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Upgrades or replaces the converter section for 55-amp Parallax/Magnetek, WFCO, or Parallax RV power centers. Works with Parallax/Magnetek model 6355, WFCO model 8955, and Parallax models 7355, 7155, and 8355.
Features:
Specs:
Alternate Instructions
Customer Satisfaction Score:
94% were satisfied with this product
6% of customers were not satisfied
Ratings & Reviews
The PD product replaced the original Airstream (20 yrs old) Converter/charger. Install was fairly easy except the old 12 wires sizes did not fit into the new PCB clamps without a lot of force. Also, delivery was a day late even though I paid for rapid service (I live in downeast Maine - nothing comes on time). Powered up and it worked first try. Happy with PD's product!
It was an easy install. Replacing a 7155. Took pictures of where the wires go before to help with install. I had to remove it from its metal case to install it, just 4 screws in the bottom to remove it. I took a pic of the old unit to show
It is working great!
I called the etrailer on line # to make a change in my order for a converter. I explained the issue and Sienna took action to cancel my original order and place a new order. Sienna also took the time to verify exactly what was in my order. Once verified my order was immediately shipped and I received the right converter in two days
If I remember correctly one of your support technicians helped install it. That was very helpful and the unit has been working fine.
I purchased this replacement converter from etrailer.com to convert my travel trailer from lead acid to lithium batteries. Though I'm not an electrician, it was a fairly easy install with the help of the included instructions. The unit is easily changeable from FLA to lithium, and visa versa, simply by moving a little jumper on the board. I used it on several long Rv trips during the summer of 2025 and it worked perfectly. Also, many thanks to etrailer.com for steering me toward this part, away from a different part this I was originally looking at.
good product, poor installation manual on line
This was a direct replacement for the panel which came with the airstream but had the added feature of allowing me to charge Lithium Battery.
Easy to install and configure for lithium batteries. Only drawback is that the fuse board is difficult to snap into place and doesn't hold well.
I bought this so that I could charge a lithium battery instead of lead acid. Several years ago, I bought a PD4655 as an upgrade from a WFCO-8955PEC and it worked well, so I am hoping for the same result this time (although I wish there was just a simple upgrade fix as the parts are very similar between PD4655 and PD4655V, or at least a recycle option). The metal case has to be removed (4 small screws; likewise would be cool if there was a recycle option as I don't have a use for the case). You also have to move the jumper to the lithium side instead of the wizard side on the motherboard, but that's a simple lift and move of the jumper to one pin over. Just received today and look forward to a relatively straightforward install this weekend. Received a day earlier than expected, so happy with that too.
Charged my 300 aH LiPO4 battery like a champ and then appropriately dropped to trickle charge levels. Very satisfied.
Quick changeout, instructions took a bit to figure out the swap out but was a good fit once I figured it out.
Does what it says. Instructions didn't include a few details but overall a great product.
Install was straight forward, with good instructions. Charged batteries properly, e-trailer was great to deal with as they have been for all my purchase's.
I watched all videos I could find before attempting this job. After finishing I plug into 110 volt outlet my lithium battery was at 25% charge ( I had relocated the white cap over the lithium indicator as directed in video) my battery is blue tooth the green indicator light on the distribution panel was on no blinking. Battery showed 13.5 volts charging amps at 6.The battery is a 300ah showed that rate the 55 amp charger would take 94 hrs does this sound right?
Lazer S.
11/18/2025
Hi John! It sounds like you may need to switch the converter to Lithium mode. You should be seeing around 14.2 to 14.6 volts to actually charge the battery. The 13.5 would really only maintain the battery. Check out the link I have included as it will show the switch. What brand and model did you replace?
Helpful Links
Paid extra for fast shipping, and there was a problem on the shipping end. They did immediately ship again, once I brought it to their attention; however I was not offered the additional $10 back. The part itself works and was easy enough to install. Time will tell if it lasts.
I installed in my 2021 Winnebago Hike 171DB as part of Li battery conversion. Was able to complete in under an hour. Read directions and locate the wires first is my advice. Must take off outer metal case, then fits perfectly. Plugged in to shore power and trailer did not blow up. So far so good.
