Propride P3 hitch installs

This is the story to two installations of ProPride’s P3 hitch system. We have a 26 foot travel trailer on an F150 truck and our daughter’s family has a 35 TT on a E3500 van. We’ve not been impressed with hitches with friction based damping, so after a lot of research, we chose the quite expensive ProPride P3.

If you’ve ever towed a large trailer, you will likely be familiar with this experience: You are driving down the interstate, in the right lane and a large semi-trailer begins to pass you on your left. The “bow wave” from the truck starts to push on the trailer – shoving it to the right. That right force, pushes to the right on the back of your truck – which makes it want to turn LEFT – right into the approaching semi. So, your natural tendency is to turn slightly to the right to correct. Just about the time you get straightened, the bow wave is now pushing on your truck – making it move to the right. Depending on how much faster the truck is moving, the direction of the wind and how much you tend to “correct”, this dance can get somewhat exciting. Additionally, when there is a strong side wind, then overpasses and large trucks on two lane roads, etc, can also give you quite a yank.

The P3 uses a trapezoidal box to connect between the truck and trailer – when one side connected to the truck and the opposite side to the trailer. It has the effect of projecting the connection point forward to near the axle of the truck. I prefer to think of it a different way. A right push on the trailer pulls on the right side of the trapezoid, translating into a clockwise force on the truck so it doesn’t make the truck turn left.

So, its not that you don’t feel any push with the P3 – you do. But when a semi passes – you feel a little push away. That is all. Its quite predictable and most time you don’t fee l like there is any need to “correct”.

Friction based dampers only limit the amount of sway – the P3 translates the force differently, thus eliminating sway before it starts.

P3 on Blue & Tumbleweed
P3 on Blue & Tumbleweed

We ordered two P3s and shipped them

P3 on Joy and the van
P3 on Joy and the van

to the same address, which

saved us a bit on the shipping. We decided to do our trailer first in hopes of working out any installation confusion the first day. Propride says the hitches can be installed in about two hours – but the average from blogs I’ve read seems more like 3-4. For us, it was more like 5-6. Its not because we don’t know which end of a wrench to hold, but rather because the instructions could be a bit clearer (because no two trailers are alike) and because we encountered problems, especially on the second trailer.

P3 Side View
P3 Side View

I’m going to include specific instruction “additions” below, so these descriptions will simplified.

First part to install is the adjustable hitch bar. Since receivers (car end) and the trailer hitch are often at different levels, the hitch bar is made in two parts, with a series of holes. The instructions have you measure the height of your receiver box and the top of the trailer ball mount with the trailer set level. Then a series of “if this, do that” instructions guide you which parts to put right side up or up side down and which holes to mate to bolt it all together.  They are confusing. Some simple pictures would help a lot.

So following the instructions – the F150 said to have the adjustable hitch straight across. The Van had the trailer end ½ inch higher. Neither of these turned out to be right. We tried a number of combinations over several days. I eventually went back to my instructions for a different weight distribution hitch. Those instructions had me take a measurement of the fender height, front and back, with the tow vehicle unloaded, loaded-no-weight-distribution and loaded with weight distribution. That way you get some measure of whether you’ve transferred weight up to the front axles. ALSO, just important, is to measure whether the trailer has been returned to LEVEL when the Weight Distribution is added in.

Simply put, you need to deal with the fact that when the trailer is added to your tow, the rear of the tow will go down. When figuring the adjustable hitch bar, you need to take this into account or your trailer will end up lower in front.

On the F150, we left the hitch bar ends even and added in enough washers to get 8 degrees of down tilt to distribute more weight to the front axle. The trailer isn’t quite level yet, so I may do one more adjustment on this. On the van, we raised the trailer side 2 holes and added one washer to get 6 degrees of tilt. We moved measurable weight to the front axle and the trailer is now dead level.

P3 Jack location. I actually moved mine back just a bit from this location to better clear the LP tank cover.
P3 Jack location. I actually moved mine back just a bit from this location to better clear the LP tank cover.

