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Topic: When to replace the hitch pin?

Posted By: swimmer_spe on 08/03/23 08:13pm

The pin for holding the hitch into the receiver is the only real thing holding our trailers to our trucks. Mine is new, but it got me thinking, how often should it be replaced?


Posted By: JRscooby on 08/04/23 04:32am

Do you really think that little pin has that much force on it towing a trailer?
I think there is a lot of friction with the TW pushing down causing the 2 square tubes to bind together. And if the ball mount is not removed often, rust will lock them together. I pull my ballmount whenever I unhook. Pin in hand, I'm certain I would notice before it failed under load. Bet most wear on the pin is when trailer is not hooked up.
Now I do keep both the pin, and the safety pin that holds it in place in my "in case" tool box. Don't expect to break, but I have lost a few.


Posted By: bucky on 08/04/23 04:35am

Safety chains are the back up for those pesky pins.
I only replace them when I have no idea where I put it. For years now I have put it back in the receiver when finished towing.


Puma 30RKSS



Posted By: nickthehunter on 08/04/23 06:13am

When was the last time you have seen someone break a pin?


Posted By: ferndaleflyer on 08/04/23 06:30am

Not a pin but I once had a ball shear off where the rounded part starts. The lower part was still in place. This happened at 70 mph on I-40 the Friday evening before the 4th of July. Thanks to safety chains and a big enough truck damage was minimal. But what a traffic mess. I guess a pin could fail.


Posted By: opnspaces on 08/04/23 08:03am

If the pin is smooth and undamaged I would leave it alone. I would replace it if it's showing signs of damage like maybe the receiver tube gouging into the surface of the pin.

A few weeks ago I noticed that a replacement pin for a 2 inch receiver is a whole $3 on Amazon. At that price I ordered a few extras since I have multiple hitches at home. I also keep an extra in the center console of the Suburban as a just in case.
Amazon


2001 Suburban 4x4. 6.0L, 4.10 3/4 ton
2005 Jayco Jay Flight 27BH
1986 Coleman Columbia Popup.


Posted By: mleekamp on 08/04/23 08:13am

x2 on everything opnspaces said.

I not only keep an extra hitch pin, but a few extra clips as I find they walk off on occasion...and it's NEVER my fault. [emoticon]


Posted By: Grit dog on 08/04/23 10:27am

bucky wrote:

Safety chains are the back up for those pesky pins.
I only replace them when I have no idea where I put it. For years now I have put it back in the receiver when finished towing.

Lol, really? Not the replacing part, the safety chain part…unless I missed the sarcasm, in which case, a hearty LOL!


2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold


Posted By: Grit dog on 08/04/23 10:28am

opnspaces wrote:

If the pin is smooth and undamaged I would leave it alone. I would replace it if it's showing signs of damage like maybe the receiver tube gouging into the surface of the pin.

A few weeks ago I noticed that a replacement pin for a 2 inch receiver is a whole $3 on Amazon. At that price I ordered a few extras since I have multiple hitches at home. I also keep an extra in the center console of the Suburban as a just in case.
Amazon


$3 Scamazon hitch pins are maybe not the best purchase…I’ll leave it at that.


Posted By: Grit dog on 08/04/23 10:30am

nickthehunter wrote:

When was the last time you have seen someone break a pin?


Break? Never.
Bend? Only when used with a reduced sleeve.
Noticeable loss of cross sectional area due to wear? VERY rarely and likely a pin in daily use for decades.


Posted By: Grit dog on 08/04/23 10:33am

swimmer_spe wrote:

The pin for holding the hitch into the receiver is the only real thing holding our trailers to our trucks. Mine is new, but it got me thinking, how often should it be replaced?


I’ll wager a large sum that if you’re ever able to put any significant wear and tear on your hitch pin, by the time that happens, 95% of the current rvnet members will be pushing daisies and I will, at a minimum, be long since retired and on here babbling about hitch pins and other non issues, or also in the ground looking up.


Posted By: NMDriver2 on 08/04/23 03:42pm

If I exposed my pin or any part of my vehicle or attachment hardware to a salt environment I would look for rust each time I used it and replace if it looked weakened.

I've got one pin that I have used 23 years with out any wear or tear. Mostly used to pull the boat and light weight trailers (less than 3000lbs) behind my Astro van. I guess if I lived where rust was an issue I might worry about it or the hitch bolts, welds and other attachment hardware. My truck pulls the 5er and not much else. I do have a spare hitch pin for it somewhere but when I was pulling doubles I used the pin from the van in the 5er hitch to pull the boat. It has been dipped into salt water a time or two but then washed off as soon as possible with fresh water along with the rest of any metal I had near the sea.


