my Highlander's Curt hitch broke again!

[Mike Magee]

I tow close to 25,000 miles per year with my '08 Highlander. I installed a Curt hitch early on, and after about 1 year it broke on the passenger side. Curt replaced it at no cost to me. The replacement featured a somewhat stronger design at that point. I would get underneath occasionally to check bolt tightness and inspect, but after a couple years went by I didn't bother looking any more... all was well.

Now, 3 years later, the replacement broke again. I had just stopped at a city intersection and then turned left... going about 10 mph when I heard a CLUNK... SCRRRAAAAAAAAPE. Uh-oh, I've heard that sound before! Sure enough, the new one broke in the same place as the old one.
Here's the dangling end of the receiver:


And here's the other end, next to the muffler:



Ok, so I decided to weigh my trailer tongue as carefully as possible today (it's fully loaded for work again) and my tongue weight is 425 lbs. Trailer weight is probably about 3600 or so, no way is it ever over 4000 lbs. However, when I got underneath and removed the broken receiver, I found this on the other, driver's side:



The Highlander has a 5000/500 tow rating. It has 112K miles on the odometer, with about 85% of that with a trailer (this one or a lighter travel trailer) behind it.

You can see on the receiver pics that the upper part of the break is rusted a bit, while the bottom is shiny. This tells me that the upper part broke a while ago (perhaps a few weeks?) and the shiny part is the part that finally gave way yesterday. I am wondering if this partially-broken condition allowed the receiver to flex enough to cause the cracks in the Highlander's body on the other side; the receiver on that side was simply a flat plate held up with 3 bolts. I wish they had made a vertical support piece there, like they did on the passenger side.

I'm getting a different brand of receiver on Monday. If it does not have a vertical support on both sides, I think I'll take it to a welding shop and have some supports added. I certainly don't trust that cracked bolt hole any more, but a vertical piece would keep the receiver from going anywhere.

[Donna D.]

Mike, I can't offer anything other than my sympathy and support and OMG at least you weren't cruisin on a freeway! Although I'd definitely let Curt know... not so much that they'd offer a replacement (which sounds like you don't want), but it helps manufacturers keep track of quality control (like a bad batch in a bad year).

Safe travels

[Greg H]

I've said this before, Curt hitches are junk. Now someone here swears bye them, I'm sure he'll chime in soon.
Replace the junk with a Reese or a Draw Tight.

[Frederick L. Simson]

Originally Posted by Mike Magee

Sure enough, the new one broke in the same place as the old one.
Here's the dangling end of the receiver:

I've long been curious about the reliability of receivers that have to weld in a separate piece to circumnavigate around the vehicle's exhaust system. I doubt that it is exclusively Curt's manufacturing failure but possibly a design flaw with the vehicle itself. My Odyssey's exhaust system is outside of the hitch receiver's footprint and doesn't have to be compensated for.

My first receiver was a square tube Reese, which broke just behind both forward mounting holes, reducing the 6 attachment points to 4. (So much for relying on a name brand) I searched for a Reese replacement without success, and square tube design was also unavailable in the receivers that I could find. My current receiver does not have a brand label on it. Searching the capacity label turns up, in very small print: "Cequent Towing Products."

[Orcus79]

The other option would be to get the factory hitch installed. Before you get any hitch installed you need to have the frame area inspected and repaired.

You are right on the broken side being the cause of the damage on the other as now you would have a very nice lever and all the force on that side of the frame.

[BCDave]

Originally Posted by Greg H

I've said this before, Curt hitches are junk. Now someone here swears bye them, I'm sure he'll chime in soon.
Replace the junk with a Reese or a Draw Tight.

waddaya mean they're junk?

Why I've had mine for almost a whole day and its only broken twice!

(and I was gonna actually INSTALL it next week, too!)

[Mike Magee]

Actually this was the 4th Curt hitch for this vehicle. The first one would not fit (2 bolt holes were drilled a little off on one side). The second one was badly warped and didn't even come close to fitting. The third hitch was the one that made it about 1 year. That one, Donna, did break at about 60 mph on the turnpike expressway.

But when they break, it's on just the one side. the other side is still intact (it bends but holds). The broken side drops down and scrapes the pavement. But the trailer doesn't get away.

[Raz]

Was the "still connected" side where the body damage has occured? I'm thinking the torque on the remaining hitch caused the cracks. Raz

[Mike Magee]

It's possible, Raz, although at 10 mph there hardly was any extra stress. Plus when it happened the previous time at high speed, it did not harm the Toyota. But anything's possible.

