Hensley Bump = ProPride Bump?

[Secguru]

Dear Friends:
- I have made up my mind to buy a ProPride Hitch (new hitch by Jim Hensley). I like to do a lot of research before buying and have found some threads on the Hensley Bump. The most descriptive is on Good Sam Open Roads Forum Good Sam ERS Open Roads Forum: Travel Trailers: Dynamics of the Hensley 'BUMP'?
- The bump can be dangerous to say the least and seems to defy Hensley's claim that the trailer cannot control the TV when equipped with a Hensley hitch. Seems that it most certainly can with disastrous results if on wet roads when turning if brakes are not applied soon enough.
- My question is: Has ProPride solved the Hensley Bump with its new design, or is it something to be aware of?

Be kind to everyone,
Secguru

[BeBop]

I have no experience with the ProPride hitch.

The Hensley "bump" disappears when your controller is properly adjusted for braking effort.

[adonh]

I have had a HA for almost 10 years and have traveled extensively in all types weather and road conditions. I have never had a "Hensley Bump". For a number of years I used the Jordan brake controler and then switched to the P3 when I installed the Kodiak disk brakes. Both provide smooth stopping and no bump.

Don

[loudruff]

http://www.airforums.com/forums/f464...-new-post.html

This is a newer thread that you may want to read. Thanks to 2air for starting it. It is a thread that is for those that are already PP users and their discussions of the set up and use of the PP.

[crispyboy]

I have experienced two different scenarios with my HAHA. When I first started using it I received the "bump" in normal stopping scenarios until I readjusted adjusted the brake controller. Problem solved.
The second scenario is when I had been towing for several hours and the last hour was over some rough road on I-65 in Alabama. I had to make a quick stop in traffic and noticed that the trailer tongue was going back and forth very rapidly. Later I noticed that the strut bar was not snug as it should have been.
I would contend that the physics of the HAHA and PP are identical and you could potentially receive a "bump" from either hitch.

[2airishuman]

Originally Posted by Secguru

...The bump can be dangerous to say the least..

the bump is related to IMPROPERLY setting up the brake controller or INadequate trayla brakes.

as has been previously stated many times here.

MOST of the online chatter about this issue is from folks who do NOT own a 4bar designed hitch.

neither design (haha or pp) as changed this issue.

it's about proper brake controller adjustment and VERY simple to avoid.

IF/when u start using one of these gizmos,

it will be a lot clearer WHY it's not possible to eliminate IN the hitch design.
_________________

also it is NOT a sway related event.

and ANY trailer with poorly adjusted brakes can PUSH the tow vehicle...

even towing ON THE BALL can result in PUSH from the trailer, if the brakes or controller are inadequte.

but with conventional hitches or BALL towing, there will be NO WARNING that push is happening.

so another way to look at the issue with a pp or haha is ...

ANY bump/nudge or sensation of trailer PUSH is an early warning to get the brakes and controller dialed in better.

REGARDLESS of towing apparatus brand or design.
______________

typically the product bashers, or noobs' who have no experience OR are promoting other hitches...

CHATTER and multiply the posts ON bump...

i hope that isn't the direction or goal here.

cheers
2air'

[slowmover]

Some of that same group mentioned has now convinced themselves that a PULLRITE is the only "safe hitch" (my words).

Agreed that hitch setup/brake operation/brake controller are the places to solve the "problem".

And that only testing the rig under the controlled conditions of a giant empty parking lot, an observer; wet & dry, etc (gravelled lot) can make for predictability (once vehicle weights have been verified/hitch rigging perfected) as predictability is a function of experience. We have to know the limits. And then discount for driver inattentiveness.

[Secguru]

Dear Friends:

Thanks so much for all the great help on this. Additionally, after talking about this with a friend who used to drive big-rigs, he reiterated 2air's comment that a trailer with any hitch can exert lateral force into the tow vehicle if the trailer brakes are set improperly (witness big-rig jack-knifes). I also note 2air's excellent thread on PP setup. Thanks very much for that excellent thread.

This ties into my other thread on brake controllers (P3/TruControl/Brakesmart). I understand better why Sean Woodruff prefers the Brakesmart. The most important thing about a brake controller seems to be that it engages the trailer brakes before the truck brakes and that braking is proprotional to the TV braking. This especially applies to exhaust braking where trailer push can creep up on you. I had this disconcerting experience several times with my old Freightliner FL60 towing a 37 foot fiver, hence my concern about the Hensley bump.