Turret Class traveler


Posted By: swimmer_spe on 08/04/23 03:45pm

OP here.

I tend to replace by loosing them. I have yet to have one look rusted or have any marks on it. I also don't like the idea of replacing it only when the safety chains are used.


Posted By: JRscooby on 08/04/23 03:58pm

swimmer_spe wrote:

OP here.

I tend to replace by loosing them. I have yet to have one look rusted or have any marks on it. I also don't like the idea of replacing it only when the safety chains are used.

Something I have never thought of before; If safety chains are used, get a unknown shock load, should they be replaced?


Posted By: mosseater on 08/04/23 04:08pm

Any idea what the shear forces required to chop it in two? There are anomalies in this world but betting the farm very few ever are sheared. The receiver welds would probably fail before that pin would shear. I'd sooner keep the one I have road tested than risk a new one these days.


"It`s not important that you know all the answers, it`s only important to know where to get all the answers" Arone Kleamyck
"...An unarmed man can only flee from evil, and evil is not overcome by fleeing from it." Col. Jeff Cooper
Sunset Creek 298 BH



Posted By: Lawman5383 on 08/06/23 07:48am

I've been in RV transport for a while now and have never seen or heard of a pin failing. This is not to say they couldn't fail. Prior to this I was a police officer for 29 years and never heard of an accident caused by a pin failure.


2007 Cedar Creek Silverback 33LBHTS 5th Wheel
2007 Ford F350 SRW 6.0 PSD Crew Cab FX4 Reese 18K Signature Series 5er Slider Hitch
Allen the Dad, Robin the Mom, Maddy 6, Josh 4, and Rusty the meanest 15 lb Cairn Terrier Puppy ever.



Posted By: Grit dog on 08/06/23 08:35am

mosseater wrote:

Any idea what the shear forces required to chop it in two? There are anomalies in this world but betting the farm very few ever are sheared. The receiver welds would probably fail before that pin would shear. I'd sooner keep the one I have road tested than risk a new one these days.


Bout 28000lbs. Times 2 of course since there’s 2 shear planes.
This is not has not been and won’t ever be an issue. Nor is wearing one out.


Posted By: valhalla360 on 08/06/23 09:17am

mosseater wrote:

Any idea what the shear forces required to chop it in two? There are anomalies in this world but betting the farm very few ever are sheared. The receiver welds would probably fail before that pin would shear. I'd sooner keep the one I have road tested than risk a new one these days.


5/8inch pin has a cross sectional area of around 0.30in^2.

It will depend on the specific steel but say we made one of iron (not steel for a worst case scenario). Iron has a shear strength of around 26,000PSI.

So each end of the pin would have a strength of around 7,800 but since both ends would have to shear to get a failure, 15,600lb.

A descent quality steel (nothing exotic) can be twice that shear strength.

Keep in mind, when you tow, you aren't lifting the weight of the trailer. The force needed to pull the trailer is a small fraction of the trailer weight. Even in a panic stop, the trailer would push the truck into a skid long before the force reached the weight of the trailer.

So long as there is no sign of damage or deformation, it should be fine.


Tammy & Mike
Ford F250 V10
2021 Gray Wolf
Gemini Catamaran 34'
Full Time spliting time between boat and RV



Posted By: Grit dog on 08/06/23 09:55am

^Nope, but those may be good numbers for aluminum or brass or something. Hence why there’s no such thing as an aluminum hitch pin. You could rip 15000lbs in half just puttin the wood to it pulling your camper out of the driveway. (Not literally but it likely would not make it to the first campground.)
Any good hitch pin and maybe even the cheap $3 ones is going to have a shear strength FAR greater. Take normal 36ksi yield mild steel (that’s tensile strength). Ultimate tensile is more like 50ksi. Round numbers and approx.
Hitch pins are or should be 50-60-80ksi steel and shear is about 80% of tensile.

The factor of safety is 5-10 or idk maybe more.

Now bending is a different story. And why those silly reducer inserts for the trucks with 2.5-3” hitches are a horrible solution to being cheap with your hitch stingers.
The insert creates a short bending moment in the hitch pin and can and will easily pretzel a hitch pin. (And Waller out the holes in your hitch receiver, generally prior to bending the pin.)
I’ve cut off numerous bent pins due to those stupid little accessories.


Posted By: Cummins12V98 on 08/06/23 10:13pm

Quality US Made pin should never sheer.


