Has anyone had any experience with this coupling [3.5t Automatic McHitch Coupling ].We are considering converting from ball coupling.Would therefore be very appreciative of any comments fellow forum members might have.Our van has a ball weight of approximately 320kg. Gross being 3250kg.Should we consider 4.5t unit.Any replies greatfull.
Plendo said
02:26 PM Sep 14, 2014
I have been considering it, but dealer advised against it if I plan to run a WDH, I do not, so that is not an issue.
Currently working out how it will work once it has a little wear, imagine truing to reverse in to hook up if the bit that plugs in is drooping because the uni has loosened up?
Dougwe said
05:45 PM Sep 14, 2014
I have seen a few of the older one's in use during my travels, not the auto though.
Talking to the drivers they are more than happy with them. I have been keen myself for some time but couldn't justify one for the Avan but now a new Den is on the horizon I will look into the auto one for sure. I just need to make sure a solo person can hook into one ok. I use a hitch guide now so see the auto Mc hitch doing similar things.
moamajohn said
08:48 PM Sep 14, 2014
Hi Ascot . Yep we have one ,magnificent in a word .Our is a supreme Classic 2400kg 240 on the ball.We also have a WDH [with sliders and it all works perfect after 3 wks and 5000 kays last month] thats it mate pure and simple.!! I would only take heed of any comments on this topic from those that have one otherwise it is only ones opinion of an item that they have never used.I also recently had ESC fitted but as I have not been on a journey of a worthy distance as yet I too am not a reliable user of this item as yet . Cheers John P.S. ring The Co for advice as they bend over B/wards to assist.
I am a mechanical engineer, and in my opinion I would not use one of these hitches unless I saw the full engineering calculations around the universal joint and flanges.
Universal joints are used to transmit torque, and a small amount of accompanying rotational shear stress.
As a caravan coupling, these components are transmitting axial loads including bending moments and axial shear stress.
I would take a lot of convincing before I would ever use one.
Peter
PJK
blaze said
06:02 PM Sep 15, 2014
Universal joints are designed to run at a minimum degree angle and a maximum degree angle and if they fall outside those parameters they will prematurely fail. They are not designed to run level as in the hitch travelling up the tar.
cheers
blaze
justcruisin01 said
03:00 PM Sep 16, 2014
There are max deg angles when rotating, in this situation there is no rotation.
oldboar said
04:10 PM Sep 16, 2014
I love seeing the "X" spurts knock anything different particularly items that have undergone stringent design & testing procedures before being offered for sale. We have the 3.5 tonne older McHitch on our 2.75 tonne Coromal which has now done more than 40,000 km around Australia with no problems. We initially chose it for two reasons
1. Makes the van far less attractive to thieves due to the tapered pin rather than the far more common ball, &
2. A van rollover is far more likely to merely lift the rear of the tug, rather than rolling it as well.
Another point we've since noted is that with the movement not being at the ball less stress is placed on the drawbar with extreme angles & that ball wear is non-existent.
During our trip we've seen two snapped balls & a bent drawbar. All were the 50mm ball & coupling system. I wonder how many rollovers were.
Darrell & Sandra.
Baz421 said
04:40 PM Sep 16, 2014
oldboar wrote:
I love seeing the "X" spurts knock anything different particularly items that have undergone stringent design & testing procedures before being offered for sale. We have the 3.5 tonne older McHitch on our 2.75 tonne Coromal which has now done more than 40,000 km around Australia with no problems. We initially chose it for two reasons 1. Makes the van far less attractive to thieves due to the tapered pin rather than the far more common ball, & 2. A van rollover is far more likely to merely lift the rear of the tug, rather than rolling it as well.
Another point we've since noted is that with the movement not being at the ball less stress is placed on the drawbar with extreme angles & that ball wear is non-existent.
During our trip we've seen two snapped balls & a bent drawbar. All were the 50mm ball & coupling system. I wonder how many rollovers were.
Darrell & Sandra.
I have no problem with what you say, and we have a Hyland Hitch on our van. All OK.
This is a complex area and no one has even scratched the surface with expertise. What about implied load - ie when a standard ball with 15 degree horizontal tilt limit, reaches its limit. It puts part of the load on the tug and "may" avoid a rollover SIMILAR TO THE PURPOSE OF A SINGLE ACTING (semi floating) TURNTABLE on semis and some fifth wheelers.
Is it better to:- roll the van only OR have an implied load transferred to the tug and avoid a van rollover OR roll the van and tug together??? None preferably eh!