Be kind to everyone,
Secguru

[RossFam05BH]

Originally Posted by 2airishuman

the bump is related to IMPROPERLY setting up the brake controller or INadequate trayla brakes

Given our experience, the above statement is partially correct. We first used our 2003 GMC 2500HD CC to tow our 2005 30' bunkhouse, all connected through a Hensley. Even with the Prodigy controller set to boost 3, moderate braking in a turn would sometimes result in the "bump". The feeling we experienced was that the trailer seem to dive under the truck and lift the rear end. Rear wheel traction would be lost and the trailer-truck combo would "bump". The longer the trip, i.e. the more weight in the bed of the truck, the fewer instances of "bump". When I say fewer instances, I mean twice or three times over 5000 miles. It wasn't that hard to deal with.

Now we tow with a 2002 Ford Excursion and have used it for over 10000 miles. Still using a Hensley, same controller (but set at boost 1), and we have yet to experience the bump. The only difference is that we use a 2" rise stinger with the Excursion rather than a 6" drop with the GMC truck. Our interpretation is that the trailer used to lift the back wheels of the GMC truck, but now the trailer pushes down on the wheels of the Excusion during braking eliminating any sensation of "bump". Anecdotal evidence at best, but the change of tow vehicles and stinger made all of the difference.

[2airishuman]

hi rossfam'...

thanks for posting.

your description of events is excellent and very clearly conveys what you felt/FEEL while towing.

but imo the INTERPRETATION is off a tad.

i'm no expert, but will try to reframe the feedback you've gotten while towing with a different perspective ....

WARNING

these insane interpretations may B totally OFF or based on INCORRECT knowledge of your equipment, driving experience and...

may violate every known fact related 2 brakes, trailers, driving and phissss icks.

Originally Posted by RossFam05BH

...We first used our 2003 GMC 2500HD CC to tow our 2005 30' bunkhouse...
with the Prodigy controller set to boost 3, moderate braking in a turn would sometimes result in the "bump"...

this statement suggests even at 3 the controller was set TOO LOW or the trailer brakes were NOT up to the task.

there should be NO BUMP once the variables are dialed in.
_____________

the BH model is one of the heaviest modern streams built on 2 axles AND the safari chassis.

which means it came with drum brakes not discs.

drums have a long record of reliable service and are widely used on trailers...

but drums engage, modulate and respond to HEATING differently than discs...

and FADE is a common experience with drum brakes.

so IF one spent the time to properly DIAL in the controller so that the trailer brakes 'drag' back a little on the tow vehicle....

it's possible THAT relationship would CHANGE with heat/high use or in long STEEP downhill locations...

Originally Posted by RossFam05BH

...Now we tow with a 2002 Ford Excursion...same controller (but set at boost 1), and we have yet to experience the bump...

again it's NOT the controller setting that matters but WHAT HAPPENS at a given setting.

so IF the trailer is down 'dragging' back on the exc' a little, it's properly adjusted and no bump will happen.

Originally Posted by RossFam05BH

...The only difference is that we use a 2" rise stinger with the Excursion rather than a 6" drop with the GMC truck...

actually that is NOT the only difference and may not be the most important difference.

because the MAJOR difference imo is the BRAKES on the gmc truck vs the ford exc'....

UNLESS the rotors and calipers have been UPGRADED on the exc', they are LESSER brakes with LONGER stopping distance than the 2003 gmc.

the oem exc' brakes are also more prone to FADE than the gmc' bits from 2003.

you can find a LOT of info on this issue and perhaps the exc' already has UPgraded brakes,

but if not, THAT ISSUE is the major difference in your rig/combo...

because NOW the tow vehicle brakes are some what LESS powerful and more prone to FADE,

which translates to the TV brakes, MATCHING the trailer brakes better.

this observation is NOT a criticism of EITHER vehicle or the trailer, just an example of comparable parts that work together better.

it could also be total nonsense
_____________

i've NOT seen this written, or discussed it with rich, so it may NOT be true...

but richL upgraded his bunkhouse to discs brakes, while towing with an armada.

i suspect that the armada had exceptionally LARGE/responsive brakes, that OVER whelmed the drums on the trailer...

so that even with LOTS of adjustment and careful attention to the details...

the tow vehicle was doing MUCH of the stopping, and resulting in PUSH on occasion.

and INCREASED WEAR on the armada pads/rotors.

we'd have to check with rich on this,

i'm just guessing but suspect that AFTER adding the DISC brakes to the bunkhouse...

the 2 vehicles were BETTER matched for braking which equals NO PUSH...

