Diminished Hensley Performance?

[boondockdad]

De-winterized the 'stream, loaded her up, and headed south.

Until this trip, towing with the Hensley has always been effortless and totally predictable. No sway- at all.

Over the last 1200 miles, it's behaved like a completely different rig.

SWAY! Getting 'bow-wave' push from passing semi's.
Experiencing a back and forth wiggle, while underway, almost like the trailer wagging the truck (I've NEVER experienced THAT before- even when I towed a 2005 31' Classic with a seriously under-rated RAM1500 AND friction sway-bar).

Couple of hard braking incidences, not only got the 'hensley-bump', but severe pull as well. Braking hard with ONLY the trailer did not reproduce.

Since I picked up my 'stream new in October 2007, I've had to bleed the brake system every time I pulled it out of storage. J/C has looked at it twice, and said there were 'no problems'. Actibrake (last year), said having to bleed the system every season is not normal.

Well, it needs to be bled, again- getting slightly delayed brake response, except when I 'prime' it...

Here's something that I noticed: watching the back-up camera, the hensley did almost no 'pivoting' at all. In the past (with perfect towing performance), I could see the box assembly pivoting constantly under the orange head- even while towing perfectly straight.

Struts are FIRM. The zerks are greased every 500 miles. I can freely pivot the box assembly when unhitched. Installed Hensley (factory new) April 2008. Has about 12,000 miles on it. I have not stored or covered over winter. ??

Two items to consider:
1. The 'burb was getting some slight 'wander' at highway speed (without trailer). Truck shop said front-end looked OK, toe was "way out" (don't have spec sheet).
2. Noticed 'wander' AFTER I installed 4 new Michelin LTX AT2 (This is the first time I've towed with the new tires)

Trailer Marathons at 65psi
Truck Michelins at 80psi

TBTG, I arrived without incident... but tired and stressed like I was 'white knuckling' it the whole way...

argh.

Any input would be appreciated (or a truck service shop recommendation)

[overlander63]

The Michelins have a softer sidewall than many other truck tires, and will squirm a bit more than you'd be used to. I don't think that would be enough to cause your troubles with the Hensley, though. Have you checked the bearings in the Hensley? If you have a bad bearing, it'll do some strange things. I'm sure you know they need to be repacked the same as the wheel bearings on the trailer, and do take automotive-type taper bearings. From it not "moving" while you are towing, it sounds like something is stuck. Is the centering latch perhaps somehow stuck, bent, or worn off?

[85MH325]

Joe... a couple of thoughts... obviously if the hitch is performing differently, have it checked. Have a suspension shop go through all of the rear axle/suspension assembly. It sounds like you might be getting some rear-axle steer with the 'burb... what you've described is almost exactly what my Excursion exhibited. The Excursion's problems were with a spring-stack that couldn't keep the axle centered under the truck. You may have worn bushings or some other suspension component that is allowing the axle to move. Terry's right... the tire sidewalls will also cause some movement that you're not used to, but at 80 psi you've probably done the best you can to minimize that.

The other thing to look at is whether you've loaded anything differently in the trailer that would cause a significant decrease in tongue weight.

These things are difficult to figure out sometimes, and you just have to systematically eliminate them one by one. If you're satisfied that you don't have any broken components on the hitch itself, start with the trailer loading ('cause it's the easiest to fix) then move to the 'Burb ('cause that's the most likely to have issues from wear) and work your way back. The hitch itself, while possible, is the least likely component to cause issues; it just may not be able to absorb those movements if it's not working properly. And you may find that there's several small issues that when combined, all contribute to what you're reporting.

Roger

[Wingeezer]

Joe,

If you manually pivot the black hitch box under the orange top section,does everything seem normal? If so, I wouldn't think there would be a problem with the main bearing assemblies.

Even though the struts seem firm, is there any indication that the shear bolts my have gone and the U-bolt assembly shifted somehow?


I've only had our Hensley a short while, so others will know far more than I, but I wonder if it is more likely a problem with you tow vehicle?

Brian

[RangerJay]

It makes sense that the items you mention as being possible contributors should be chased down - then the vehicle retested. Not sure about the tires, but braking and alignment should clearly be sorted out.

One additional item you might want to check out is the tracking of the trailer behind the tow vehicle. In our set-up I have noticed that if the trailer is not tracking exactly on-centre then hard straight-line braking will want to drag the back end of the vehicle to one side - not a comfortable feeling. Our tow vehicle has a short wheel-base so this may be a contributing factor. Once the hitch is adjusted to track perfectly centred behind the vehicle then a hard straight-line braking test does not reproduce this issue.

