Rear Sway Bar Options

[stkcode]

Any commets on Hellwig's rear sway bar? I'm not particually excited about the 1 1/8" bar...seems awfully small for a 3/4 ton, even though they are suppose to be solid and not hollow bars as most factory bars are. Hellwig claims that larger diameter bars can cause "plowing” when cornering...but I sceptical without some other third party opinions. As I'm beefing up the engine, I can feel the rear getting a bit too happy on turns, if I get carless on the throttle.

I ran across a 79 1 ton pickup (non-dually), 14 bolt with a nice 1 7/16" sway bar. With the sleeves being 3 1/2" dia., same as the 3/4 ton....I started getting evil thoughts of swapping the rear (yes...I already see the several issues with doing such a swap). My 3/4 ton has 3.73 gears...which I can't complain about and I have no idea what the 1 ton rear is, likely 4.10 or lower. Which may be a bit lower than desired.

Which leaves me back to Hellwig's sway bar...opinions please....

[stkcode]

Ugh...that should have been 1 1/16" and not 1 7/16".

[Bob Gervais]

The Hellwig should be fine. You always want the bar on the drive axle to be the smaller one. The factory front bar is 1 1/2", so it seems like the Hellwig bar would be a good choice.

[fiream]

"Hellwig claims that larger diameter bars can cause "plowing” when cornering.."

I hope the above is in reference to the front bar. If it's not then you definitely need to look elsewhere for a bar as they don't have a clue what they are selling.
Increasing the front bar size/tension increases understeer (plowing). Adding or increasing rear bar size/tension decreases understeer. That's the reason most American vehicles either have no rear bar or a really wimpy one. An understeering vehicle is less likely to get the average driver in trouble. Decreasing understeer can make a vehicle feel better during normal driving but in a situation that requires evasive action, can quickly translate into oversteer which is a very dangerous thing for most drivers. Once the back end starts coming around most drivers are just along for the ride and have little or no control of the vehicle.
The front and rear bars need to be matched or tuned to work together or you will end up with an unsafe situation that may not manifest itself until you get in a bind. Installing a bar on a Suburban that didn't have one should bring it closer to a neutral handling vehicle but the closer you get to oversteer the easier it will be get it to break loose not harder.
If you get a bar and later feel it could be bigger, replace the rubber bushings on the rear bar with poly bushings as this will be the same as increasing bar size.
Since a Suburban is never going to handle like a Trans Am or a Vette, I would look in the salvage yards for a factory bar that you can get with all the hardware as you know this will give you a properly engineered setup. Be sure and check the front bar and if different than yours you might want to get it as well.
This is fairly involved subject whose surface can barely be scratched here. If you want a better understanding of some of the forces involved do a Google on polar moment of inertia. It particularly applies to heavy vehicles like Suburbans. Good Luck whichever way you go and be safe.
Fiream

[stkcode]

Thanks for the replies.

I went ahead an pulled the 14-bolt FF rear and got both the front and rear torsion bars off the 1-ton. I couldn't find my mic till I got home but it turns out the front torsion bar off a 1-ton non-dually is the same dia. as the 3/4 ton suburban (probably due to the GVW being so close between the two). So it looks like the rear torsion bar should work nicely with my existing front bar as soon as I replace the bushings. I'm gonna also rebuild and replace the rear 1-ton brakes and drop'em in my burb. They are a little bigger in overall height and width which would be more ideal for towing stopping power.

Strange thing is that both Hellwig's front and rear bars for the burbs are the same dia...odd.

[jimfulco]

The Hellwig bars may attach differently, and so may have a different-length lever arm working on the bar.

[500dana]

What is the largest factory rear sway bar? Thanks