There are heaps of other factors and one which you mention in point 2 above is - the van pulling the tug side ways if it rolls,,, I can confidently say that if the van rolls the dynamics of the roll can also roll the tug, simply by pulling the rear of the tug to one side, and the wonderful tyres you paid heaps for grip so well the tug is pulled sideways ESPECILALY if tug brakes are touched, and over they go together.
So as you can see from a non expert it aint easy and there is bias everywhere, BUT I agree users are in the best position to comment.
I respect logical opinions including yours and moamajohn's in aprevious post.
-- Edited by Baz421 on Tuesday 16th of September 2014 05:30:10 PM
Plendo said
04:42 PM Sep 16, 2014
Darrell, you have had your Mchitch for a while, it has done a significant number of KM, thus you will be able to answer the concern I posted earlier.
Does the forward unsupported part of your hitch still sit up, or has the uni joint slackened off and the free part sags ?
I am particularly interested in this, as it would be critical with the new automatic version with the horizontal pin.
Basically this is the only thing holding me back from getting one, and I have just been waiting for the opportunity to talk to people with McHitchs to confirm that it is not a problem.
Dougwe said
05:43 PM Sep 16, 2014
I must say everyone, I am looking in on this thread with much interest.
Keep all this good feed back and comments coming. The "Chief, Feather" might just be interested too.
oldboar said
07:36 PM Sep 16, 2014
Plendo, still sits up firmly. Thankfully, as I use that facility to hitch up solo ie tilt the front section so that when the tapered pin hits the rear of it's housing the front section is pushed down. Once I see that occur in my rear vision camera, I know I can complete connection without further movement of the tug.
Darrell
justcruisin01 said
08:01 PM Sep 16, 2014
Plendo wrote:
Darrell, you have had your Mchitch for a while, it has done a significant number of KM, thus you will be able to answer the concern I posted earlier.
Does the forward unsupported part of your hitch still sit up, or has the uni joint slackened off and the free part sags ?
I am particularly interested in this, as it would be critical with the new automatic version with the horizontal pin.
Basically this is the only thing holding me back from getting one, and I have just been waiting for the opportunity to talk to people with McHitchs to confirm that it is not a problem.
I dont have one as yet but looking at them, from what I see there are two of the uni cups that appear to be screwed in, hence the two holes in the end of each cup to accomodate a special tool, this being so maybe they can be adjusted if they should become loose due to extensive work.
As for this being knocked already , have a look at the hy-land hitch. Two studs fitted through a yoke & screwed into a cast tow ball cup , the hole van is attached to the tug via these two studs.
As a comparason, H/D towbars went away from the two stud bolt on tounge to the 50mm receiver many yrs back.
PJK said
10:26 PM Sep 16, 2014
oldboar wrote:
I love seeing the "X" spurts knock anything different particularly items that have undergone stringent design & testing procedures before being offered for sale. We have the 3.5 tonne older McHitch on our 2.75 tonne Coromal which has now done more than 40,000 km around Australia with no problems. We initially chose it for two reasons 1. Makes the van far less attractive to thieves due to the tapered pin rather than the far more common ball, & 2. A van rollover is far more likely to merely lift the rear of the tug, rather than rolling it as well.
Another point we've since noted is that with the movement not being at the ball less stress is placed on the drawbar with extreme angles & that ball wear is non-existent.
During our trip we've seen two snapped balls & a bent drawbar. All were the 50mm ball & coupling system. I wonder how many rollovers were.
Darrell & Sandra.
Oldboar, I am glad that you are happy with your coupling.
I don't wish failure on anyone, but when I see a mechanical component being used outside it's primary design purpose, with vastly differing load and stress applications, then I have to question it.
If as you say, the company have done their due diligence with engineering and testing, then it is quite possible that they are right and I am wrong. The original opinion (and it was only an opinion) that I expressed did state that I would want to review their data prior to using their coupling.
The past 22 years of my working life have been taken up in designing, building, and testing new lightweight components for marine hydraulics. Whilst these components had to be lightweight, they still had to pass all the Marine Survey testing and accreditation, and had to be reliable in service.
The universal joint in this coupling just plain looks like it is wrongly applied. It is the primary connection between tug and van, and in the event of a failure, only your safety chains and your skill as a driver to rely on averting a potential disaster.
Perhaps I need to think outside the box more, but at this stage it is a no go for me.
Peter
PJK
oldboar said
10:38 AM Sep 17, 2014
Peter, as you say, it is the primary connection between tug & van. However, I don't recall ever seeing or for that matter, hearing of, a universal coupling being virtually torn in half which would have to occur before the van & tug could part company. I have however, seen & heard of a number of 50mm tow ball shafts snapping. Is it not the primary connection in a ball & coupling system?