Our hitch gets removed every winter for cleaning, touch-up and storage so this "adjustment" has become an annual event after every re-installation. After installing as square as possible I head out for a long stretch of straight road and then do a series of adjustments by backing-off one strut and advancing the other by the same amount until I get it right.

Good Luck,



Jay

[SARGE/AF]

De-winterized the 'stream, loaded her up, and headed south. Until this trip, towing with the Hensley has always been effortless and totally predictable. No sway- at all. Over the last 1200 miles, it's behaved like a completely different rig. SWAY! Getting 'bow-wave' push from passing semi's. Experiencing a back and forth wiggle, while underway, almost like the trailer wagging the truck (I've NEVER experienced THAT before- even when I towed a 2005 31' Classic with a seriously under-rated RAM1500 AND friction sway-bar). Couple of hard braking incidences, not only got the 'hensley-bump', but severe pull as well. Braking hard with ONLY the trailer did not reproduce. Since I picked up my 'stream new in October 2007, I've had to bleed the brake system every time I pulled it out of storage. J/C has looked at it twice, and said there were 'no problems'. Actibrake (last year), said having to bleed the system every season is not normal. Well, it needs to be bled, again- getting slightly delayed brake response, except when I 'prime' it. Here's something that I noticed: watching the back-up camera, the hensley did almost no 'pivoting' at all. In the past (with perfect towing performance), I could see the box assembly pivoting constantly under the orange head- even while towing perfectly straight. Struts are FIRM. The zerks are greased every 500 miles. I can freely pivot the box assembly when unhitched. Installed Hensley (factory new) April 2008. Has about 12,000 miles on it. I have not stored or covered over winter. ?? Two items to consider: 1. The 'burb was getting some slight 'wander' at highway speed (without trailer). Truck shop said front-end looked OK, toe was "way out" (don't have spec sheet). 2. Noticed 'wander' AFTER I installed 4 new Michelin LTX AT2 (This is the first time I've towed with the new tires)
TBTG, I arrived without incident... but tired and stressed like I was 'white knuckling' it the whole way...
argh.

-------------------------------------------------------------------------------------
You describe the same issue I had when traveling. I just bought a 1997 34WB Legend that came with a Hensley (I am first time hensley owner/user).
I picked it up in Fla just above Tampa at Travelers Rest, and that few hours of travel to Ex29 I-95 GA, had both my hands cramping from holding onto the steering wheel. I have a 05 Excursion, the previous owner had a late 90's suburban which has a shorter wheel base than mine, may have something to do with it. Anyways the next morning I left from Flyng J and everytime a semi passed or any truck with a trailer including a fifth wheel I had to deal with the shove which made the trailer wiggle something fierce. I did make 2 adjustments to tighten it up and it seemed to help some but still had the bad sway, but I never had this sway issue with my other hitch and sway bars.
I also have a camera in the back and when pulling the hitch stays center, but when backing it does not. I also noticed it does move side to side alot which may attribute to the sway as well. The previous owner kept it greased and serviced.
Like I said though I have never owned one of these and know nothing about it, I am sure that those with experience on here will help with all the adjustments that I need to make before deciding to go back to my other hitch.

Sarge

[moosetags]

We've got over 50,000 miles of towing with the Hensley, and have not experienced anything like what you are describing. We have not experienced any sway, ever. Our Hensley is serial number 8332, and is about 4 years old. It's starting to look like crap, but it still works great.

We use the same Michelin LT on our 2500 Suburbans with the rears at 80 psi and the fronts at 70 psi.. I don't think that it's the tires. Our Suburbans have rear wheel steering (Quadrasteer) and this does not effect the towing stability.

I would start looking at a couple of things on the Hensley. Are the strut bars evenly adjusted absent of any play at the front end? Have either of the spring jack brackets shifted position? are the spring jacks evenly adjusted?

If all of these things are set up properly, I would give Hensley a call and discuss this with them. They have always been very helpful to me in the past.

Brian

[HiHoAgRV]

Since the only thing that has changed are the tires, I suspect they have caused your system to 'wander' to the dark side of towing...

Have you ever scaled your rig? I found that a small difference in TV front axle weight made my 34' tow like crap (I also have a Hensley). My setup tows fine with the WD bars cranked fairly tight even though I lost 130 lbs or so of front end weight, BUT if I loosen them just a little and the front of the truck lightens another 150 lbs or so we wander all over the place.

Good luck.

[Ag&Au]

Originally Posted by finalcutjoe

.........................

