1-3/8 dia. front sway bar upgrade ?

[gearheadE30]

I've put rear sway bars on both of my RCSB's. One of the best handling mods I've done. Don't understand why GM never made them available at least as an option on the 1/2t 2wheel drive trucks.
My '97 has one from a 1/2t Suburban.
The '98's is an aftermarket one of some kind. J/Y find. A larger bar than the Suburban one.
Both have had urethane bushings installed.

They probably didn't have them from the factory for two reasons. One is that, with limited weight over the rear axle, adding a rear bar would result in more load transfer to the compressed side of the suspension in a corner or flexed situation, unloading the inside wheel and making it even easier to spin. I know it's easy enough to light up a wheel, wet or dry, on my open-diff K1500, and my old c1500 was even worse. The other is that increasing roll stiffness at one end of a vehicle will, all else being equal and ideal, remove traction from that end. Understeer is safe, and a big front bar with no rear bar is a pretty surefire way to give you understeer.

It was pretty common to not have a rear bar on smaller trucks, at least up until recently. Modern stability and traction control systems combined with the race to the highest towing capacity have made rear bars much more common even on single cab trucks.

 

[Donald Mitchell]

The SS454 was supposed to have a larger one.

 

[Erik the Awful]

There's a bit to unpack in what gearheadE30 said, but basically you don't want the rear suspension too stiff. The guys who used to race first-gen RX-7s, back when IT7 was still a thing, usually removed the rear sway bar. The factory rear suspension and Watts linkage could bind, causing the roll stiffness to spike and promoting the chance of a spin. Removing the sway bar was a band-aid.

In the '80s-90s GM built in more understeer than most manufacturers. It was thought that it was safer for drivers because they wouldn't lose control, but plenty of drivers wrecked their cars anyways, plowing off the road into obstacles that could have been avoided if the vehicle had better balance.

Personally, I bought a Suburban sway bar for my truck and I plan on installing it in the next few weeks.

 

[someotherguy]

While a couple replies above include a lot more informed knowledge than I've got on the subject, adding a rear bar on a couple of my lowered 400's was a huge improvement. I drove them like a madman and they handled beautifully. My 92 ECLB had an AddCo bar in the back, it was OK; I should have cut the end links in half so they had a better angle (they were meant for a stock height truck) - my 94 ECSB I installed the Hellwig bar that had a no-drill install and I liked that setup better, although the u-bolts that went around the axle tubes did better with a tack weld to keep them from self-adjusting.

You definitely can make a suspension too stiff, in a nutshell, in the corners it will lift the tire on the opposite side and you'll lose traction. And if you lose traction in that corner, you're gonna have a bad time.

Richard

 

[TheAutumnWind]

Bar torsion is diameter raised to the fourth power multiplied by some other things that I don't remember. so the 1.375" bar is ~50% stiffer than 1.25". 1.5" would be roughly double the stiffness, but I'm seeing the ridetech bar as a 1.438" which would be ~1.75 stiffer than stock.

I have the belltech 1.375" and an F-body 1" rear bar, it has really cut down on roll.

Is the fbody install any different than a truck rear bar?

 

[roostmeyer]

I'll try to grab a photo, I used it since I had a spare 3/4" and 1" bar sitting around already from my trans am. I went to the 1" when I put in the bigger front bar.

Basically I just drilled a ~5/8" hole in the bottom of the frame rail and made an end link with 3/8" all thread and a ~8" long piece of tubing. The end link bushings clamp up through the frame rail. I haven't looked at an SUV bar too close, but I'm guessing the f-body bar arms are a bit shorter, making it stiffer.

Just a PSA regardless of what you do with the sway bar, with polyurethane bushings YOU MUST CHECK FOR BIND. You typically need to toss at least 1 washer under one of the saddle clamp bolt holes or the sway bar will be locked down. I'd rather have it be slightly loose than stuck.

 

[sewlow]

I'll try to grab a photo, I used it since I had a spare 3/4" and 1" bar sitting around already from my trans am. I went to the 1" when I put in the bigger front bar.

Basically I just drilled a ~5/8" hole in the bottom of the frame rail and made an end link with 3/8" all thread and a ~8" long piece of tubing. The end link bushings clamp up through the frame rail. I haven't looked at an SUV bar too close, but I'm guessing the f-body bar arms are a bit shorter, making it stiffer.

Just a PSA regardless of what you do with the sway bar, with polyurethane bushings YOU MUST CHECK FOR BIND. You typically need to toss at least 1 washer under one of the saddle clamp bolt holes or the sway bar will be locked down. I'd rather have it be slightly loose than stuck.

...and urethane bushings require synthetic grease. No Dino-grease.

 

[Aarong23]

...and urethane bushings require synthetic grease. No Dino-grease.

Im curious. What would happen if you used regular grease on a poly bushing? I have always used the synthetic grease as required, but never questioned why.

 

[sewlow]

Kinda curious too. Never tried it though. Figure the manufacturer would know best.

 

[Aarong23]

Kinda curious too. Never tried it though. Figure the manufacturer would know best.

I just looked it up. Apparently, petro grease on poly bushings is much more prone to breaking down and drying up fast, causing premature bushing wear.