Originally Posted by RossFam05BH

...Our interpretation is that the trailer used to lift the back wheels of the GMC truck, but now the trailer pushes down on the wheels of the Excusion during braking eliminating any sensation of "bump"...

you may be CORRECT about lift vs dive and the drop bars influence on this...

but PUSH is PUSH and if the trailer is STILL PUSHING the tow vehicle,

THAT issue needs to be corrected...

so MORE/faster/less fade braking is needed at the trailer end on your combo...

the trailer should NOT exert enough push or DIVE to squat the tv drive axle.

unless the TONGUE MASS is OVER the w/d bar rating and the tv rear spring stack is TOO SOFT...

it's always somethin'...

cheers
2air'

[rluhr]

Originally Posted by 2airishuman

i've NOT seen this written, or discussed it with rich, so it may NOT be true...

but richL upgraded his bunkhouse to discs brakes, while towing with an armada.

i suspect that the armada had exceptionally LARGE/responsive brakes, that OVER whelmed the drums on the trailer...

so that even with LOTS of adjustment and careful attention to the details...

the tow vehicle was doing MUCH of the stopping, and resulting in PUSH on occasion.

and INCREASED WEAR on the armada pads/rotors.

we'd have to check with rich on this,

i'm just guessing but suspect that AFTER adding the DISC brakes to the bunkhouse...

the 2 vehicles were BETTER matched for braking which equals NO PUSH...

2air, you are right about the "push" when were towing with drum brakes and a Reese hitch. I hated it. We never could get the Prodigy brake controller adjusted exactly right for all circumstance. Worse, we got pushed right into an intersection once. That experience pushed me right to disc brakes!

We had a superb and bump-free experience with the Armada after we switched to disc brakes. David Tidmore of Roger Williams Airstream did our initial disc brake setup on the Safari 30 bunkhouse/ Nissan Armada combination, and he installed the Hensley at the same time. He set the Prodigy at about 6 volts with boost level 3. This worked very well and we never experienced a bump in about 50k miles of towing over the next two years. Thanks to the self-adjusting nature of disc brakes, we also never had to touch the Prodigy again.

David was a big believer in making the disc-brake-equipped trailer do the work on braking. This was not only to eliminate the Hensley "bump" but also because it prevents the possibility of the trailer pushing the truck. With discs, you have a lot of excess braking capacity so this is easy to set up. This is why I am a big advocate of disc brakes and proper weight distribution -- if you've got those two factors right, you probably won't be saying "the trailer pushed my truck off the road!" later...

The disc/Hensley combination worked excellently for us. The proof of how aggressively the trailer was leading the truck in braking came when I sold the Armada last June. The Armada had 80,000 miles on it, of which I estimate 70-80% was towing, and it still had the ORIGINAL factory brake pads! I had the brakes checked at the Nissan dealer as a condition of sale for the new owner, and they were still within normal wear tolerances, e.g., no replacement pads needed yet ... whereas, we had replaced the pads on the Safari three times in the same time period!

When we switched tow vehicles and visited Can-Am RV, Andy Thomson adjusted the Prodigy again. His theory was that he likes all possible braking power to be available in case of an emergency, so he set our Prodigy to 12 volts and boost level 1. The new tow vehicle has brakes that are as good or better than the Armada's, and after 10,000 miles of towing I can say that I am happy with the performance -- and still, no bump.

So in my experience, avoiding the "bump" is a matter of proper brake controller adjustment. As you are suggesting, proper adjustment can be difficult if you have weak brakes (relative to the truck) on a heavy trailer.

[ROBERT CROSS]

No "bump" here....

Just take the time every Spring to install and set the measurements properly.

Three seasons and no bump so far.

[2airishuman]

thanks rich for the details...

accurate info is occasionally a goal here.

Originally Posted by rluhr

... We did, however, experience quite a bit of "push" with drums and a Reese hitch, and I hated it. Got pushed right into an intersection once...

so was the above with the BH or vintage thunder?

Originally Posted by rluhr

...We had a superb and bump-free experience with the Armada after we switched to disc brakes... He set the Prodigy at about 6 volts with boost level 3....
David was a big believer in making the disc-brake-equipped trailer do the work on braking....This worked excellent for us...The Armada had 80,000 miles on it, of which I estimate 70-80% was towing, and it still had the ORIGINAL factory brake pads!

...When we switched tow vehicles... so he set our Prodigy to 12 volts and boost level 1...I am happy with the performance -- and still, no bump.

