PullRite TT hitch questions Update Installed Pic's

OK pic dis not seem to come up so i'll try again.

My friend had one when he towed a race car with his Ford and also had a Lance camper in the bed at times. The torsion bars also hold the trailer straight to the hitch and the pivot is just behind the rear axles.

I can't help you with the forces. Not sure if anyone but pullrite can answer that.

Great hitch and you got a super price! Don't worry about force on rollers if they are in good shape. I had a full size Bronco with the Pull Rite back in the late '80s, pulled a 26' StarCraft TT from FL to AK 18K never a problem. You will (with practice) get into sites easier and amaze others because they really work. No sway at all even on my short wheel base because the pivot point is about at the rear axle, just like a fifth wheel. You will answer lots of questions from people about your funny hitch. Enjoy...BTW they were well over a grand in the late '80's. :) :)

You got yourself a steal and what is considered by many to be the best hitch money can buy.

If our member Ron Gratz comes by, I am sure he can give you the numbers you are looking for. In the meantime, you might want to give a good look at this thread by him that is stuck at the top of the forum. Some of the questions you asked may be answered in that threads first post.
Barney

Bendder wrote:
---What I would like to know is the downward force at the pin by the diff and also the forces on the bearing rollers? any help would be appreciated

Mark, welcome to Open Roads Forum.

You can get a good estimate of the downward force at the pin by using the following leverage equation:

Force * (61.5" + D) = TW * D or Force = TW * D / (61.5 + D)

where 61.5" = distance from pin to ball per your diagram,
D = distance, in inches, from ball to midpoint between TT's axles, and
TW = tongue weight.

The above equation assumes there is no significant vertical force exerted on the roller bearings.
It is my understanding that the WD bars should be adjusted to minimize this force.

For your information, this thread contains a wide-ranging discussion of the PullRite hitch (and a lot of other stuff).

This web page by ORF member, Steve Rankin, shows his installation process.

BTW, you did a great job on the PullRite diagram -- except the downward force on the ball (which you show as 1000#) is equal to the TW plus the downward pull exerted by the two lift chains minus the amount of load transferred to the TT's axles.
For your example the downward force on the ball might be approximately 1000+2000-200 = 2800#. (The 200# depends on "D" in the above equation.)
The upward force exerted on the hitch head via the front ends of the WD bars would be 2000#.
The net force exerted on the hitch head, and transmitted to the pin, would be about 800#, if we ignore the weight of the drawbar which extends from hitch head to the pivot pin.

Ron

Thanks all for your reply's and yes I realize I got a great steal of a price. I have been cruising the internet adds for some time looking for one of these. I traveled 1000km return to go get thisso even including $180 of gas it's still a great deal. The last prices I saw for one were about $1800 CDN Looking forward to getting itall up under the truck. I think I will relocate my truck spare to under the TT along with the TT spare (I hate the Spare way out back on the bumper) Truck onlu gets usd to pull the TT and boat anyway. I`ll take my chances the odd time I do something else with the truck (not often)

Ron, thanks for the equasion for the forces. I had not thought about the forexerted by the WD bars down on the hitch ball but yes that would be true. From what I have read in the owners manual for the hitch (yes I did get everything the owner had from the time of purchase even a sales broshure) I will need to adjust the WD bars untill there is just a slight force on the lower bearings. I`ll need to take some time to set everything up but I don't mind. I will try to document everything for all to read. I am looking forward to a trip to the scale also to see any differences that will result.

I`ll keep you all posted

Update. Well I got the PullRite all installed up under the truck and set the ball height to what my pervious hitch was at as a starting point. Here are some pics

Old vs PullRite. Had to move up to the next hole to align the ball.

Clearance under old hitch

Clearance under PullRite

Clearance under bearing rail 12``

Clearance under swing arm

Max turn to passengers side


Hope you can see these pics.

next weekend will be the first pull so I will report back then on how it goes. I will also plan a trip to the scales and check old vs the PullRite to see what the differences in weight distribution really are when everything is loaded up.

Mark

So I had the TT out for a test run last night (sorry for the dark pic's I work from sun up to sun down) It was very smooth... Odly so in fact. I needed to play with the WD bars a fair bit to get the ride set properly where there was just a small load on the bottom bearings ( if you bounce on the tongue you can turn them) I followed all the directions in the Pullite manual that came with the hitch. I am looking forward to a trip to the scales because the weight does not seem to be distributed the same. I had a 2" drop to the back of my truck at the wheel wells prior to this install with my old hitch with 1400LB WD bars and the front would drop 1/4". With the new PullRite the back of the truck drops only 1" and no change at the front. I find this odd as the weights have not changed The only thing I can account it to is the tongue length being longer?

As you can see this turns much further that my conventional hitch. In the picture I was not up against the stop (still had another 8" of rail to go, so I think about 20*) The TT was completly free and away from the side of the TV though. It does take more space in the turns but that's just a habit thing. Need to find a curly cord for the lights instead of just an straight extension.





Mark

Moderator edit to re-size pictures to forum limit of 640px maximum width.

Bendder wrote:
I had a 2" drop to the back of my truck at the wheel wells prior to this install with my old hitch with 1400LB WD bars and the front would drop 1/4". With the new PullRite the back of the truck drops only 1" and no change at the front. I find this odd as the weights have not changed The only thing I can account it to is the tongue length being longer?

Yes, you have it correct. The leverage is different. With the tow ball being approx 60 to 65" the rear axle on a conventional hitch, the Pull rite may only be 12" behind the rear axle. And the fact the Pull rite makes the TT tongue almost 65 to 70" longer so the weight at the pivot pin under the truck is less weight the truck has to bear from the TT.

Of course the actual weight of the Pull rite frame under the truck does add weight back onto the truck.

Enjoy your new hitch. The principal is the best out there IMHO for for mitigating trail sway effects from a TT. I wish they would of took me up on making a heavier rated dead weight receiver on the big 2,000# unit as I may have had one by now. As with everything, there are trade offs.

John

Yes its too bad the receiver they have is only rated at 3500lbs. I am luck that on my newer F150 that I could fit the hitch below my factory hitch so I don't loose out on anything other than a bit of ground clearance.