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View Full Version : Hellwig anti-sway bar install and test


sajohnson
03-30-2017, 03:56 AM
The installation was straight-forward, there were only a couple small issues:

1) Hellwig includes two (2) flat washers to be placed inside each end link, between the end link and the end of the bar -- just to take up the extra space. Actually, there is probably enough room for a second flat washer on each side.

2) The torque spec for all hardware is 75 ft-lbs. 75 ft-lbs on the end link bolts squeezes the end link (tabs? ears?) so that they are in firm contact with the washer on one side and the end of the bar on the other. The bar is pinched in the end link.

That may not matter, but the stock installation uses locking nuts so the end link bolts do not have to be cranked down tight. There is space between the end link ears/tabs and the end of the stock bar, so it is free to move.

3) From what I've read, Hellwig has solved the problem it had a while back with the bar mounting brackets breaking, but they look pretty fragile compared to the OE solid cast iron brackets.

4) There was some slight interference between the bar and the existing Firestone air bag mounting hardware. Needless to say, that's not Hellwig's fault, although I do recall reading a statement saying that the bar is compatible with all common aftermarket suspension mods.

The 'rocking test':

As we did previously to test the effect of more pressure in the air bags (result: more psi = less rocking, same number of oscillations) we backed the View up next to a picnic table so I could push on the very top of the wall, up under the drip edge. DW got up on a step ladder with a yardstick and held it fixed to the ladder, just above the high mounted vertical stop light strip.

* With the OE/stock setup and about 55 psi in the air bags we got 2" movement each direction (4" 'peak-to-peak') and 5-6 complete oscillation cycles. #6 was barely perceptible.

* With the Hellwig bar and same 55 psi in the air bags, we saw 1.5" movement (3" peak-to-peak) and 4 oscillation cycles.

Shocks are Bilsteins.

As with the air bag test, I was pushing as hard as I could, and kept rocking the rig back and forth until additional pushes would produce no additional motion.

BTW -- along with the lube for he bar bushings, Hellwig includes some blue thread locker.

sajohnson
03-31-2017, 05:42 AM
A couple hundred mile day trip confirms that the push from truck wakes is all but eliminated.

We did not encounter any significant crosswinds, so that judgment will have to wait.

I was not surprised that our testing of the bar (previous post) showed less side-to-side motion, but I wasn't expecting one full cycle less oscillation.

When we tested the air bags with different pressures, the amount of motion decreased with higher psi, but the # of oscillations stayed the same.

sajohnson
04-17-2017, 04:26 AM
Just a quick update -- during another short trip we did get a couple strong pushes from truck wakes.

That surprised me because with the Hellwig installed we barely feel most passing trucks.

I'm not sure what might explain the difference -- different tractors; different wind conditions?

Otherwise, everything is the same as I reported above.

There is less rocking when entering the coach as well as when driving over diagonal speed bumps, etc.

Needless to say, there's less sway in corners, but IMO the stock bar was adequate in that regard.