[ruscal]

Unibody or monoqoque construction gets its strength from boxing sheet metal to form structural members. Most modern cars use this type of construction Attaching a rigid frame to one of those type structures is difficult, often requiring spreading the load out along the sheet metal box. The hitch designers have to work under space restrictions and avoid exhaust components, fuel tanks, spare tires, etc. By avoiding those things, they sometimes have to compromise the perfect or best connection. They also have to design their products at a price point. The result is that the connection flexes because the geometry of the joint is not optimal due to the constraints. The flexing of the metal causes fatigue, like when you bend wire back and forth until it comes apart. The farther the metal is flexed, the fewer cycles it can flex before failure. You probably can see more failures in one company's products than another due to how they engineered those connections. They could come up with a strong enough design if we could afford to pay what ever cost it took to accomplish, but this is the real world and cost does matter to most folks. In the older cars before unibody, hitch cross members where simply attached to the main vehicle frame rails. These were typically 1/8" thick steel channels or boxes. Truck frames still use this construction. Attachment to those frames was pretty easy to get right and failure was rare. The best way to attach a hitch to a unibody is when the vehicle manufacturer provides the mounting points pre-engineered into the structure. And yes if one side of your hitch mount pulls loose it will destroy the other side regardless of vehicle speed.

Disclaimer: I aren’t a ingineer, but I tinkers with metal a little.

[Andrew Gibbens]

In case anyone else but me can't work out what the pictures show, here is the complete hitch:

[Raz]

Etrailer shows 4 hitches. Each has a different mount. While two go over the muffler and two under, they all have the loop around the muffler that failed here.

[honda03842]

We have a Curt Hitch as well. Our hitch has a third tie point besides the two side 'rails', it ties to the tow loop in the center of the Honda behind the bumper. Our hitch cracked at this tow point connection.

This point from an engineering stand point is the high stress point because the loop is cylindrical and creates a high pressure line contact to a flat surface.

Curt replaced our hitch with an identical hitch. I had this area on the replacement hitch thickened by welding an additional thickness of material to this location. Subsquently Curt eliminated this tie point.

Our first trip was the rough Labrador 'dirt' highway. On the trip I regularly checked the rail mounts for tightness but never the third tie point. Definitely a mistake. Regularly checking your hitch is mandatory and as well as the tow vehicle connection points. (Just as checking the locking of your ball is critical.)

I suspect most hitch failure results from flexure. In my case because something was not tight.

I will say Mike's trailer is substantially heavier than mine, my hitch weight is only 200 lbs and my trailer weighs only 2400 lbs.

Safe travels

[cpaharley2008]

Perhaps after market "bolt on" accessories should be avoided and owners should purchase vehicles with factory hitches. Not aware of any OEM failures.

[ruscal]

You could have a metal fabricator add another heavy strap under the muffler. It would have to be "bolt on" so it could be removed. If it were done in such a way as to add stiffness to the cross member, it should buy you more time before failure.
Russ

Could the exhaust pipe be turned down before getting to the hitch cross member? If so you could modify the hitch to have the tube go all the way accross. The exhaust is easy to modify, provided there is room.

[Laura & Rick]

The OEM hitch is a different design than the after market hitches. It "blends" into the bumper such that the attachment points do not need the loop around the muffler. And, being at bumper height, the OEM hitch is higher off the ground preventing any scraping with the ground. The OEM hitch is expensive compared to after market hitches but does not have any issues that come with the after market hitches.

[Mike Magee]

That's interesting about the OEM hitch, I haven't noticed one (either they really do blend in, or they're so expensive no one buys them, not sure which!).

I found a Draw Tite "Max-E Loader" model that has vertical pieces on both sides. I'm going to see about getting one of those. I did think about having the existing hitched repaired and reinforced, but the labor would probably come close to the cost of the new one (about $225).

[Roger Kimble]

I had a Curt hitch on my Chevy 1500 van, it rusted out in Michigan, I replaced it with a Curt catagory 1V, the old one was a 1996 model

[Perry J]

I think U-Haul is the King of Hitch installers.
Why not try them?
I have used their hitches for years.
Towing everything from 6 horse trailers, stock trailers to my Lil Bigfoot and have never had a problem.
John

[Bill MacDermod]

Originally Posted by cpaharley2008

Perhaps after market "bolt on" accessories should be avoided and owners should purchase vehicles with factory hitches. Not aware of any OEM failures.

\

I agree, I'm thinking the weight rating of 5,000 lbs is with the factory towing pkg and not after market