2015 RAM LongHorn 3500 Dually CrewCab 4X4 CUMMINS/AISIN RearAir 385HP/865TQ 4:10's
37,800# GCVWR "Towing Beast"

"HeavyWeight" B&W RVK3600

2016 MobileSuites 39TKSB3 highly "Elited" In the stable

2007.5 Mobile Suites 36 SB3 29,000# Combined SOLD


Posted By: Grit dog on 08/06/23 11:08pm

A cheap one won’t shear either. Maybe unless your trailer rear ended by a loaded semi truck while you simultaneously an actual brick wall in front of you.


Posted By: valhalla360 on 08/07/23 07:03am

Grit dog wrote:

^Nope, but those may be good numbers for aluminum or brass or something. Hence why there’s no such thing as an aluminum hitch pin. You could rip 15000lbs in half just puttin the wood to it pulling your camper out of the driveway. (Not literally but it likely would not make it to the first campground.)
Any good hitch pin and maybe even the cheap $3 ones is going to have a shear strength FAR greater. Take normal 36ksi yield mild steel (that’s tensile strength). Ultimate tensile is more like 50ksi. Round numbers and approx.
Hitch pins are or should be 50-60-80ksi steel and shear is about 80% of tensile.

The factor of safety is 5-10 or idk maybe more.

Now bending is a different story. And why those silly reducer inserts for the trucks with 2.5-3” hitches are a horrible solution to being cheap with your hitch stingers.
The insert creates a short bending moment in the hitch pin and can and will easily pretzel a hitch pin. (And Waller out the holes in your hitch receiver, generally prior to bending the pin.)
I’ve cut off numerous bent pins due to those stupid little accessories.


Show me a strain guage showing 15k lbs on a 10,000 lb bumper pull. A truck with 7000 on the rear axle and sticky tires with a 50% coefficient of friction with only be able to apply 3500lb of shear force to the pin. Lock up all 4 wheels on a 10,000 lb truck and you are around 5000lb applied to the pin. But in normal use even those numbers are unrealistically high.

Also, try reading....I specifically said iron not steel as a worst case scenario and that steel can easily double the strength.

This is a shear failure so work in shear strength not tensile strength.

If you start mismatching parts of course you can have problems.

The point is even with the worst case scenario the pin is still several times stronger than needed.


Posted By: Grit dog on 08/07/23 09:57am

^Yup, you’re correct. Although also correct. I didn’t pickup on your reference to iron, as in cast iron, of which NO hitch pins are made of. And I understand this concept better than most.
Why would you even say that? Be like using a wooden dowel or titanium as odd ball “examples”.
Although the silly original question may have prompted your almost as silly comparison?

3 pages in, it’s a hitch pin, it’ll be fine. End of story. OP can now sleep well with visions of hitch pins NOT breaking dancing in his head!


Posted By: opnspaces on 08/07/23 10:57am

Grit dog wrote:

opnspaces wrote:

If the pin is smooth and undamaged I would leave it alone. I would replace it if it's showing signs of damage like maybe the receiver tube gouging into the surface of the pin.

A few weeks ago I noticed that a replacement pin for a 2 inch receiver is a whole $3 on Amazon. At that price I ordered a few extras since I have multiple hitches at home. I also keep an extra in the center console of the Suburban as a just in case.
Amazon


$3 Scamazon hitch pins are maybe not the best purchase…I’ll leave it at that.


I stand by my first post. It's a Curt pin not a no name overseas knockoff. Here's another link to the Curtmfg.com website where the pin lists for $4.95 if it makes anybody feel better about purchasing.
Curtmfg


Posted By: swimmer_spe on 08/07/23 12:51pm

valhalla360 wrote:

mosseater wrote:

Any idea what the shear forces required to chop it in two? There are anomalies in this world but betting the farm very few ever are sheared. The receiver welds would probably fail before that pin would shear. I'd sooner keep the one I have road tested than risk a new one these days.


5/8inch pin has a cross sectional area of around 0.30in^2.

It will depend on the specific steel but say we made one of iron (not steel for a worst case scenario). Iron has a shear strength of around 26,000PSI.

So each end of the pin would have a strength of around 7,800 but since both ends would have to shear to get a failure, 15,600lb.

A descent quality steel (nothing exotic) can be twice that shear strength.

Keep in mind, when you tow, you aren't lifting the weight of the trailer. The force needed to pull the trailer is a small fraction of the trailer weight. Even in a panic stop, the trailer would push the truck into a skid long before the force reached the weight of the trailer.

So long as there is no sign of damage or deformation, it should be fine.


