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Old 07-01-2007, 07:17 PM   #1
mvfd70
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Adjustable panhard bar question

How much can the rear end be lowered before an adjustable panhard bar is needed? Also while I'm here, how low can the rear go before the shocks need to be relocated? Thanks

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Old 07-01-2007, 08:00 PM   #2
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Re: Adjustable panhard bar question

i believe that say anything lower than 5" needs an adjustable panhard bar
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Old 07-01-2007, 08:12 PM   #3
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Re: Adjustable panhard bar question

I have a 5" rear drop and was OK with the stock bar. I did however put an ECE super track bar kit on because of exhaust clearance issues.
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Old 07-02-2007, 11:06 AM   #4
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Re: Adjustable panhard bar question

Thanks. Anyone else? Also, what about the shock relocation?
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Old 07-02-2007, 11:35 AM   #5
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Re: Adjustable panhard bar question

I can't say exactly what the threshhold is for switching to an adjustable bar and relocators. 4-5" is what I've read. But I will say that those specs apply only to drop SPRINGS when it comes to relocators. If you use 2.5-3" lowering blocks plus 2-3" drop springs you do not get into that territory. In other words the blocks don't count in the calculation for determining when to switch to relocators because they don't change the shock geometry.

The bar IS affected by blocks however (until you switch to the ECE super track bar, in which case you're adjustable anyway )

If you do use blocks be sure they don't put anything such as the U-Bolt nuts below the rim line. 2.5" is what most people use. The bigger the rim, the bigger the block can be.
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Old 07-02-2007, 11:47 AM   #6
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Re: Adjustable panhard bar question

About 2" on both...
More drop than that and the springs are getting offset and the shocks are losing effective angle.
You can get away with running lower w/o changing those items, but the rearend will be sitting off to one side and the shocks will be worse than original.
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Old 07-02-2007, 11:55 AM   #7
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Re: Adjustable panhard bar question

every inch you lower with a stock bar you're offsetting the rear to the passenger side plain and simple geometry at work theres no magic that 4"is ok and at 5" its a magic number
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Old 07-02-2007, 01:28 PM   #8
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Re: Adjustable panhard bar question

with Cdowns; I did a 5' spring drop in the rear and it pushed my rear end over a substantial amount. My shocks are also laying at ~40 degrees. The Super Track Bar resolved the rearend issue, though.
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Old 07-02-2007, 04:01 PM   #9
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Re: Adjustable panhard bar question

I might be wrong here but i fail to see why blocks wouldnt effect the bar? One end is on the frame and the other on the rear end, a 5" drop no matter how it is achieved will move the rear closer to the frame which will effect the bar. only diff is you have longer springs and shocks because the trailing arms dont move as much.
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Old 07-03-2007, 01:02 AM   #10
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Re: Adjustable panhard bar question

Quote:
Originally Posted by itsmike2k View Post
I might be wrong here but i fail to see why blocks wouldnt effect the bar? One end is on the frame and the other on the rear end, a 5" drop no matter how it is achieved will move the rear closer to the frame which will effect the bar. only diff is you have longer springs and shocks because the trailing arms dont move as much.
i'm having difficulties thinking it through in my head, but the reason blocks don't effect the adjustble panhard bar is because the mounting plate can go in on top of the blocks.

for the factory panhard, if you just put blocks in, you're lowering the T arm, which is where the coils mount. so in that case, i would think your rear would still shift to the P side of the truck. the distance from the top of the rear end to the frame isn't changing as much as if you were to use drop coils, but it's still getting adjusted.... that clear as mud?
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Old 07-03-2007, 02:18 AM   #11
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Re: Adjustable panhard bar question

Just curious if anyone knows the length of the super track bar? From eyelet to eyelet.


sorry for the hyjack

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Old 07-03-2007, 11:14 AM   #12
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Re: Adjustable panhard bar question

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Originally Posted by sick69 View Post
Just curious if anyone knows the length of the super track bar? From eyelet to eyelet.
It is adjustable. I can't find the lengths of it fully collapsed/fully expanded.
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Old 07-03-2007, 12:49 PM   #13
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Re: Adjustable panhard bar question

I have ECE 2.5/4.0 suspension drops on my '69, and DJM 2.0/ 4.0 on my '96. The '69 has coil springs in the rear. I have the adjustable track bar AND the shock relocators. This truck rides and drives like bein' downtown wherever I go. As for the '96, it has leaf springs, no shock relocators and rides like crap. I blamed in on the 20's. Replace them with the 15x8's that had been on it. No improvement. It had ToxicShocks on all four corners. Replaced the rears with MonroeMatics. Much better. I have asked DJM about shock relocation and they say it is only matters on bagged vehicles. I am ready to try them on the '96. It can't hurt.

But for dropping the rearend, you need to keep the rear axle ass'y centered under the chassis. Whether that means that you have to alter the original and reweld it to the correct length or install an adjustable, you should consider it necessary. ECE wouldn't have gone to the trouble to develope the part it they didn't consider it worthwhile to have and install. With leaf springs, it is a non-issue as there is no Panhard rod. But I'm still gonna get the shock relocators.
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Old 07-03-2007, 10:01 AM   #14
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Re: Adjustable panhard bar question

Quote:
Originally Posted by IvelDesigns View Post
i'm having difficulties thinking it through in my head, but the reason blocks don't effect the adjustble panhard bar is because the mounting plate can go in on top of the blocks.

for the factory panhard, if you just put blocks in, you're lowering the T arm, which is where the coils mount. so in that case, i would think your rear would still shift to the P side of the truck. the distance from the top of the rear end to the frame isn't changing as much as if you were to use drop coils, but it's still getting adjusted.... that clear as mud?
I still would think that the rear moves 5" closer to the frame no matter if its a 2" block and 3 " spring or 5" spring. And the mounting of the pan hard is on the frame and the diff. Now the shocks mount on the TA's and those wouldnt be effected by blocks right? Maybe i'm just picturing it worng ...
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Old 07-03-2007, 12:12 AM   #15
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Re: Adjustable panhard bar question

Thanks. Gives me more to think about.
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Old 07-03-2007, 05:53 AM   #16
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Re: Adjustable panhard bar question

I`ve never lowered an inch or two.I agree with Pickmup.If I was lowering a truck(and I wouldn`t bother with an inch or two)I would figure on an adjustable bar.Just because when I alter a vehicles design I will do what it takes to compensate and keep it as close to correct geometry as possible.On shock locators.I always made those and made them to give the same angle as original.The more it`s dropped,the relocation point changes.
The idea is to restore proper alignment to as close to original design as possible for the best possible handling.
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