G body shuffle

[403Olds]

My 94 Roadmaster had the “Jeff bar” from the factory also

 

[64nailhead]

The frame tilting side to side in relation to the axle is what causes the shuffle. The rear a-arms have nothing to do with the shuffle. Frame twist in stock form, adds to it as well, but it's not the main cause.

If you tie the body to the left side of the rear axle, then the shuffle will be gone.

 

[565bbchevy]

So I am curious who is "Jeff" and what year did he come up with this rear bar?

 

[64nailhead]

So I am curious who is "Jeff" and what year did he come up with this rear bar?

I have a 'Jim' bar that I have $25 of materials tied up in, and about 4 hours of cutting, grinding, drilling and painting. Mine also doubles as a primary fuel filter mount. After I put on a trailer hitch on, the 'Jim' or 'Jeff' bar is really just added weight haha.

I will say that tying the rear of the frame rails together is a good idea. But considering the mounting points are the 8mm bumper mount bolts, we have to be realistic about the actual benefit of the 'Jim' Jeff' bar. If there was any true side load (sheer) put on those mounting bolts from a heavy frame twist, then I'm sure that the bumper shocks, and the bumper that is attached to to them, would be laying on the ground behind me.

A stock style trailer hitch has to be at least 5-10 times stronger than the Jeff bar because it supports the frame tails at the same bumper shock bolts AND a 1/2" bolt approximately 16" forward on the frame tails.

 

[69hurstolds]

So I am curious who is "Jeff" and what year did he come up with this rear bar?

IIRC, a long long time ago, in a galaxy far far away...wait...

Around the turn of the century, a dude named "Jeff" Davis or David or something like that used to make bars from common barstock to bolt across the frame ends. Using stiffening bars actually started before him, but I guess he more or less commercialized it more and would make them for people. AFAIK, he didn't do it for that long but it was hence known as a "Jeff" bar.

I'm in agreement that those tiny bolt points would suffer with lots of torsion forces applied. But any stiffening of the rails is welcomed. If you have a stock car, you'd definitely feel a benefit. But if'n I were doing it, I'd weld a bar across the ends of the frame. Or if I really wanted to do a "bolt on" deal, I'd configure it to use heavier duty bolts in the bottom of the frame rail somehow instead of the shock bumper bolts.

 

[565bbchevy]

I'm in agreement that those tiny bolt points would suffer with lots of torsion forces applied. But any stiffening of the rails is welcomed. If you have a stock car, you'd definitely feel a benefit. But if'n I were doing it, I'd weld a bar across the ends of the frame. Or if I really wanted to do a "bolt on" deal, I'd configure it to use heavier duty bolts in the bottom of the frame rail somehow instead of the shock bumper bolts.

Back in 2000 is when I bought my mig welder and made my roll bar and I also did my frame notch and welded in bars going across the frame for support and one is the rear and I know I was late to the game but it wasn't until 2010 that I bought a computer and had internet access for the first time and was able to see what others were doing out there, even seeing kits for a frame notch at some point not knowing it was a thing.
For my Regal I made a bolt on rear bar using the same roll bar tubing and welding it to 1/4" plate and opening up the mounting holes to use larger grade 8 bolts.

 

[melloelky]

https://www.gnsperformance.com/bodyframe-g-body?lightbox=i0u3l

if you kids are looking for a little bolt/weld in project check these brackets out.i paired a set up with some 4" rectangle stock.certainly won't hurt.

 

[scoti]

IIRC, a long long time ago, in a galaxy far far away...wait...

Around the turn of the century, a dude named "Jeff" Davis or David or something like that used to make bars from common barstock to bolt across the frame ends. Using stiffening bars actually started before him, but I guess he more or less commercialized it more and would make them for people. AFAIK, he didn't do it for that long but it was hence known as a "Jeff" bar.

I'm in agreement that those tiny bolt points would suffer with lots of torsion forces applied. But any stiffening of the rails is welcomed. If you have a stock car, you'd definitely feel a benefit. But if'n I were doing it, I'd weld a bar across the ends of the frame. Or if I really wanted to do a "bolt on" deal, I'd configure it to use heavier duty bolts in the bottom of the frame rail somehow instead of the shock bumper bolts.

x2. And whatever you use for the bar, it needs to be captured on two sides/plains of each rail.

 

[Rt Jam]

The bumper will tie the left and right frame together better than any square tubing connected by 1 bolt on each side. Also agree with some of this stuff is just adding weight. Just like the shock mount tower brace. How is that adding any strength to something straight across. Have you seen the section of frame behind the rear seat.
It would either need to be built like an I beam for a building or tied into a roll cage so it can reach up like a triangle. Triangles add strength. Things that a flat are not strong.

I would agree if the suspension was attached to the end of the frame but it's not. It's attached to a very beefy section in the kick up area.

I like the Blazer sway bar idea. I don't think the OEM bar will bolt up to my round lower control arms properly anyways.

 

[pagrunt]

I like the Blazer sway bar idea. I don't think the OEM bar will bolt up to my round lower control arms properly anyways.

Not to sway you from your choice of sway bars but my OE bar fits my round UMI arms just fine. I don't thing any of the quality round lowers should have an issue with an OE bar unless the don't offer the mount holes.