After the hitch bar, comes the jack posts. We had to remove the propane tanks and the tank shelf. Fortunately, the shelf sits on a separate bracket so we’d be able to move the shelf forward a bit when we put it back. The jacks slide over the trailer frame – and in our case since we have box frames, there is a steel spacer that went in back, plus a set bolt that locks each jack in place. Finally, there is a large U-bolt that goes around the frame to hold the jack down.   Instructions say these go 26 inches back from the center of the ball hitch – but that can extend up to 27 ½ most of which was required on both trailers. The big problem was these jacks are designed for trailers that use just under 2 inch box frame members. On the first trailer, they went in fine. On the second one, the frame was just over 2 inches wide. The result was an hour of grinding on the spacers and test fitting. Eventually they barely fit on the frame. Because of this, I suggest a test fit of your jacks FIRST THING, because by the time you might find out yours doesn’t fit, you are well past the point of no return.

Then the frame bracket goes on – a heavy bracket that bolts across the trailer frame just ahead of the jacks. The Yoke (which bolts to the hitch head) reaches back to this frame and both allows the head to tip, but also holds the head straight with respect to the trailer. More U-bolts. We carefully measured this bracket, both side to side and distance on each side from the center of the ball hitch. Then again AFTER the Yoke is installed to tweak the distance.

Then the main hitch unit is lifted into place and locked into the trailer ball mount.

The Yoke is added to the main hitch unit and placed into the slot in the frame bracket and locked into place. Then the weight distribution bars are connected to the jacks and plugged into the main hitch head.   Once everything is bolted then torque to specs (you need a 250 pound rated torque wrench).

P3 trapezoid
P3 trapezoid

Then the tow vehicle can be backed into the hitch – which is a bit more complicated since you aren’t just parking a ball under a head – this bitch bar has to be the right angle (in two directions) and height in order to slide in enough to lock in place.

Finally re-measure the fender height, front and rear of the tow vehicle before anything is connected. Then measure with the trailer weight added to the tow, to see how much the front lifts (and rear drops). Then adjust spring jacks and measure again.

Basically the adjustment goes like this.

Look at how much the front of the tow goes up with the trailer weight on. You want to eliminate as much as half of that rise.

You then raise the trailer using its jack to make it easier to adjust the P3 spring jacks and run both jacks up to about 6 inches. Then lower the trailer till all the weight is back on the spring bars. Measure the front fender. If you’ve not take enough of the rise out – you can raise the jacks a bit more, but according to Sean, you don’t get much lift past 7 inches, and that is what we found. Not a lot of change after 6 inches.

If the trailer isn’t high enough – there are two things that may help.   One change the offset between the tow and the trailer in the hitch bar – raise the trailer side. Two, especially if you’ve not transferred enough weight to the front of the tow vehicle, change the angle in the hitch bar – add a washer, to angle down the trailer side. This allows more shifting of weight on the tow vehicle while also bringing up the trailer side.

By all means, get your tow vehicle weighed and the two + trailer weighed. This will show you how much weight is added to each axle AND give you an approximation for tongue weight and whether your trailer is overweight as well. I bought a tongue weight scale from Propride – but you can extract pretty good numbers for the two trips to the scale. We used a local Cat scale. The process is pretty simple. Just pull on with your front, rear and trailer axles on each of the three squares. Push the botton and give the guy a number. Any number….. 77564. When the operator says, OK, drive to the office, go in – give them the number. Pay $11. When you come back, tell them reweigh and give them the same number – wait for OK, drive to office. Pay $2.   We took our tow vehicle first, then came back with the tow+trailer rig.  The difference between the two total weights, is the weight of the trailer.  Subtract the weight on the trailer axles from the total weight of the trailer and that should be the tongue weight.  Or subtract the weight of the truck alone from the weight of the truck when trailer is on and that should also be approximately tongue weight.  Since you are distributing weight to both axles of the tow, its not exactly the same is just putting a scale under the trailer ball.

Words of wisdom – the jacks can go back to 27 ½ inches. This helps a lot on the propane bottles on some trailers. You will still have to move them (the shelf) forward a bit.  We had to move the brake breakaway switch on one trailer.

The frame bar is supposed to be 22 inches – on both trailers it ended up closer to 21.

Two people are needed to lift the heavier pieces and the Yoke because lining up both sides at the same time is difficult with even two people.