So in my experience, avoiding the "bump" is a matter of proper brake controller adjustment.

yeah, my truck is still on the oem pads at over 70,000 miles of towing.

and the trailer brake pads were changed after 50,000 miles of travel "just because"...

with more than 80% of the original pad still present.

but i regularly drag a foot to slow the rig, like fred did in the old daze.

your 2 EXPERTs who set up the controller very differently, but with equally good results and NO BUMP...

help demonstrate there are often multiple roads to the same great destination.

cheers
2air'

[rluhr]

Originally Posted by 2airishuman

so was the above with the BH or vintage thunder?

It was the Bunkhouse. I never felt the 12" drum brakes were adequate for a trailer with a GVWR of 8400#. (I have spoken to many owners of 30 to 34 footers with drums who feel they are fine, so I know not everyone agrees with me on this one.) But even at 7200# or so, which is about what we weighed when this incident occurred, I could feel brake fade and pushing from the trailer. Given that we were full-timing, I felt the brake performance was unacceptable. If we'd had a Hensley at that time I'm sure we would have had "bump" complaints.

I don't mean to hijack this into a disc vs.drums thread, because there's been enough of that on other threads. My point is only that 2air is right on, when he says any "push" is bad. Whatever the cause, it needs to be fixed ASAP. If you can fix it with the drum brakes you have, that's great. And thank your Hensley/Pro-Pride hitch for letting you know!

Also, my apologies to 2air. I edited my post three times right after I wrote it, to correct some points, and he responded to an early draft. My first draft said he was wrong, but upon re-reading his post I realized I had misunderstood his comments... in fact I think he's right on target with his analysis and advice.

[2airishuman]

Originally Posted by rluhr

...Also, my apologies...

no need rich.

getting the original first person reports is the prime objective.

learning happens and better understanding matters more 4 me than being right or wrong.

victory is fleeting but SCARS last 4ever!

good stuff really !

cheers
2air

on edit, the OP has another recent thread that may be useful,

especially for rossfam' or others being PUSHED or BUMPED in the curves...

http://www.airforums.com/forums/f439...art-58070.html

and the report that marshall rog' experienced PAIN is all the more reason to read it....

[Secguru]

Thanks both to 2air who always has something worthwhile to say and also to rluhr who did not hijack the post but added a very valuable extra dimension to it. I have also been thinking about changing my brakes to disk. I noted that there are several good posts on that topic. For those interested in this topic (including me), one such post is: http://www.airforums.com/forums/f206...kes-57501.html

Be kind to everyone,
Secguru

[Ben4762]

It is possible to experience the Hensley bump even if your brake controller is set properly. I usually downshift my transmission when going down a steep grade and sometimes there is no need to apply brakes. The travel trailer will be free wheeling and the Hensley will bump. This could create some handling problems if it happened on a curve in the road.

[2airishuman]

ben...

DOWNSHIFTing to slow, IN ANY CURVE is an issue while towing.

even with "on the BALL towing" the trailer will still PUSH forward.

IF this happens while using a haha it's a signal to NOT do that again.

1. SLOW (brake/shift) before the curve
2. TURN (without braking or shifting) in the curve
3. ACCELERATE (or SLOW more) after the curve

downshifting or using an EXHAUST brake can be a problem towing with ANY hitch...

IF the speed, grade, curve or deceleration CHANGE is significant.

bump = WARNING to do something different.

[Ben4762]

Originally Posted by 2airishuman

ben...

DOWNSHIFTing to slow, IN ANY CURVE is an issue while towing.

even with "on the BALL towing" the trailer will still PUSH forward.

IF this happens while using a haha it's a signal to NOT do that again.

1. SLOW (brake/shift) before the curve
2. TURN (without braking or shifting) in the curve
3. ACCELERATE (or SLOW more) after the curve

downshifting or using an EXHAUST brake can be a problem towing with ANY hitch...

IF the speed, grade, curve or deceleration CHANGE is significant.

bump = WARNING to do something different.

I think you missed the point I was trying to make in my post. The Hensley can bump on a straight away going down hill while using the transmission for braking. If it bumps in a curve it can cause handling problems. Some people with new Hensley's may not be aware of this. I don't brake in a curve. I've owned this hitch for 10 years.

[2airishuman]

and it appears you missed THE point...

ANY hitch can push on a straight way going down hill while using the transmission for braking. If it pushes in a curve it can cause handling problems.

EVERYONE towing needs to be aware of this.

and only the haha/pp give a CLUE that PUSH is happening.

cheers
2air'