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Round 7 to Flat 5 Trailer Adapter

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I have an adapter that goes from the round 7 connector on my Dodge to a flat 4 connector on my old boat. My new boat has brakes, so it has a flat 5 connector. Does anyone know where to find a one-piece round 7 to flat 5 adapter? If I have to, I can buy round 7 and flat 5 connectors and make one, but the other option is cleaner.

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99 2500 4x4, Quad Cab, 5 speed, Line-x bedliner, VA CPC, 9E Caribou camper (part of the time... ), Looking for BOMB Ideas... Just added K & N filter, working on Prime Loc & combo gauge...
 
If you do make one, cover the wires with split loom (aka convoluted tube) and tape the ends. Gives it an almost professional apperance.
 
I'm not sure about the flat 5 pin connector, as I have never seen one. But I had to find a round 7 to a round 5 for a race car trailer. My local trailer hitch place had the adapter in stock. Anyway, a place like that may have what you need as well. Find a hitch dealer in your area.
Craig

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2000, 2500,QC,4x4,white,tow,leather,6 spd,4. 10, 4" exhaust - turbo back, K&N, Balls of steel hitch, line-x bedliner, Autometer Ultralite pyro and boost... wouldn't dare add anything to void that good ole DC warranty!
 
I have seen all kinds of different adapters at the Walmart store here. Don't know if they have a flat 5. I have never seen one (or looked)either. You might want to check them out.
 
Same info as the others - Never seen a flat 5 but our local Bi-Mart has the 7 round to 4 flat and 6 round adapters and many trailer/hitch shops have them as well.
You might consider changing the boat end to the more popular 6 round ?.
 
U-haul doesn't have them; I already tried that. I've bought round 7 to flat 4 adapters from Walmart before, but again they don't have anything for flat 5. I think that all of the newer Dodge trucks with tow packages have the round 7 connectors, and most of the new boats with brakes (bass boats anyway)have the flat 5 connectors. I could wire the boat to round 7, but there are other boats with flat 5 connectors that I tow occasionally. I keep hoping that someone else out there already went through this and found one.

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99 2500 4x4, Quad Cab, 5 speed, Line-x bedliner, VA CPC, 9E Caribou camper (part of the time... ), Looking for BOMB Ideas... Just added K & N filter, working on Prime Loc & combo gauge...
 
Off the subject a tad but I got to thinking about them electric brakes on a boat trailer. Just curious how well they worked? I was always told not to mix electricity and water!

BTW - Another connector I have seen is a 5 pin round that is the same size as the 4 round. No adapters for that one yet.
 
I presume your trailer has hydraulic brakes with a surge actuator in the hitch assembly. If that is the case then the fifth wire in the “5-flat” is there to actuate a solenoid that closes on the brake line between the master cylinder [actuator] and the slave cylinders [brakes] when you are in reverse. This is done so you can back up a hill or over a curb, bump ,etc. Your “7-round to 4-flat” will work with the trailer just fine and all the lights will function as designed, you just won’t have this shut-off feature [ which a lot of us with surge brakes don’t have, and have to skid the tires to back up the driveway]. You can juryrig a separate lead to the fifth pin [which sticks out over the side of the 4 pin plug on the adapter] from the backup light circuit on your truck. That will allow you to use the “4-flat” adapter and be able to activate the solenoid when you shift into reverse.

I hope this helps.


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Roger Robinson, San Diego
2000 2500TD QC LB SLT [so far, still in warranty]
1963 Land Rover, Series II, original owner, hi-tech repair/overhaul kit includes adjustable spanner, pliers, & screw driver
 
Elken,
You might find what you are looking for at a large RV dealer. They usually have all sorts of electrical adapter and other towing supplies.
 
Another place you might try would be CT Farm and Country / Country General / Quality Farm & Country if there is one in your area. They used to have multiple adaptor connectors in stock or orderable. Alltho they have been sold twice since I worked there.

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95 Ram 2500 Auto Std Cab, Cat & Muffler Fell off, 125,000 miles.
Bombed-to-be!
 
I bought one for my boat trailer at the begining of this summer at NAPA. Looked around for the part # for you but couldn't find it. My local store had it right on the display,if yours' doesn't I'm sure they will order one.
 
I would dump the 5 flat connector for a more common trailer connector. Sure it's a great excuse not to let your friends and family borrow the boat #ad
but it would be a lot easier to wire it to a more standard plug, such as the 6 pole round.
 
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