My understanding is that the selection of which WDH to buy, if any, should be based on your trailer's tongue weight
plus the weight
of cargo stowed behind the rear axle
. So, I "think" the 600-pound rating would be the closest match in our case.
came with an Eaz Lift w/ 1,000-pound bars so I have not used it as I think these bars are much too stiff for our tongue weight.
The Eaz Lift drawbar assembly is indeed a heavy booger; just about 46 pounds without the spring bars attached. The bottom of the assembly would hang about 7-inches below the top of my receiver. The top of my receiver is only 14-inches above the ground, or 13-inches when the trailer is hitched. So, it would have somewhat limited ground clearance in my case. This is probably not an issue for your Tacoma.
Additional to the weight, there are greasy components involved. So, if you tend to hitch and unhitch a lot, these might be considerations.
My vehicle is rated at 440-pounds tongue weight and 4,400-pounds trailer weight. It only squats about an inch, as measured at the ball, when I hitch the trailer. I have been dithering about whether to get lighter springs for the Eaz Lift, trying a different WDH, or continuing without any weight distribution and just adding anti-sway. After reading the Andy Thomson article Carol linked, I am now going to give stronger consideration to just getting lighter springs.
My installation has two short sections of capped 3-inch square tubing welded outboard of the A-frame to maintain clearance from the dual propane
cylinders. That's something to consider if you also have two cylinders located there.
The Casita's A-frame is constructed of significantly heavier channel than many of the older FGRV frames I have seen. Casita
installs many WDHs at the factory when people pick up their trailer. So, I anticipate that the trailer's frame would handle a properly sized WHD just fine.
If you don't have any, you might consider adding anti-sway even if you find that you don't need weight distribution.