Thank you for the math.

Now, what about fatigue? If you bought it brand new and it is used regularly and is 10,20+ years old?


Posted By: SUMRX4 on 08/07/23 03:46pm

The pin really isn't holding any weight. I towed an 8,000Lb tractor on a flatbed trailer about 60 miles once and after the trip I realized I never put the pin into the hitch. Won't do that again but that taught me the pin isn't doing any work.


Posted By: JRscooby on 08/07/23 04:13pm

SUMRX4 wrote:

The pin really isn't holding any weight. I towed an 8,000Lb tractor on a flatbed trailer about 60 miles once and after the trip I realized I never put the pin into the hitch. Won't do that again but that taught me the pin isn't doing any work.



Thank you.
I have had to cut pins to get them out when somebody did something silly like put cable in receiver, then pin thru eye, but then all the force is center of pin. But I have had to cut more of the locking pins, where snot gets in key-hole, key won't work


Posted By: Grit dog on 08/08/23 12:35am

SUMRX4 wrote:

The pin really isn't holding any weight. I towed an 8,000Lb tractor on a flatbed trailer about 60 miles once and after the trip I realized I never put the pin into the hitch. Won't do that again but that taught me the pin isn't doing any work.


Your confusing ignorance and luck with physics….


Posted By: JRscooby on 08/09/23 04:37am

Grit dog wrote:

SUMRX4 wrote:

The pin really isn't holding any weight. I towed an 8,000Lb tractor on a flatbed trailer about 60 miles once and after the trip I realized I never put the pin into the hitch. Won't do that again but that taught me the pin isn't doing any work.


Your confusing ignorance and luck with physics….


There have been times when I have had to telescope dry tubes. The only way to do it with reasonable amount of force is make sure there is no side pressure. If you lift the ball mount too high it is harder to get it out. The same would apply with TW on the ball


Posted By: Grit dog on 08/09/23 08:12am

swimmer_spe wrote:

valhalla360 wrote:

mosseater wrote:

Any idea what the shear forces required to chop it in two? There are anomalies in this world but betting the farm very few ever are sheared. The receiver welds would probably fail before that pin would shear. I'd sooner keep the one I have road tested than risk a new one these days.


5/8inch pin has a cross sectional area of around 0.30in^2.

It will depend on the specific steel but say we made one of iron (not steel for a worst case scenario). Iron has a shear strength of around 26,000PSI.

So each end of the pin would have a strength of around 7,800 but since both ends would have to shear to get a failure, 15,600lb.

A descent quality steel (nothing exotic) can be twice that shear strength.

Keep in mind, when you tow, you aren't lifting the weight of the trailer. The force needed to pull the trailer is a small fraction of the trailer weight. Even in a panic stop, the trailer would push the truck into a skid long before the force reached the weight of the trailer.

So long as there is no sign of damage or deformation, it should be fine.


Thank you for the math.

Now, what about fatigue? If you bought it brand new and it is used regularly and is 10,20+ years old?

A. His “math” ain’t right for STEEL, which all hitch pins are made of. And a “decent quality” steel is far more than double the shear value of cast iron.
B. “Fatigue” isn’t a real world consideration unless you could somehow get enough stress into it to have repeated elastic deformation (you can’t and won’t) resulting in strain hardening which will eventually leading to cracking.
However plastic deformation would cause it to be rendered unsafe. Never gonna happen with a proper hitch setup but somewhat common when those silly hitch stinger reducers are used on larger receivers to fit smaller stingers.
Finally physical wear could cause it to have reduces strength. For steel rigging subject to cross sectional loss due to wear, the criteria is a reduction of 10% or more of the effective cross section.

At the end of the day, unless you bend a pin as I described above, there is a 99.9999% chance that pin will outlast you, and your kids too. Maybe grandkids as well.


Posted By: Grit dog on 08/09/23 08:14am

JRscooby wrote:

SUMRX4 wrote:

The pin really isn't holding any weight. I towed an 8,000Lb tractor on a flatbed trailer about 60 miles once and after the trip I realized I never put the pin into the hitch. Won't do that again but that taught me the pin isn't doing any work.



Thank you.
I have had to cut pins to get them out when somebody did something silly like put cable in receiver, then pin thru eye, but then all the force is center of pin. But I have had to cut more of the locking pins, where snot gets in key-hole, key won't work


An extreme example of the same thing that happens with reducer sleeves sometimes.