Darrell
Baz421 said
10:47 AM Sep 17, 2014
oldboar wrote:
Peter, as you say, it is the primary connection between tug & van. However, I don't recall ever seeing or for that matter, hearing of, a universal coupling being virtually torn in half which would have to occur before the van & tug could part company. I have however, seen & heard of a number of 50mm tow ball shafts snapping. Is it not the primary connection in a ball & coupling system?
Darrell
Uni joints do fail,, I've replaced a few years ago that failed,,, cars and trucks,,,, but on tailshafts and that is axial load at high revs/load
PJK said
03:01 PM Sep 17, 2014
oldboar wrote:
Peter, as you say, it is the primary connection between tug & van. However, I don't recall ever seeing or for that matter, hearing of, a universal coupling being virtually torn in half which would have to occur before the van & tug could part company. I have however, seen & heard of a number of 50mm tow ball shafts snapping. Is it not the primary connection in a ball & coupling system?
Darrell
Darrell, I agree that conventional couplings do break, be it the ball shaft, or the coupling, or how the coupling has been mounted.
Also don't dispute that there has to be a better system. One that immediately comes to mind is the Military type couplings, but they are noisy in use and have some fore and aft slop, so caravan owners probably would not like them.
I have seen the results of U-joint failures - automotive, agricultural, and industrial.
One of the most common causes of U-joint failure is due to not making sufficient allowance for shaft increase in length due to thermal expansion. The thermal expansion puts an axial load on the joint - exactly the type of load that this coupling will experience. (That is axial load caused by towing, not caused by thermal expansion.)
I just hope the manufacturers have done their homework.
Regards
Peter
PJK
Ascot said
07:12 PM Sep 17, 2014
Well thankyou to everyone who has voiced an opinion on my topic.You have all certainly added a lot of knowledge to the question.I think I will just sit for the moment and watch the future replies.I am certainly greatful for the time you all have taken to discuss this.
Plendo said
07:18 PM Sep 17, 2014
Thanks Darrell,
I am just waiting till my van is next out of storage, and it will get McHitched.
nissanpete said
03:50 PM Sep 21, 2014
Mate we have fitted a McHitch auto to our brand new Paramount Vogue all up weight of 3.250 tons. It is the greatest thing since the invention of the wheel for hitching up and unhitching. People should not criticize unless they have tried it. Had a Hyland on the last van loved that hitch but the Mchitch is a new style and it works great.
-- Edited by nissanpete on Sunday 21st of September 2014 03:52:09 PM
Bushie said
08:37 PM Mar 16, 2015
Sorry to wake this thread up, but looking at fitting a McHitch to our Pajero/van to solve the rear door issue, have spoke to McHitch directly
just seeking any updates on personal use of the hitch.
KevinC said
09:49 PM Mar 16, 2015
I have the original McHitch and love it. I probably won't bother updating because it ticks all the boxes for me. I tow a Jayco Sterling, about 2.8 tonnes at a guess.
BARME1 said
07:12 PM Nov 18, 2016
Hey mate weve just joined the site looking at the mchitch and WDH whats your wdh and your tow tug weve got THE 2014 bt 50 SUPREME 2015 EXC
Has anyone had any experience with this coupling [3.5t Automatic McHitch Coupling ].We are considering converting from ball coupling.Would therefore be very appreciative of any comments fellow forum members might have.Our van has a ball weight of approximately 320kg. Gross being 3250kg.Should we consider 4.5t unit.Any replies greatfull.
I have been considering it, but dealer advised against it if I plan to run a WDH, I do not, so that is not an issue.
Currently working out how it will work once it has a little wear, imagine truing to reverse in to hook up if the bit that plugs in is drooping because the uni has loosened up?
Talking to the drivers they are more than happy with them. I have been keen myself for some time but couldn't justify one for the Avan but now a new Den is on the horizon I will look into the auto one for sure. I just need to make sure a solo person can hook into one ok. I use a hitch guide now so see the auto Mc hitch doing similar things.
Sorry Ascot ,I forgot the pic.
Universal joints are used to transmit torque, and a small amount of accompanying rotational shear stress.
As a caravan coupling, these components are transmitting axial loads including bending moments and axial shear stress.
I would take a lot of convincing before I would ever use one.
Peter
PJK
cheers
blaze
There are max deg angles when rotating, in this situation there is no rotation.
1. Makes the van far less attractive to thieves due to the tapered pin rather than the far more common ball, &
2. A van rollover is far more likely to merely lift the rear of the tug, rather than rolling it as well.
Another point we've since noted is that with the movement not being at the ball less stress is placed on the drawbar with extreme angles & that ball wear is non-existent.
During our trip we've seen two snapped balls & a bent drawbar. All were the 50mm ball & coupling system. I wonder how many rollovers were.