The hitch bar instructions are easy to get lost in the A, B, C, D sections. Have someone else read and agree with you before you start using the 250 pound torque wrench.  Draw a picture, or two or three or four.

Measure your frame width carefully if it’s a box frame. Make sure it is just under 2 inches – or that your jacks are just larger (with shim) than the box width. Or do a test fit. After you’ve take off your old hitch and started an install is not the time to find out that your jacks are not going to fit without a lot of grinding on the shims.

P3 receiver opening
P3 receiver opening

If your trailer jack has a foot-pad attached – make sure you either remove it – or run it up higher than the spring bars. You can move the head around when its not attached to the tow vehicle and make sure it clears your jack, but it will not clear the foot unless the foot is fully above the spring arms.

Both our trailers are Forest River (Flagstaff and Rockwood). Both have the safety chains connected to a single V-shaped bar welded to the front bottom of the trailer. The Propride head hits the chains coming off this bar when near near fully turned. I’m going to have to re-position this mount to the frame sides. (Some states require TWO separate safety chain mounts – this is a FAIL on all accounts on Forest River).

You will most likely need chain, safety brake cable and electrical extensions. The 35 ft TT happened to have a long enough electrical cable, but everything else on both trailers needed to be extended.

 

 

The test….

We took the trailers on a couple day, excursion to test out the hitches. Driving, they were great. No being pulled into a semi as it passed. You still know you are being passed – and I think the more we drove, the more we noticed the smaller push from the big rigs. We did have an “issue” getting our brakes adjusted. The “bump”, when stopping or pulling away is in indication that the trailer brakes aren’t set quite high enough. If the trailer is pushing the tow vehicle, the trapezoid can shift to one side, especially if stopping on a slight turn.  We have not done the “20 mph, see if the brakes lock up” test on either trailer, but we may still have to do that to make sure we don’t have the brakes set too high.

Because both trailers had extra hitch down angle, it also made it a little more tricky hitching up and down. I kept my level handy and put it on the bar, and the head when hooking up as an easy way to see if we had the head at the right angle.   I’m thinking a couple of stick on, round bubble levels might be a good thing.

When disconnecting, the instructions say watch for the ball mount to move to know when you’ve lowered to the right amount. That almost never worked. We kept a tape measure handy and did a quick measurement of the height of the hitch bar top at the receiver. That would get us close. Then, after everything is disconnected – have the driver pull forward just one inch. Watching the bar go up or down then indicated the direction the trailer needed to go so the hitch could cleanly pull out.  Then pull forward a few more inches to double-check. Adjust the trailer jack if need be and then move all the way out.  Phones, radios or clear hand signals is important.

P3 cover side view
P3 cover side view

Hitching up is pretty straight forward, so long as someone can go straight backward. A rearview camera helps a lot.   Depending on the slope the tow is parked on vs the trailer, it might be necessary to adjust the spring jacks to get the angle of the head to match the hitch bar enough to slide in.

I ordered some waterproof material to make two hitch covers. There was some trial and error involved, but eventually I made a pair of covers including matching jack covers (entirely unnecessary, but cool looking just the same).

 

P3 new chain mounting
P3 new chain mounting
P3 chain hit
P3 chain hit

On the first trip I noticed a dent in the rim of the P3.  On closer examination, I discovered that the chain and chain mount bar on the trailer were being hit by the P3.  I never liked how Forest River attached the chains.  They are proof chains, but they are attached by heating, bending and welding a single steel rod to the bottom of the trailer.  I’ve read some states require separate mount points for each of two safety chains.  So, we bought hardware and new chains and proceeded to move the attachment points.  When I was using the sawsall to cut off the rod – the first side took forever to cut, meaning it was hardened steel.  The other side of the same rod cut like butter – meaning it wasn’ t hardened at all.  The ends of the frame boxes had thin steel welded across which had to be cut off so we could get nuts and washers inside.  There was a huge hornet nest inside my frame, which

P3 chain damage, zerk fitting
P3 chain damage, zerk fitting

thankfully was vacant at the time.  After putting it all together, I used large crack foam to fill up the open frame ends.

Don’t forget to add a bit of grease ever few thousand miles.

mgg

 

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