2. Noticed 'wander' AFTER I installed 4 new Michelin LTX AT2 (This is the first time I've towed with the new tires)


...............................

I noticed the same thing after I put LTX AT2s on my truck last year.

There was very noticeable and annoying wander. I had truck realigned, with perhaps slight improvement. Went to tire dealer and talked to him. He said it would go away as tires wore in. Sure enough it slowly improved and after about 2000 miles on the tires, it went away completely.

I did not tow anything during that time, but I think it would have affected the towing to be constantly correcting the steering.

Regards,

Ken

[sandlapper]

i I have run Michelins on my TV for years and would not have any other brand. They do have some gentle 'sway ' in them when they are new but improves after a few thousand miles. their deep tread depth and softer compounds probably contribute to it.

[Ag&Au]

Originally Posted by sandlapper

i I have run Michelins on my TV for years and would not have any other brand. They do have some gentle 'sway ' in them when they are new but improves after a few thousand miles. their deep tread depth and softer compounds probably contribute to it.

I have a great deal of experience using various Michelin tires and these LTX AT2s are the only ones that have adversely affected the handling characteristics. I am sure you are correct that it is the tall soft and bumpy tread pattern. As near as I can remember, they now drive about the same as the Goodyear less aggressive tread tires, I replaced.

However, I am not talking about gentle sway. When they were first new, if I glanced away for a second and looked backed, I could find myself heading for the ditch.

Regards,

Ken

[boondockdad]

Originally Posted by overlander63

The Michelins have a softer sidewall than many other truck tires, and will squirm a bit more than you'd be used to. I don't think that would be enough to cause your troubles with the Hensley, though. Have you checked the bearings in the Hensley? If you have a bad bearing, it'll do some strange things. I'm sure you know they need to be repacked the same as the wheel bearings on the trailer, and do take automotive-type taper bearings. From it not "moving" while you are towing, it sounds like something is stuck. Is the centering latch perhaps somehow stuck, bent, or worn off?

The box assembly pivots freely... I wondered if maybe it might not under load? Is that possible?
Do you know how often the bearings should be serviced?
I didn't notice anything about this in the docs...
My 2005 A/S, I repacked the wheel bearings every season... but the nevrlube bearings on my 2008 say to simply inspect for excessive play... replacement not required for 100k miles...

I'll check the center latch...

Tx

[boondockdad]

Originally Posted by 85MH325

Joe... a couple of thoughts... obviously if the hitch is performing differently, have it checked. Have a suspension shop go through all of the rear axle/suspension assembly. It sounds like you might be getting some rear-axle steer with the 'burb... what you've described is almost exactly what my Excursion exhibited. The Excursion's problems were with a spring-stack that couldn't keep the axle centered under the truck. You may have worn bushings or some other suspension component that is allowing the axle to move. Terry's right... the tire sidewalls will also cause some movement that you're not used to, but at 80 psi you've probably done the best you can to minimize that.

The other thing to look at is whether you've loaded anything differently in the trailer that would cause a significant decrease in tongue weight.

These things are difficult to figure out sometimes, and you just have to systematically eliminate them one by one. If you're satisfied that you don't have any broken components on the hitch itself, start with the trailer loading ('cause it's the easiest to fix) then move to the 'Burb ('cause that's the most likely to have issues from wear) and work your way back. The hitch itself, while possible, is the least likely component to cause issues; it just may not be able to absorb those movements if it's not working properly. And you may find that there's several small issues that when combined, all contribute to what you're reporting.

Roger

I didn't put the sherline under the tongue for this outing, but I didn't load anything different... famous last words, eh?

The 'burbs got 75k miles, with recommended 'heavy-duty use' maintenance. I would've expected to get more life out of the components (I'd estimate half that mileage is with the 10k trailer)

I'd like to have it looked at- by a COMPETENT mechanic... any recommendations?

[boondockdad]

Originally Posted by Wingeezer

Joe,

If you manually pivot the black hitch box under the orange top section,does everything seem normal? If so, I wouldn't think there would be a problem with the main bearing assemblies.

Even though the struts seem firm, is there any indication that the shear bolts my have gone and the U-bolt assembly shifted somehow?


I've only had our Hensley a short while, so others will know far more than I, but I wonder if it is more likely a problem with you tow vehicle?

Brian

Brian,

Nope.. strut tension was the first thing I checked after I experienced the sway... even my son in the back bench commented on the 'wiggle' and 'push'... very unsettling- and frustrating

Joe

[boondockdad]

Originally Posted by HiHoAgRV

Since the only thing that has changed are the tires, I suspect they have caused your system to 'wander' to the dark side of towing...