Charges my lithium battery fast. Bms shuts off charge when it gets too 100 percent.
This unit does not replace WFCO 8955 AD. The unit is too large. If you want to convert WFCO to lithium, Progressive Dynamics does not have an option despite what their description says. You will need WFCO 8955 AD MBA.
Easy install and charging AGM no problem. Installation took 40mins and that’s with with going meticulously slow when swapping wires over one at a time so I didn’t have to relabel everything. Have needed to replace the old converter for awhile now, wish I knew how uncomplicated the swap was sooner.
Communication from e-trailer was a series of stays updates and a check in after it was delivered. I really appreciated this. Last note, not necessarily all due to e-trailer, the package arrived two days earlier than expected. So good on USPS but also for e-trailer getting my package sent off within a day of clicking buy.
Very solid unit. Converter installation was straightforward. I couldn’t find anything on wiring for curcuit smart board after the battery and converter wires. Nothing on the 12 bottom lugs. There are 12 lugs and I had 9 wires. I went off the one pic in manual. It worked. I probably missed in the install instructions
This product works great in my RV after switching to lithium batteries. I read the directions thoroughly and watched lots of Youtube videos about installing a replacement power box. Installation was straight forward for this 67 year old female. If I had a question, I would call Progressive Dynamics. They were very helpful answering my particular questions.
I swapped out a Parallax 7155 unit from a 2017 Casita Spirit Deluxe and replaced it with this Progressive Dynamics PD4655V. The swap required removing two screws from the base of the old unit and I was able to slide it out of its plastic retainer tray. I removed the new Power Converter from its enclosure and was able to slide the new unit into the tray of the old unit. I was only able to use 1 of the 2 locking screws during reassembly. The unit is still very secure in the rack.
I used the new fuse board and replaced my old one. I had some trouble with a few wires reaching but managed to make it work.
After about 3 hours of work, I fired it up and saw it was charging my battery. After another 2 hours, I saw the voltage step down to a float charge and can see the 4 stage charger in action. Looks to be a solid product and I look forward to better battery life.
Thank you,
Mario
The converter unit arrived promptly and installation took about an hour following the online directions carefully. The tabs that held the other circuit board broke when I removed it, but was able to use a screw to attach new circuit board to a standoff where old board was. The new board had a hole in it that lined up perfectly with standoff. I’m now able to use 12v compressor fridge in camper while driving using Lifpo battery and battery charges quickly when plugged into 120v.
Hoping that the Progressive Dynamics converter will be a quality unit as the original WFCO was shortlived and the Powermax made it 4 years. The PD has dual fans compared to the others 1 fan for cooling. Installation in a wfco box is a bit challenging. 90 degree bends on the heavy gauge wires, had to run wire over the switch for battery type,and the cheap plastic wfco tabs that hold the fuse board break off easily. I originally rewired the new PD fuse panel from the bottom starting at #1 fuse but fuse #1,2 are offset to the left and low thus partially blocked by the cover making fuse changes near impossible. I only needed 10 circuits so I should have started wiring at #12 down to #2. Or maybe trim the plastic cover. There are 2 mounting holes in the PD fuse panel but they don't align with anything in my wfco box. The converter assembly fit perfectly. So far my 12v fuse panel is secured by the cover until I can configure a more secure mount. I turned on every light in the RV and barely heard some fan noise from the PD converter. Lead battery is charged at 13.16 volts and holding. I'd consider this easy but I've worked maintenance before.
Kate F.
4/23/2026
Sounds like you really put that install through its paces Randy! We’re hoping the Progressive Dynamics unit treats you better than the last two, and it’s great to hear it’s already running quiet and holding a steady charge. That dual fan setup seems to be doing its job. You also called out some very real challenges with fitting it into the WFCO box. Tight wire bends, fragile tabs, and misaligned mounting points can definitely turn a simple swap into a bit of a puzzle. Your notes about fuse positioning and wiring order are especially helpful for anyone tackling the same setup. Glad to hear you got it up and running, even if it took a little creativity along the way. Appreciate you sharing all the details.
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Victoria H.
3/14/2025
That's a clever and convenient idea, Sean! Thanks for sharing your insight, I know it will be a helpful tip to someone installing this in the future.