4 to 7 pin adapter ?

[Dan S]

I'm looking at a Toyota Tundra with a 4 pin plug. Can these easily be changed out with an adapter? Or, does it require a run up to the truck battery to enable the trailer battery to charge while towing?

Thanks,

Dan

[TomW]

You will need to run three wires to match the functionality of a seven-pin outlet: Brakes, Charge, and Backup lights.

The brake wire (to a controller) is, IMO, the most important one of the three.

Tom

[GreatPumpkin]

The adaptor would allow you to use the lights on your trailer, but would not work for charging or braking or backup lights.

[moosetags]

You can't adapt 4 to seven without loosing functions. If you rewire, I would suggest a whole new seven wire harness. It would be easier than trying to retrofit. You can adapt a 7 back to a four if needed.

[Dan S]

So......I would tell the Toyota Dealer who is selling the Tundra to install the new harness and, since I have a Prodigy controller new in the box, to install it all at the same time.

How much is it for a typical harness and install? I want to be prepared when they say" Whoa, that will cost you $xx.xx


Thanks,

Dan

[CanoeStream]

Hi Dan -- Guess I'm surprised they made any Tundras without a 7-pin connector. One of your big questions should be if there's a pigtail plug-in under the dash somewhere (pigtail is the brake controller connector).

Here's some of the parts: Buy All of Your Trailer Parts and Accessories at RJay's Speed Shop!

People have talked about hooking up the brakes -- I should add it would be illegal to tow without brakes (most states if trailer is over 2000#).

[Jim Clark]

You may want to ask what class the hitch is. The heavier hitches normally have a 7 pin plug.

Jim

[Dan S]

Bob,

I have that question into them (pigtail). If it does not, the deal is a no-go as any trailer I get will be at least 20 feet.

Dan

[TomW]

Go with what Jim Clark said first. Between hitch replacement & wiring upgrades you may want to look at a different tow vehicle.

Tom

[Dan S]

That is bizarre that it does not have a 7 pin.....I'll call the dealership....which I hate doing. ...."So, what's it going to take to get you to drive this home today?"....shoot me.

[TomW]

Originally Posted by Dan S

That is bizarre that it does not have a 7 pin ...

Not really. There is no sense in including the wiring if your hitch can not accomodate the load. Class I & Class II (and maybe Class III?) hitches can not tow anything that has a 7 pin connector.

You need to make sure your hitch is rated for towing a heavy load.

Tom

[ljmiii]

Originally Posted by Dan S

I have that question into them (pigtail). If it does not, the deal is a no-go as any trailer I get will be at least 20 feet....

That is bizarre that it does not have a 7 pin.....I'll call the dealership....which I hate doing. ...."So, what's it going to take to get you to drive this home today?"....shoot me.

You don't say if the Tundra or Airstream you are looking at is a new one or not. If it is a 2007 then the only ones that don't come with a 7 pin standard are the 4.0L V6s. The max tow capacity of the V6s is 5000 or 5100lbs (long or standard bed).

The new 20' Safari's GVWR is 5000lbs and the 22' is 5600lbs. You need to look at the 4.7L V8 Tundra (max tow capacity 8100-8500lbs) if you want to tow these Airstreams.

If you are looking at older vehicles, then the above may not apply. Pre-2003 Tundras were commonly equipped with 4-pin connectors and older Airstreams weighted substantially less.

enjoy,
leo

[Dan S]

I'm looking at 2002-2005 Tundras. Most have the seven pin . However, the once vehicle that looked good has the four. I guess I could "make" the dealer install the class 4 hitch and harnes....

The trailers I'm considering are 20 foot Argosys or an older Airstream like a 17 Caravel.

Dan

[TomW]

Originally Posted by Dan S

.. I guess I could "make" the dealer install the class 4 hitch and harnes...

Like you said, ...."So, what's it going to take to get you to drive this home today?"....

Tom

[Jim Clark]

Another thing to think about is that a towing package is made up of much more than just the hitch such as larger radiator, alternator, bigger battery, supension tweaks, so be sure you know what you are getting. I always buy the factory towing package, even for my wife's SUV.

Thanks

Jim

[TomW]

Originally Posted by Jim Clark

... I always buy the factory towing package, even for my wife's SUV.

Since I have already extended private karma for an earlier post in this thread, please allow me to say publicly that "great minds think alike"

Tom

[Jim Clark]

Now if I could get the wife to buy into that statment.

Thanks Jim

[Dan S]

Again, I agree with what everyone is saying. I too feel a factory installed tow package would be better than someone simply bolting on a hitch. Most of the used Tacomas (as opposed to the Tundras) have a V6 and they call out an additional oil and transmission cooler. I also believe they have larger aternators...?

Dan

[ljmiii]

Originally Posted by Dan S

I'm looking at 2002-2005 Tundras. Most have the seven pin. However, the one vehicle that looked good has the four. I guess I could "make" the dealer install the class 4 hitch and harness....

Fair enough. My Toyota Highlander Hybrid came with a 4-pin stub that I needed to be converted into a 7-pin harness. I dropped off my HiHy, a Prodigy brake controller, a Draw-tire 4-pin stub to 4-pin harness adapter, a 4 to 7 pin harness adapter, and a Class III hitch off at a trailer shop and they put it all together for about $300. Your installation should be a little cheaper since I think the Tundra has a brake pigtail connector and the HiHy doesn't (they had to connect to my brake wires).

By the way, etrailer.com has three Class III receiver hitches for a 2004 Tundra and (with a weight distribution hitch) they range from 7,500-10,000lbs max tow capacity.

enjoy,
leo

[ljmiii]

All that said...I strongly agree with the other posters. Unless the dealer is offering you a truly amazing price, let the 4-pin truck go to someone who doesn't intend to do any towing.