Posted By: valhalla360 on 08/09/23 01:32pm

Grit dog wrote:

^Yup, you’re correct. Although also correct. I didn’t pickup on your reference to iron, as in cast iron, of which NO hitch pins are made of. And I understand this concept better than most.
Why would you even say that? Be like using a wooden dowel or titanium as odd ball “examples”.


I never said "cast iron" which is an entirely different material and completely unsuitable as it's highly brittle. I used "iron" as I'm not sure of the exact formulation of steel used and the strength can vary wildly based on the specific formulation (though typically far stronger than iron), so iron provides a lower floor on strength...and it's still several times stronger than is required.


Posted By: valhalla360 on 08/09/23 01:44pm

swimmer_spe wrote:

valhalla360 wrote:

mosseater wrote:

Any idea what the shear forces required to chop it in two? There are anomalies in this world but betting the farm very few ever are sheared. The receiver welds would probably fail before that pin would shear. I'd sooner keep the one I have road tested than risk a new one these days.


5/8inch pin has a cross sectional area of around 0.30in^2.

It will depend on the specific steel but say we made one of iron (not steel for a worst case scenario). Iron has a shear strength of around 26,000PSI.

So each end of the pin would have a strength of around 7,800 but since both ends would have to shear to get a failure, 15,600lb.

A descent quality steel (nothing exotic) can be twice that shear strength.

Keep in mind, when you tow, you aren't lifting the weight of the trailer. The force needed to pull the trailer is a small fraction of the trailer weight. Even in a panic stop, the trailer would push the truck into a skid long before the force reached the weight of the trailer.

So long as there is no sign of damage or deformation, it should be fine.


Thank you for the math.

Now, what about fatigue? If you bought it brand new and it is used regularly and is 10,20+ years old?


Never heard of one that has failed. I suppose if you do something utterly stupid, it's possible but just no a big concern.

The above would be a worst case where the pin is providing all the pulling and stopping power.
- As noted by others, the friction in the receiver tube provides much of the pulling power. Particularly with a WDH, it's not just the dead weight on the hitch creating friction.
- The trailer brakes should provide most of the stopping power.
- The maximum pulling power before the drive axle wheels spin is a tiny fraction of the strength.
- In practice, it's probably less than 10% of the trailer weight just rolling down a level highway. Going up a 6% grade, it should be 6% plus wind resistance...maybe 1500-2000lb of force.

Fatigue in that scenario isn't really a concern. If you have a 20yr old pin that's been in use daily with the truck maxed out on tow rating, go ahead and replace it if it makes you feel better but it's not an issue.


Posted By: Grit dog on 08/09/23 02:06pm

valhalla360 wrote:

Grit dog wrote:

^Yup, you’re correct. Although also correct. I didn’t pickup on your reference to iron, as in cast iron, of which NO hitch pins are made of. And I understand this concept better than most.
Why would you even say that? Be like using a wooden dowel or titanium as odd ball “examples”.


I never said "cast iron" which is an entirely different material and completely unsuitable as it's highly brittle. I used "iron" as I'm not sure of the exact formulation of steel used and the strength can vary wildly based on the specific formulation (though typically far stronger than iron), so iron provides a lower floor on strength...and it's still several times stronger than is required.


OMG you should give up arguing about this…. You’re not making any tangible sense, especially in the context of this (ridiculous) original question.
So wrought iron, or pig iron ? which is basically just high carbon ore, not actually made into any final product.). And none of which are made into hitch pins.

* This post was edited 08/09/23 10:49pm by Grit dog *


Posted By: Cummins12V98 on 08/12/23 08:13am

Does my CUMMINS-HEMI have a hitch pin?????


Posted By: valhalla360 on 08/12/23 08:23am

Grit dog wrote:


OMG you should give up arguing about this…. You’re not making any tangible sense, especially in the context of this (ridiculous) original question.
So wrought iron, or pig iron ? which is basically just high carbon ore, not actually made into any final product.). And none of which are made into hitch pins.


So you don't understand anything about metallurgy and are just going to throw out terms with "iron" in them hoping something sticks.

In engineering, we often use a worst case scenario (with a factor of safety) when the full information isn't readily available...but I'm sure you know better even if you don't bother reading the full post.


Posted By: BarneyS on 08/12/23 08:58am

I'm sure the OP has the idea by now and since the bickering has started I am going to close this one. Thanks for all your participation.
Barney


2004 Sunnybrook Titan 30FKS TT
Hensley "Arrow" 1400# hitch (Sold)
Not towing now.
Former tow vehicles were 2016 Ram 2500 CTD, 2002 Ford F250, 7.3 PSD, 1997 Ram 2500 5.9 gas engine



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