Have you ever scaled your rig? I found that a small difference in TV front axle weight made my 34' tow like crap (I also have a Hensley). My setup tows fine with the WD bars cranked fairly tight even though I lost 130 lbs or so of front end weight, BUT if I loosen them just a little and the front of the truck lightens another 150 lbs or so we wander all over the place.

Good luck.

I didn't scale the rig on this outing... I figured because I didn't do/load anything different, it wasn't necessary...

I'll be scaling it once we hook up (and may have learned my lesson...)

Tx

[boondockdad]

Originally Posted by w7ts

I noticed the same thing after I put LTX AT2s on my truck last year.

There was very noticeable and annoying wander. I had truck realigned, with perhaps slight improvement. Went to tire dealer and talked to him. He said it would go away as tires wore in. Sure enough it slowly improved and after about 2000 miles on the tires, it went away completely.

I did not tow anything during that time, but I think it would have affected the towing to be constantly correcting the steering.

Regards,

Ken

Ken,

My tire guy at Discount Tire told me same thing.. he actually tried to talk me out of the LTX AT2's because he said the 'aggressive tread' pattern would adversely affect towing performance...
Because I'm an expert in everything, I 'pishawed' him...

Tx,
Joe

[tintent]

It's probably your tires. I have a Ford Excursion V10 that towed beautifully until I changed tires. We had to stop while on the road to purchase new tires. The dealer sold me Firestone AT 265/75R-16. I couldn't keep the Airstream between the fenceposts. I tried adjusting our Reese hitch several times with no success. I, too, came home with white knuckles and wife with frizzy hair. I took the car to my local tire dealer, and he said the problem was the tires. He swapped out my AT (All Terrain) for HT (Highway Tread) of the same size. We've had no problem since the exchange. Hope this will help you with your problem.

[2airishuman]

hi fc'

bummer dude!

i don't have 1 of those fancy orange things but that doesn't seem to prevent OTHERS from giving advice so here's some...

start with the tires, many tires of/with SIMILAR tread designs are squirrel-y for 500-2000 miles.

i've almost taken back tires for this reason, but eventually they settled down and preformed fine.
_______

the bearings on the haha MAYBE need repacking every 4-6 years depending on use, water exposure and storage...

i think HIHO can give u some insight into how the grease ages...

(he might even have some pictures...)

but old dry grease isn't the cause of your symptoms.
________

IF the struts were loose OR a shear bolt failed, the front end of the TRAILER...

would be ALL OVER THE PLACE side2side...

it's a VERY dramatic experience and can definitely affect the tv rear end...

but you would SEE a very wiggly trailer back there.

(still a good idea to check struts and shear bolts, but that's not the problem either)

the HOLES on the hitch HEAD for the strut PINS can lengthen, so check them too...

but again that would cause LOTS of trailer wiggle, seen in the mirrors...
__________

the w/d bars BUSHINGS and grease zerks wear and can IMPEAD hitch performance...

but the typical symptoms are TURNING issues, not WIGGLE...

and the hitch head would NOT move freely as u've reported.
__________

most DEFINITELY if the w/d is NOT dialed in the truck will handle poorly....

LIGHT steering, the need to OVER correct for turns/wind and ruts are the clues...

but the burb BACK end should look LOW, the tires bulged, head lights UP and so on...
__________

so it's back to the tires, or leaf springs or shocks or rear axle on the tv...

are u SURE the tires are at 75-80 psi?

check all the normal stuff on the burb' and let us know how this goes...
___________

one MORE thing to inspect (but you already know this...)

CHECK THE RECEIVER for cracks/loose bolts and so on....

those OEM ge'em receivers aren't very good...

cheers
2air'

[Ag&Au]

Originally Posted by finalcutjoe

Ken,

My tire guy at Discount Tire told me same thing.. he actually tried to talk me out of the LTX AT2's because he said the 'aggressive tread' pattern would adversely affect towing performance...
Because I'm an expert in everything, I 'pishawed' him...

Tx,
Joe

It may make you feel better to know that I have towed with the tires since they settled down, and they do just fine.

When not towing, they have been a big improvement over the OEM tires in the snow and mud.

However, when they wear out, I will get something a little less agressive so I don't go through the break in again.

Ken

[boondockdad]

Ken,

No question... I replaced Firestone Transforce HT with these Michelins, and they are superior in snow, mud, and beach sand

Didn't notice any difference in ride... did notice more road noise...

-J