on the CTEK but it may be a while since it’s the middle of winter here and Im not very excited to do the whole battery swap thing yet again..
 

I have 20 of these, can be wired in with ring terminals or alligator clipped in an exposed battery application. Also has a “reconditioning” mode. They have been great for our vehicles.
Yep, this is what I use on my Diablo Roadster.....happy with it although I had a battery sulfide itself to death in less than 18 months.

Still use an old Die Hard branded charger on the FGT that the previous owner gave me. That thing is probably 10 years old and still doing a good job.
 
I purchased one and it has been delivered. Now I need to remove the battery get it charged and hook everything up. I will report back after it being on the CTEK but it may be a while since it’s the middle of winter here and Im not very excited to do the whole battery swap thing yet again..
Why do you need to remove the battery to charge it? I charge mine in the car.
 
Why do you need to remove the battery to charge it? I charge mine in the car.
I don’t own a charger. It was also my understanding that our batteries need a slow charging process. I just bring it to Autozone, hopefully after this I won’t have to do anything besides keep it on the tender.
 
Your new Ctek will regenerate the battery, don’t have to take it to autozone
 
I don’t own a charger. It was also my understanding that our batteries need a slow charging process. I just bring it to Autozone, hopefully after this I won’t have to do anything besides keep it on the tender.
Hell, I charge mine in the car through the cigar lighter socket. 90Kmi, and I'm not meticulous about keeping the charger plugged in. No problems. I got 16 years out of my original battery.
 
Yep, this is what I use on my Diablo Roadster.....happy with it although I had a battery sulfide itself to death in less than 18 months.

Still use an old Die Hard branded charger on the FGT that the previous owner gave me. That thing is probably 10 years old and still doing a good job.
If your battery plates actually were sulfated, that's usually caused by sitting in a low charge state for an extended period. Sitting in a totally discharged state will sulfate them quickly.
 
If your battery plates actually were sulfated, that's usually caused by sitting in a low charge state for an extended period. Sitting in a totally discharged state will sulfate them quickly.
But that wasn't true in my case, running the tender is like a religion for me.
 
No problems. I got 16 years out of my original battery.

But the original batteries were a different animal altogether
.
 
  • Like
Reactions: Nafod
Yes, they were high quality internal construction, not like the cheapened versions that carry the same name today. Nevertheless, 16 years is extraordinary for a lead acid battery.