Since my truck is only getting occasional use, I'm really not getting normal battery life anymore. I've got a couple of battery tenders, but it seems like I will only sporadically hook them up. About 20 years ago, having the same issues on my boat, I went from a starting battery to a deep cycle battery and my issues were over. This is on a 502 ci (big) gas motor with just one battery. Do you guys think this would also work on a little used diesel? At very least, a deep cycle doesn't lose much life after being discharged. I would just do it but I really don't want to try a $200+ experiment if someone KNOWS this won't work. Thanks in advance.

 

I don't think the alternator puts out enough to charge two deep cycle batts. Golf cart charger puts out 15-20 amps to charge deep
cycle batts. I don't know what the trucks put out

 

Deep cycle batteries are not designed for starting (rapid discharge) so you may have issues getting started in cold weather. Pretty much a bandaid anyway; there's a drain in the electrical system. A better bandaid would be a battery cutoff switch, IMO. The vaccine would be diagnosing and repairing the drain.

 

I think you really need to hook up a battery tender of some sort. Maybe a quick connect plug would help you remember/feel motivated to plug it in more often.

 

As stated above, a deep cycle battery is not your answer. They do not do well delivering a bunch of amps all at once. Get an appropriately sized and rated battery for the application. Use the deep cycle for your trolling motor.

 

I don't use my truck all that often either. It's 17 years old, with only 60 something k miles. I had battery life issues with the first two sets of batteries... the OEMs, and the Motorcraft Super Duty replacements. While each set lasted about 4.5 years, the last two years of each set were a PITA, fraught with the need to jump start the truck all the time.

About seven years ago, I put an end to all that, with dual purpose deep cycle + starting combination batteries. I also added battery disconnects on the negative terminals. I think the better batteries are more responsible for the improvement than the disconnects, simply because I generally don't remember to disconnect the truck batteries unless I'm working on it (which is all too often), and then I disconnect them every time I open the hood, because quick disconnects make it so easy to do.

But the real PITA saver is a good pair of high quality AGM batteries. It isn't just that they have lasted with infrequent truck use over the last seven years. It is that I've never needed a jump start during that last seven years, whereas before, the lead acid starting batteries would start occasionally needing a jump after just two years in service.

A lot of guys report having to change batteries every 3 years. Average is every 5. Extraordinary is every 7. Well, I'm moving into year 8 with these AGMs, and now that I've made other charge system improvements, I'd like to see an even 10 years out of these batteries, which will easily make them well worth their $200+ price, given that the years were all good years, not wonky years, with a battery change cycle or two in between.

The vaccine that David talks about in my case is the factory OEM radio. It has a parasitic drain. It also doesn't work very well. I'm not putting an aftermarket radio in that invites thieves. And I don't listen to the radio all that much, so I just leave the stock radio in there for the clock. One day, I'll change it, but in the meantime, my AGM batteries don't seem to mind.

Here is a photo of the AGM batteries that are rated dual purpose, deep cycle and start. Sears doesn't sell them anymore, but the actual manufacturer of this battery still makes them under the Odyssey and Hawker (military version) name brands. Prices average around $250 each.


This photo also shows my version of David's "Band-Aid"...

 

I am not using MY truck much (on purpose) and just today I installed a maintainer velcro mounted to the top of the under hood fuse box, ran the cord/plug up front right by the block heater plug-its quite conveniant for me......its plugged in right now......

 

I believe the link below is to the battery that replaces the Die Hard that Y2KW57 has pictured above.

https://www.amazon.com/Odyssey-65-PC.../dp/B00249GW9S

 

Any battery that has a smart charger or maintainer connected when sitting for a while will have a long life. When a vehicle is shut off, the batteries start sulfating immediately until charged up again by either running the engine or connected to a charger. So if you only drive intermittently, you can save a lot of money in batteries by buying a maintainer.

Larry

 

I agree with Larry (I can't think of a time when I haven't agreed with Larry).

Here is my 8 stage smart charger (that also acts as a set and forget automatic battery maintainer, including pulsing to stir the chemistry up once in a while, as dictated by voltage drop and temperature):





This smart charger was one of the very few acceptable chargers that made the approved charger list issued by the battery manufacturer I use.

 

The batteries will fail if left alone for too long - connected, disconnected, stating, deep, or whatever. I'm a boat guy, so I always use twin deep cycle batteries on an Off, 1, 2, All make/break switch. I also use a battery tender. While the off switch on the truck is a good idea, the battery tender overrides the need for that.

I know my truck can sit through winter for three months and crank up - I've done it. I also know that our glow plugs draw a ton of power at the same time the engine needs to crank. On top of that, diesels work by very high compression without the aid of spark ignition - so that puts even more load on the starter. Your single battery for your 501 CI gas engine is no match for your tow vehicle.

A smart battery tender that is permanently installed and convenient to plug in would be my approach to the problem.

 

I recently fitted a pair of these bad boys, my truck starts so much easier. It was good before but occasionally when really cold (<32°f) it would need a couple of attempts. Now it spins the motor over like it has no compression & yesterday (34°f) I just jumped in & turned the key without waiting for the wts lamp to extinguish & it fired right up. I suppose it will be a while until I find out if the investment was worthwhile!

 

The Odyssey batteries can be "left alone" (disconnected) for up to two years without becoming discharged. It is one of the significant benefits that comes with the price.

Another significant benefit, regardless of how long the battery lasts, is how deeply it can be discharged... much more so than a liquid lead acid SLI (starting lighting ignition) battery.

And even if none of the energy storage features "float your boat"... ... the constantly clean, corrosion free battery tray, and more importantly, the clean, corrosion free battery terminals, will make you smile every time you open the hood. No white puffy powdery green crusty acidic terminal and cable destroying high resistance causing mess to have to add to the maintenance chores... along with the caustic cover ups. No more replacing battery cables (unless you just want to, to handle a higher amp alternator), no more removing, wire brushing, and repainting battery trays.

Even if AGM batteries performed exactly the same energy storage wise as liquid lead acid batteries... the benefits of not facing a hazmat site on either side of the radiator make AGMs worth it to me.

Speaking of hazards, AGMs are recombinant batteries, which practically eliminate the constant risk of explosive gasses igniting on a connection arc, an issue so prevalent with lead acid batteries that most OEMs instruct that jump start ground leads be connected to the block, not the battery, and GM and Toyota take it a step further by also providing a remote positive post away from the battery. Nice not to have to worry about stuff like that anymore.

Liquid lead acid batteries always outgass. That's why we need to check the water. Recombinant batteries reabsorb their own outgassing in the electrolytic mat... hence the name "Absorbed Glass Mat", or AGM. I realize most folks reading already know this. I'm just lobbing one out there for that rare reader who may not have had the chance to look that deeply into batteries yet.

My point is, I didn't have to wait until I found out if the investment was worthwhile. I found out right away. Living liquid lead acid free is liberating.

 

Alliteration... it's been a while.

I found this and felt compelled to share [LINK].

 

Speaking as someone who has had a battery literally explode when connecting I can tell you it's not a good experience, I was fortunate I was able to hose myself down immediately so only only sustained some cuts but I was so nearly blinded that I'm super cautious around freshly charged batteries.