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[Philipg]

seg

 

[DaveInDenver]

Can't think that's safe.

The rear frame cross member on a Cruiser is designed to accept a 4-bolt attachment and even that I think is marginal when the American definition of towing is applied. Toyota I very, very much doubt expected this.

What does the factory offer for that gen of Prado? I'd bet a bolt-on receiver.

I think the additional thing you may have to consider is that the cross member could be compromised from even it's original design criteria. Probably not too seriously but it wasn't like it was a design oversight by lacking those 8 holes. Not to mention the fatigue if it was used much.

 

[DaveInDenver]

Consider, too, that Cruisers Toyota imported, like 80s I know, had an option for a bolted on hitch even when they had the 4-bolt cross member. You have to spread the forces. Although a tire carrier isn't nearly as bad as a road train of a huge boat behind a camper.

There's some laws that cannot be disobeyed, such as the laws of physics. Body lifts didn't figure into the equation when the thing was on the drawing board, so it is what it is.

I'd consider fabricating something like you'd find with aftermarket hitches but without the drop.

Or an excuse to build a proper bumper. ;-)

 

[DaveInDenver]

There’s no drop on the bolt on hitch, they bolt flat to the bottom of the frame like so, but with a solid hitch the rear crossmember becomes kind of moot if it’s damaged, as the hitch is serving a similar function but much stronger

There is drop, insofar as the plates bolt to the underside of the frame and the cross member with the receiver is below those. If you make the frame plates longer so the crossing tube can sit on top instead the whole hitch is raised.

It wouldn't be a standard catalog item but the fabrication is reduced compared to a completely custom bumper. The ship sailed for a simple bolt-on solution when the body lift was installed.

Have you tried just flipping the one you show over? I'd guess the holes would line up but it wouldn't extend past the frame enough though.

With the right hitch you might find someone to cut and weld the receiver to the top of the hitch instead of the bottom and solve the problem, or fabricate one but I fear that will get very costly very fast

Exactly.

 

[Inukshuk]

In general that cross member is a rock-solid mounting location. The cross-member bolt on location is the towing location all over the world. I do not know why we do not use it in the USA.

The tow ball looks mostly like this:

The "D" value is (https://en.wikipedia.org/wiki/D-value_(transport))
a rating in kN that is typically attributed to mechanical couplings, and reflects dynamic loading limits between a towing vehicle and a trailer. The corresponding formula for a truck and trailer combination, used to determine the required D-value of a coupling, is:
T = Weight of towing vehicle including the vertical load on the fifth wheel
R = Total weight of the loaded trailer
U = Vertical load on the fifth wheel
g = Acceleration due to gravity (assumed to be 9.81 m/s 2 )

D (kN) = g x ((0.6 x T x R)/(T + R - U))[1]

17.5 kN can somewhat be expressed as 3,920 lbs towing capacity.

Will something bolted on an arm 48" above it on a 6" long arm rocking back on a 4x4 road hold or eventually break off? Probably. Its quite a bit of hammering torque. Probably never if only on pavement. It would be much better braced to the rear door. Then the hitch is only holding the vertical wight

 

[Inukshuk]

Of course, they are the Light-Duty Land Cruiser, badged as GX4x0 here.
Still, I am sure I have spent more time in and about Prado's than most.
You have concluded it is flimsy. I say its stout as hell. We booth agree its not designed for the application you intend and wisely you want to support it better. Always prudent.

 

[Corbet]

In general that cross member is a rock-solid mounting location. The cross-member bolt on location is the towing location all over the world. I do not know why we do not use it in the USA.

The tow ball looks mostly like this:
View attachment 116234

Hey as a moderator I feel I need to remind you this is a family friendly forum. And you should post photos accordingly.

 

[Basaltfj40]

@Burt88

 

[On the RX]

It is common to unbolt a particular aftermarket hitch for the 4runner from the frame mounts and flip the hitch for a larger departure angle and to cover the gap in a 2" body lift. Others have done as previously mentioned and cut off the box and welded to the top of the cross on the bolt on hitch.

 

[Lastresort576]

Another option....remove the body lift? they always seem to cause excess headaches.

 

[DaveInDenver]

In general that cross member is a rock-solid mounting location. The cross-member bolt on location is the towing location all over the world. I do not know why we do not use it in the USA.

We are in agreement 100% that this mounting location on a 40/60/80/100/200 LC (or Prado if the factory is in fact offering it) seems adequate for a ~4k lb (say class 1 or 2) tow point. Those pintle hooks you can mount there are usually at least 5 ton, so clearly a spot like this could be a substantial location. Does Toyota rate it in the manual or stamped on the cross member?

Just the same to meet SAE class 3 (8k max) Toyota offers a frame-mounted hitch instead even on Cruisers to reach the vehicle's towing limitation (which is generally about 5k, I think up until maybe the 100 and newer) and that probably can't be ignored.

None-the-less, isn't it apples to oranges? It looks like this truck's rear cross member was owner modified by drilling through it to accept the 4-bolt mount. Is that not the case? Did the Prado come with its rear cross member from the factory like that?

If it's not factory then without re-engineering the rear of the frame there's no safe way to do this, nevermind legally. The cross member was never deigned for a point load in the middle like that and that would need to be addressed.