Darrell & Sandra.
I have no problem with what you say, and we have a Hyland Hitch on our van. All OK.
This is a complex area and no one has even scratched the surface with expertise. What about implied load - ie when a standard ball with 15 degree horizontal tilt limit, reaches its limit. It puts part of the load on the tug and "may" avoid a rollover SIMILAR TO THE PURPOSE OF A SINGLE ACTING (semi floating) TURNTABLE on semis and some fifth wheelers.
Is it better to:- roll the van only OR have an implied load transferred to the tug and avoid a van rollover OR roll the van and tug together??? None preferably eh!
There are heaps of other factors and one which you mention in point 2 above is - the van pulling the tug side ways if it rolls,,, I can confidently say that if the van rolls the dynamics of the roll can also roll the tug, simply by pulling the rear of the tug to one side, and the wonderful tyres you paid heaps for grip so well the tug is pulled sideways ESPECILALY if tug brakes are touched, and over they go together.
So as you can see from a non expert it aint easy and there is bias everywhere, BUT I agree users are in the best position to comment.
I respect logical opinions including yours and moamajohn's in aprevious post.
-- Edited by Baz421 on Tuesday 16th of September 2014 05:30:10 PM
Darrell, you have had your Mchitch for a while, it has done a significant number of KM, thus you will be able to answer the concern I posted earlier.
Does the forward unsupported part of your hitch still sit up, or has the uni joint slackened off and the free part sags ?
I am particularly interested in this, as it would be critical with the new automatic version with the horizontal pin.
Basically this is the only thing holding me back from getting one, and I have just been waiting for the opportunity to talk to people with McHitchs to confirm that it is not a problem.
Keep all this good feed back and comments coming. The "Chief, Feather" might just be interested too.
Darrell
I dont have one as yet but looking at them, from what I see there are two of the uni cups that appear to be screwed in, hence the two holes in the end of each cup to accomodate a special tool, this being so maybe they can be adjusted if they should become loose due to extensive work.
As for this being knocked already , have a look at the hy-land hitch. Two studs fitted through a yoke & screwed into a cast tow ball cup , the hole van is attached to the tug via these two studs.
As a comparason, H/D towbars went away from the two stud bolt on tounge to the 50mm receiver many yrs back.
Oldboar, I am glad that you are happy with your coupling.
I don't wish failure on anyone, but when I see a mechanical component being used outside it's primary design purpose, with vastly differing load and stress applications, then I have to question it.
If as you say, the company have done their due diligence with engineering and testing, then it is quite possible that they are right and I am wrong. The original opinion (and it was only an opinion) that I expressed did state that I would want to review their data prior to using their coupling.
The past 22 years of my working life have been taken up in designing, building, and testing new lightweight components for marine hydraulics. Whilst these components had to be lightweight, they still had to pass all the Marine Survey testing and accreditation, and had to be reliable in service.
The universal joint in this coupling just plain looks like it is wrongly applied. It is the primary connection between tug and van, and in the event of a failure, only your safety chains and your skill as a driver to rely on averting a potential disaster.
Perhaps I need to think outside the box more, but at this stage it is a no go for me.
Peter
PJK
Darrell
Uni joints do fail,, I've replaced a few years ago that failed,,, cars and trucks,,,, but on tailshafts and that is axial load at high revs/load
Darrell, I agree that conventional couplings do break, be it the ball shaft, or the coupling, or how the coupling has been mounted.
Also don't dispute that there has to be a better system. One that immediately comes to mind is the Military type couplings, but they are noisy in use and have some fore and aft slop, so caravan owners probably would not like them.
I have seen the results of U-joint failures - automotive, agricultural, and industrial.
One of the most common causes of U-joint failure is due to not making sufficient allowance for shaft increase in length due to thermal expansion. The thermal expansion puts an axial load on the joint - exactly the type of load that this coupling will experience. (That is axial load caused by towing, not caused by thermal expansion.)
I just hope the manufacturers have done their homework.
Regards
Peter
PJK
Thanks Darrell,
I am just waiting till my van is next out of storage, and it will get McHitched.
Mate we have fitted a McHitch auto to our brand new Paramount Vogue all up weight of 3.250 tons. It is the greatest thing since the invention of the wheel for hitching up and unhitching. People should not criticize unless they have tried it. Had a Hyland on the last van loved that hitch but the Mchitch is a new style and it works great.
-- Edited by nissanpete on Sunday 21st of September 2014 03:52:09 PM
just seeking any updates on personal use of the hitch.
Hey mate weve just joined the site looking at the mchitch and WDH whats your wdh and your tow tug weve got THE 2014 bt 50 SUPREME 2015 EXC
CHEERS