The KidWagon

[KidWgn]

Still having an issue with a rear end "shake". I thought it was the OE wheels, as one was bent. That's what started all this modding.

The truck has now shaken the SECOND bolt loose from the trailing arm drop shackle; the vertical bolt that stops the shackle from moving up/down.

So, to remedy all of this, when I ordered my Spohn panhard bar, I went ahead and ordered their entire kit with adjustable upper and lower arms as well. Will be installing this weekend. Any advice from the pros on starting settings? From what I'm picturing, I think I should shorten both? My end goal is to get the axle centered into the wheel wells, and use the panhard bar to center left to right.

 

[KidWgn]

@89Suburban why the shocked face?!

 

[iamdub]

I wasn’t serious.

After watching the story of Doug's Suburban unfold, I couldn't put anything past anyone these days.

 

[iamdub]

Still having an issue with a rear end "shake". I thought it was the OE wheels, as one was bent. That's what started all this modding.

The truck has now shaken the SECOND bolt loose from the trailing arm drop shackle; the vertical bolt that stops the shackle from moving up/down.

Describe the shake. Changes with speed? Is more intense within a particular range of speed? At low speeds and light braking, does the brake pedal pulse?

So, to remedy all of this, when I ordered my Spohn panhard bar, I went ahead and ordered their entire kit with adjustable upper and lower arms as well. Will be installing this weekend. Any advice from the pros on starting settings? From what I'm picturing, I think I should shorten both? My end goal is to get the axle centered into the wheel wells, and use the panhard bar to center left to right.

You would lengthen them, not shorten. The difference is about 3/8"-1/2". Or, just measure the fender opening to the edge of the wheel lip, tire or hub center and determine how far back you wanna relocate it.

If you have a really good eyeball, you can set the new arms by just measuring them against the stock ones. If you wanna ensure repeatable accuracy, a cheap way is to use a stock control arm as a guide to drill two holes in a straight piece of 2x4. Get a drill bit that fits snugly through the bushing eye to center it as accurately as possible and hold the bit/drill perpendicular to drill straight. Drill through the board and tap the bolts through the board with a hammer. Mark the side of the board the bolts extend from (opposite the bolt head/entrance side). A line across the length will do. This will be the "top/surface". The bolts will be spaced the original distance of the control arms. Cut the board in the center. Place the short edge of the 2x4 against the short edge of another 2x4 or 4' level or something straight and rigid. Spread the cut halves apart so that you have a 3/8" to 1/2" gap between them. The point of the drawn line is in case you get one end of the cut 2x4 turned around, you'd have a reference to properly orient them. Clamp the halves in place on the straightedge. You now have a jig to adjust the new control arms to whatever amount you wanna lengthen them.


Adjust the uppers by the same amount and install. Then, adjust them as necessary to dial in the pinion angle as it has likely changed some with the drop parts.

 

[KidWgn]

Describe the shake. Changes with speed? Is more intense within a particular range of speed? At low speeds and light braking, does the brake pedal pulse?

It happens between 65-75 mph. The intensity is sporadic, but it FEELS like a wheel out of balance. It's a left to right shake, for sure, not a "bounce". Doesn't happen at all during low speeds or during braking.

You would lengthen them, not shorten. The difference is about 3/8"-1/2". Or, just measure the fender opening to the edge of the wheel lip, tire or hub center and determine how far back you wanna relocate it.

If you have a really good eyeball, you can set the new arms by just measuring them against the stock ones. If you wanna ensure repeatable accuracy, a cheap way is to use a stock control arm as a guide to drill two holes in a straight piece of 2x4. Get a drill bit that fits snugly through the bushing eye to center it as accurately as possible and hold the bit/drill perpendicular to drill straight. Drill through the board and tap the bolts through the board with a hammer. Mark the side of the board the bolts extend from (opposite the bolt head/entrance side). A line across the length will do. This will be the "top/surface". The bolts will be spaced the original distance of the control arms. Cut the board in the center. Place the short edge of the 2x4 against the short edge of another 2x4 or 4' level or something straight and rigid. Spread the cut halves apart so that you have a 3/8" to 1/2" gap between them. The point of the drawn line is in case you get one end of the cut 2x4 turned around, you'd have a reference to properly orient them. Clamp the halves in place on the straightedge. You now have a jig to adjust the new control arms to whatever amount you wanna lengthen them.


Adjust the uppers by the same amount and install. Then, adjust them as necessary to dial in the pinion angle as it has likely changed some with the drop parts.

Very great idea on making the jig for repeatability. I'm a machinist by trade, so I have all kinds of handy measuring tools; I'll probably just measure them with a 24" ruler down to the hundredth. I wish I had access to the machines at home, that I do at work. I work for Boeing, so it's pretty frowned upon to bring in "home projects" lol.

 

[89Suburban]

@89Suburban why the shocked face?!

I don’t want to see bolts rattling loose and putting you in danger homie that’s all.

 

[89Suburban]

Guy I work with worked for Boeing in Philly eddy stone

 

[KidWgn]

I don’t want to see bolts rattling loose and putting you in danger homie that’s all.

I appreciate that more than you know.

Guy I work with worked for Boeing in Philly eddy stone

I'm in St Louis, MO...bit of a drive. haha

 

[Doug118]

After watching the story of Doug's Suburban unfold, I couldn't put anything past anyone these days.

And here I am contemplating going even lower lol

 

[KidWgn]

And here I am contemplating going even lower lol