Towing with a custom bumper? (1 Viewer)

[airsix]

I'm mapping out the plan for my recently acquired '96. This is not my first vehicle project, but it is my first "off-road build". One thing I want is the ability to do some towing on occasion but I see a lot of "not rated for towing" disclaimers when it comes to aftermarket receiver bumpers (and no safety chain points). Can anyone here educate me about this? If a guy wants to fab up a quality hitch arrangement what are the rules, standards, etc? I'm leaning toward doing a 4x4 labs kit and I'll be darned if that receiver is going to just be there for looks.

Thanks!

Ben

 

[86tuning]

How much are you towing? I drag my boat around with a hitch bolted to the rear crossmember.

The 80 has a towing capacity of 5000 lbs in USA but 3500kg (7800 lbs) overseas.

Those towing disclaimers IMO are exactly that. The designer has no intention of paying to test the unit, and in the case of a bumper kit, has no control over the weld quality.

That said, most of these bumpers are more sturdily built than many frame mounted receiver hitches.

 

[airsix]

Currently I will only be towing 2k-3k but like my options to be open. I know the 80 isn't the greatest tow-rig platform but I'd still like to maximize its utility.

Is tow capacity a DOT enforced thing, or manufacturer recommendation to keep people from ruining transmissions?

Ben

 

[Offroads4x4]

I only think the towing rate will be questioned is when the hitch failed and you caused the accident (Insurance company would try to shift blame to get out of a bigger claim) or it is more than obvious you are reaching or have exceeded your tow capacity by the looks of your load.

If you question your welding skills then get a local welding shop to go over your welds once your done building it and mount it for you. This would give you an out on liability as well (keep your shops bill/work order).

At 2-3K I don't think you would ever be questioned.

JM2C

 

[plutonius]

I've been talking to Luke at 4x4 about beefing up a tow hitch, and he suggested extending the receiver a bit and gussetting it on the underside, as (in the case of the 4x4 Labs bumper) the angle on the face of the bumper shell doesn't really allow for alot of tongue weight (say for hitch-mount carrying a motorcycle). It might not look quite as sleek as it could, but I'll take the function over form in this case. I can update with pics once my bumper is done, but here is the standard config:

 

[airsix]

Thanks for the responses, guys.

Ben

 

[IdahoDoug]

"That said, most of these bumpers are more sturdily built than many frame mounted receiver hitches. "

That deserves a comment that aftermarket bumpers are unlikely to ever reach the strength for towing of a common every day ordinary Class III hitch such as the factory one for the 80. Not even close. A Class III hitch has longitudinal runners along both frame members, and a truly massive cross member that is possibly stronger than the 80's frame is. Combined with multiple bolts through the frame, this creates a towing mount that meets the DOT's requirements.

While aftermarket rear bumpers are beautifully crafted and make use of multiple frame mounts as well, they generally don't place the massive structural emphasis on also being a dedicated Class III hitch mount - instead offering a receiver designed for light towing, or to carry a bike rack or similar. The center of the bumper would basically have to add as much steel as a Class III hitch and mount on all the frame points the Class III does using metal that thick - not thinner metal. I suspect this has to do with both cost and weight issues in designing a strong and capable offroad bumper that can take the heavy hits of serious offroad use - it would make the bumper cost more and weigh more even though perhaps only 5% of buyers want the Class III level of towing.

The Class III mount strategy also has to be extremely strong so that in a heavy rear crash the hitch will not fold and punch a hole in the fuel tank. They are tested specifically for this so the vehicle is as safe against fuel leakage with a hitch as it is without.

It's a serious commitment that bumper makers rightly avoid since most buyers don't need heavy tow capacity. But don't make the mistake thinking that the opposite is true - that a strong offroad bumper is also strong enough for the 80's full rated tow capacity.

DougM

 

[Tools R Us]

...
That deserves a comment that aftermarket bumpers are unlikely to ever reach the strength for towing of a common every day ordinary Class III hitch such as the factory one for the 80. Not even close. A Class III hitch has longitudinal runners along both frame members, and a truly massive cross member that is possibly stronger than the 80's frame is. Combined with multiple bolts through the frame, this creates a towing mount that meets the DOT's requirements.
...

Agree, disagree. How many bumpers have you used? Agree that some are relatively weak, use less bolts, etc. Disagree that all are that way. Some use all of the "hitch bolts" then also use the spare cross member bolt holes, so bolt on in two plains. They have the same size hitch cross member, then are also supported by the bumper shell, 3/16" or 1/4" steel. This forms a very solid box section, IMHO stronger than a std hitch.

... The Class III mount strategy also has to be extremely strong so that in a heavy rear crash the hitch will not fold and punch a hole in the fuel tank. They are tested specifically for this so the vehicle is as safe against fuel leakage with a hitch as it is without.
...

Lets just say; if you are in an accident that causes the hitch to be driven through the axle and into the gas tank, a little fuel leakage is likely to be the least of your worries. It's likely that you will never have any more worries!

The reason that more hitches are not tow rated, is because the government bribery (testing) is very costly, a barrier to entry for small companies or small production run models.