I am seeing more and more of 16' trailers these days with a 20" to 24" extension to the back end the extension was installed with a downward angle of about 31°,,,, #1 This adds 20"  to floor length,,, #2  Vehicles are far easier to load,,,  #3  ramps length can be half as long, (old people will like this),,,

  Comments?  

 AW Chit,,DIY,,,and here I thought all those New Design trailers were actually "New Design Trailers" but now you telling us they are in fact ,,,,,"Road Graders",,,??  Who knew,,,??,,,,

If YOU modify your trailer for length , you'll also have to remove,relocate and weld on the spring mounts back on. Be 100% SURE to get them all lined up within 1/16" of square and true, that way it'll tow GREAT !

Normally tandem axles are 1/2 way of the deck, so 16' deck, center of axles is 8' from either end.

When you add ,say 2', of 'dove tail' or 'beaver tail' to a 16' trailer, you need to move axles back to 9' , the new 'center'.

 Hey Jay I have seen several trailers like the one Steve just posted that have more trailer floor in front of the springs than evenly spaced,,,fact is,,,I followed one this PM trying to flag it down to get a pic,,,,the closer I got ,,,,the faster she drove,,,,,,,,!!!

ONE formula is .. for a 18 ft trailer deck, take half of that is 9 ft to the CENTER... then move the axles back 1 inch for every foot of trailer length ( so move back 18 inches)... so the PIVOT between the two axles would be 10.5 ft from the front of the deck .. and 7.5 ft from the rear..

The SECOND formula is... for a 18 ft deck , and about 4 ft of tongue, the TOTAL length from the BALL to the rear is "about " 22 ft ...... put the pivot between the two axles at 2/3 from the  BALL... or  1/3 from the BACK of the DECK... which would be 1/3 x 22 or 7.3 ft  

so using formulat 1 you put the axles 7 ft 6 inchs from the REAR...using formula 2 you put the axles 7 ft 4 inches from the REAR ..... this is the PIVOT PIN  between the front and rear axles springs..

hmm, one concern about 'just adding 2 feet' is the extra additional weight of material to join the extra 2 feet of frame and decking to the existing trailer. probably need 1' overlap for the 'fish plates', and do 'something' about new ramp supports ?

It might be better to just buy an 18' trailer than modify the 16' one ?

 Hey Steve,,,are my eyes playing tricks on me or are the axles on your trailer set way farther back than close to center of trailer,,,:??

My 16ft car hauler has a 2ft dovetail.  Yes, easy to load vehicles on, and it gets easier-  leave it unhitched, chock the tires.  Use ramps with no support legs (flat).  Drive a car on, the hitch tilts up, car comes up the dovetail, then back tires on, then the nose of trailer comes down, and car is on.

There's no reason to move the axles when adding a 2ft dovetail.  The 16ft deck is a 16ft deck.  The dovetail won't normally carry any additional weight, the center of gravity of the load is still located in perspective of a 16ft trailer deck.  Weight of that dovetail extension is insignificant in comparison to the loaded 16ft trailer.  You'll have a lighter tongue weight when empty, but if you're running empty, it won't matter.

Yes, the hitch ball rises anywhere from 4-6 feet.  A 16ft trailer doesn't accept a very big car... a 1976 Buick Electra 255 sedan with 455 is about the biggest I've ever put on, and the doors wouldn't clear the trailer fenders, so I had to climb out the window.  When allowing it to tilt, there's much lower likelyhood of high-centering a low-clearance vehicle when crossing the apex, and if the car is unable to climb on it's own, it's much easier to push or winch on.  Once the front wheels reach the centerline between axles, the nose comes back down slowly, because it is lifting the rear wheels and ramps UP.  It is, in effect, exactly the same as a tilt-loading trailer.

Wife and I just put a 2007 Honda CR-V on mine two nights ago... and while one would expect it to be 'small', it only had about an inch and a half on one side, and three inches on the other.  Sure seemed silly that it was that close, in comparison to the Buick... hard to believe it, the CRV is barely 1000lbs lighter.

That IS a nice trailer,,Steve,,guess the angle of the pic makes it look that way,,,BUT,,,,BUT,,I HAVE seen trailers with the majority of trailer floor mostly to the front of axles, and wondered why they were built that way,,,? I was following one here Sunday to get a pic but that lady was scaired of that Dude following her had something else on his mind,,,,?? Never did catch her,,,,!

If you are buying a trailer to haul a fixed load (like hay or wood), axle placement becomes more important. As DMiller said, axle placement is most important to stop a trailer from swaying when towing at highway speeds. Enough tongue weight is important, or you will be "white knuckling" when towing.

A little off topic here, but I have been towing tractors on trailers for over 50 years. I much prefer to back tractors on a trailer, then to drive it on, if possible (if I'm loading narrow front tractors side by side to get more tractors on, it isn't possible). Most of my experience is with deck-over trailers. When I am unloading, I have about 28' of height to deal with. It's a heck of a lot safer and easier to drive off (especially if it's wet) than to back off, when gravity is working against you.

Even when I load my zero-turn mower on my utility trailer, I prefer backing on and driving off.

Well,,Dave Kamp,, That right there was my train of thought,,since the dove tail will not carry any significant weight while loaded. I have a small scale to determine tongue weight by moving vehicle back & forth for best affect. I believe the Dove Tail addition was invented for old people that have to winch on a vehicle (by hand ) by themselves,,,,the Dove tail does that for them,,,,

ps; I ain't as brave as you in loadin one while unlatched down tho,,,

PSS; I have looked at several youtube videos and to a one,,none have mentioned "HOW MUCH"  are the dove tails lowered, SO I did stop and measure 2 that I caught up with and one was 4 1/2" the other was 4",,,? 

i inadvertently used my 2" ball on my 2 5/16 ball 20' tandem trailer.  Hauled my d17.  She loaded fine but shot off the ball when i unloaded!  Had to find a new set of undershorts afterward