Batteries moved by previous owner-should I move them back under the bed?

lkc001

Hello!   My new to me 2018 Tab 400 previous owner for some reason moved his battery (bigger than original battery) up to the tongue.  I am having an RV tech mount a truck tool box on the tongue and probably going down to one (1) propane bottle.  I have two (2) newer 12 volt deep cycle batteries that I'm moving from my old trailer to this Tab 400.

Would it really affect the towing experience (i.e. stability, sway, etc) if I moved the battery back under the bed where it was originally from the manufacturer plus adding an additional battery under the bed or no?  I know the 2018 Tab 400 has the heavier tongue weight--would it help or make any difference in the towing if I moved weight off the tongue?

My old trailer is the Tab 320S and I tow with a 2016 Nissan Frontier 4x4 with tow package and air bags.  The 320S towed like a dream--no bouncing, or sway, ever,  as long as I towed with weight in the back of the truck and full water tank.  Opinions?

Grumpy_G

IIRC the early 400s had a lot of tongue weight which was corrected in the 2021&up models. Moving the batteries to the tongue is only making it worse, so I would move them back.

lkc001

Grumpy_G said:

IIRC the early 400s had a lot of tongue weight which was corrected in the 2021&up models. Moving the batteries to the tongue is only making it worse, so I would move them back.

Thank you for the response!

SLJ

The previous owner might have had lithium batteries inside. Led acid batteries need outside ventilation. He might have kept his lithium and dropped a lead acid battery back out in the front. If the inside battery compartment isn't well ventilated to the outside you should keep lead acid batteries out of it.

lkc001

SLJ said:

The previous owner might have had lithium batteries inside. Led acid batteries need outside ventilation. He might have kept his lithium and dropped a lead acid battery back out in the front. If the inside battery compartment isn't well ventilated to the outside you should keep lead acid batteries out of it.

No he did not have lithium batteries at any time.  He intentionally ran wiring from the back up to the tongue for the battery he put on the tongue 

pthomas745

You would just need to sort out the venting of the lead acid batteries in the trailer.  Since the original batteries in the 400's were all lead acid back there, I'm sure we can find how the originals were vented.  In the first series of the big AGM's (one large 225 amp hour battery) it was enclosed in a plastic box and vented from there. 

lkc001

pthomas745 said:

You would just need to sort out the venting of the lead acid batteries in the trailer.  Since the original batteries in the 400's were all lead acid back there, I'm sure we can find how the originals were vented.  In the first series of the big AGM's (one large 225 amp hour battery) it was enclosed in a plastic box and vented from there. 

Do you know how it was vented?  There are no openings or vent holes under the bed in that storage area in my trailer.  Does it make a difference if they are sealed no maintenance batteries?

pthomas745

I looked for photos earlier this afternoon.  The "giant" battery in the big plastic box had a vent through (I believe) the passenger side of the trailer.  The versions with the dual 6v batteries had them enclosed in a separate section under the bed with sort of a sealed top. I haven't been able to find a photo of a 2018 (yet) but this thread has photos of the type of venting I'm talking about.  One "seems" to be in the floor, and one seems to be vented toward the little space on the passenger side where the battery switch and Gloso breaker are.  Do any of these photos match up what you are seeing?  The photos here seem to be examples of a 2021, and I'm not sure they are even close. https://tab-rv.vanillacommunity.com/discussion/11992/2021-tab-400-battery-and-inverter-box-pics/p1

Edit: here is another discussion on the same subject that discusses the venting. https://tab-rv.vanillacommunity.com/discussion/12367/what-is-the-vent-under-the-t-b-400

Horigan

On my 2019 400 the black box vented in two places; one on the side of the trailer above and forward of the battery switch, and one below the black box.  I would think you would only need one, as I've seen in some cars with batteries in the trunk.  Could be a good time to convert to LiFEPO4 batteries...

tphaggerty

I would replace the AGM battery with lithium and put them back under the bed. I replaced the two original 6 volt AGM batteries with three 12 volt lithium batteries and love having the additional storage. Two lithium batteries have significantly more storage than a single AGM battery since you can run them to a lower state of charge. I did have to do some modifications to the battery box in order to fit the battery sideways. But to lithium batteries will fit in the same area that the two original AGM batteries fit.

my guess is that the original owner wanted the space under the bed for additional storage. 

lkc001

I completely agree with people going to lithium & wish I could afford to do that however I cannot at this time @tphaggerty @Horigan

lkc001

pthomas745 said:

