16' Bambi with a 4Runner?

[larry9000]

I've previously posted that the critical spec for the Toyota 4runner is the hitch rating. Though the 4R is rated at 5000# towing, Toyota assumes 10% hitch weight, or 500# max. Most trailers exceed 10% weight on the hitch, and are closer to 15%. For example, my 2006 16' Bambi is rated at 3500 GVWR with 430# hitch weight= 12.3%. But my real world measurement is 3500# and 500# hitch weight = 14.2%.

My 500# hitch weight of my 2016 4runner SR5 was right on the limit, and is certain to be over when loaded up or I add a second battery. So I went to a couple 4WD service shops in town to see what could be done. The first shop dismissed the 500# limit when using a WD hitch. He believed a true rating is much higher with WD, as the hitch weight is spread back to the axles of the TV and TT. However, he recommended that I go to the local Toyota-expertise shop to get another opinion. (There is no dealership nearby my mountain town of Steamboat Springs, but there is a shop that specializes in Toyotas). The owner of the shop came out and looked at my 4R. His verdict was that I had the factory Class 3 receiver on the vehicle, and should be good to go with weight distribution. Class 3 is rated at 600# weight carrying, and 1000# weight distribution. He also said the factory tow package includes a nice auxiliary transmission cooler, and there is no need to add an after market cooler. He said the one thing I could consider would be airbags to reduce the rear end sag (though it is limited already by the WD hitch).

I had previously contacted the Toyota rep and verified that the 2016 4runner was compatible with weight distributing hitches. Apparently there was a limit with previous generations of V6 4runners due to the bolt on crossmember holding the receiver. (The V8s had a hitch that bolted onto the frame rails directly, and had higher hitch ratings and even higher with WD hitches). In my 2016, the cross member is welded on as a continuation of the frame.

I also found some interesting insights on the internet. Apparently Toyota rates all SUV hitch weights as 10% of the towing capacity. RV 101 had an interesting article about Highlanders, and there were increases in hitch weight as the towing capacity increased with engine capacity, though there was no change in the chassis at all. This is further evidence that Toyota merely states 10% of towing capacity is the hitch weight limit, regardless of chassis and hitch design. In fact, my owner's manual states that the tongue weight should be between 9% and 11% of the trailer weight. 10% to 15% is considered the safe range in most literature.

Searching through the 4runner forums, I saw that earlier V8 4runners had a 750# tongue weight limit spec, but increased to 1095# with WD. That is not to say you can use those limits now, but if you add the 46% increase with WD to the current 500# weight carrying limit, you get 730 pounds.

My conclusion? If you have a 5th generation V6 4runner with a welded cross member to hold the receiver, you probably have more capacity than the 500# stated, particularly when you use a WD hitch. I'd recommend visually verifying that the cross member is welded in, as the bolt in members apparently had restrictions against WD hitches due to the torsional forces. This was true with 4th gen V6s, and may be true on early 5th gens too.