I looked for photos earlier this afternoon.  The "giant" battery in the big plastic box had a vent through (I believe) the passenger side of the trailer.  The versions with the dual 6v batteries had them enclosed in a separate section under the bed with sort of a sealed top. I haven't been able to find a photo of a 2018 (yet) but this thread has photos of the type of venting I'm talking about.  One "seems" to be in the floor, and one seems to be vented toward the little space on the passenger side where the battery switch and Gloso breaker are.  Do any of these photos match up what you are seeing?  The photos here seem to be examples of a 2021, and I'm not sure they are even close. https://tab-rv.vanillacommunity.com/discussion/11992/2021-tab-400-battery-and-inverter-box-pics/p1

Edit: here is another discussion on the same subject that discusses the venting. https://tab-rv.vanillacommunity.com/discussion/12367/what-is-the-vent-under-the-t-b-400

Thanks for the links— I read through both—went & looked under bed inside & under trailer behind wheel— I see no vents like in the pics.  Have sent an email to Nucamp for some info on what they did to vent.  Hopefully will hear back soon.  Surely they did something for safety?? Will report back on what I hear from Nucamp.

lkc001

@pthomas745. To follow up —looking inside under the bed there are two small cutouts by the battery shutoff — both of those have wiring going down under the floor— I have no way of knowing if they are also “vents”.

pthomas745

@lkc001 sorry that I can't find a good photo or thread (another Google failure!) 

lkc001

pthomas745 said:

@lkc001 sorry that I can't find a good photo or thread (another Google failure!) 

Thank you for trying --  the info you did find was helpful for me to check for possible ventilation.  I have also tried to search using many different words & phrases -- it's hard sometimes to find things you are searching for 

rh5555

Does it make a difference if they are sealed no maintenance batteries?

Yes, it does.  AGM batteries do not require venting, and I'd guess that other sealed batteries are the same.  Venting was provided on my trailer in case the AGMs were switched out for regular lead acid batteries, not because it was needed.

lkc001

rh5555 said:

Does it make a difference if they are sealed no maintenance batteries?

Yes, it does.  AGM batteries do not require venting, and I'd guess that other sealed batteries are the same.  Venting was provided on my trailer in case the AGMs were switched out for regular lead acid batteries, not because it was needed.

Thank you so much for the explanation!  So I don’t need to be concerned about this as my batteries are sealed AGM no maintenance batteries.  

Have you been happy with your towing stability with your batteries under the bed?

qhumberd

The 2018 and my 2019 configuration re batteries and axle placement and tongue weight from factory should be very similar. In our 2019 with the 2 AGM batteries on the passenger side of the bed we have no towing issues with our Tundra.

lkc001

qhumberd said:

The 2018 and my 2019 configuration re batteries and axle placement and tongue weight from factory should be very similar. In our 2019 with the 2 AGM batteries on the passenger side of the bed we have no towing issues with our Tundra.

Thanks for the info!

lkc001

Hello--PSA---  This will provide some info for anyone else who may be looking for this information.  Below is the answer I received from Creed at Nucamp--he replied pretty quickly and is always professional and polite.  Although he states that there are several "iterations" there are no pics or specific info on what those "iterations" are or what I should look for as far as venting or not. 

In addition, the statement that I should take it to a "service center" is not an option.  The closest dealer/service center to me that deals in Nucamp trailers is Windish RV in Longmont.  They are one of the WORST dealers/service centers in Colorado, with many many many complaints of substandard service work, keeping owners RVs for months on end only to get substandard repairs, AND they actually have a recording on their service phone line that states that they are overwhelmed, short staffed and they do not service anyone who did not purchase from them and they do not even answer their phone.   Truly pathetic that they are a Nucamp dealer.  Nucamp should do better.  I wouldn't take a little red wagon to Windish for repair.  

Nucamp Response copied and pasted:

"It's possible that the vent went through the floor then. There were atleast 2 different deviations in the ventilation and battery box setup. It could have also been patched on the side if a bodyshop ever worked on the unit. 

I would recommend taking this to a service center to have technicians add a battery, battery box, distribution studs, and the appropriate ventilation to ensure safety."

Best Regards,

elbolillo

Lifepo4 batteries can be purchased at very competitive prices compared to AGM or lead acid batteries.  No venting required.

lkc001

elbolillo said:

Lifepo4 batteries can be purchased at very competitive prices compared to AGM or lead acid batteries.  No venting required.

Yes & they are expensive & not an option for me currently 

SLJ

A good quality 100AH lithium is under $300 now. It lasts ten years and has more power. Cheaper in the long run than any lead acid or AGM. Battleborns are nice but on the extreme high end of cost.

pthomas745

@lkc001 I finally found a thread with the picture I was hoping to find, with a quick explanation of the various changes that were made during those years.

This is the "original" single AGM setup.

lkc001

@pthomas745. Thanks so much!  Based on this information & what I have already found out -- my trailer is a 2017 before they started putting in venting & Nucamp apparently doesn't know when they did what given the "several iteration" statements from Creed at Nucamp. To