Trying to figure out which way to adjust these when I install them (1 Viewer)

[Apounder]

So I have been chasing a rattle/ vibration that's pretty intense since I moved to 5in tjm springs and a 1in front spacer. I thought It was my factory front drive shaft so I ordered s double Carden, installed, no fix. So I am now assuming it's the angle of my rear differential so I ordered these adjustable metal tech rear upper links. So the question is do I adjust these longer or shorter to accommodate for my 5inch test spring lift?

 

[BoxYourEars]

Quoted from Slee: "The rear upper control arms form part of the rear 4 link suspension. When the rear suspension is lifted, the axle will rotate backwards thus forcing the differential pinion to point upwards. The result is that the pinion angle of the rear differential and the flange on the transfer case are not parallel anymore. This can introduce vibrations in the drive shaft. By making the upper rear control arms adjustable, one can rotate the pinion angle down and correct the angles, thus eliminate vibrations."

In essence, they should be shorter than stock (as required based on lift height) to rotate your axle forward bringing the pinion angle back to parallel.

 

[neal0124]

You'll have to measure your transmission output flange angle and your pinion angle to determine the direction you need to adjust the links.

 

[jcardona1]

Shorter, to make the pinion flange of the transfer case and rear diff parallel

 

[jonheld]

So I have been chasing a rattle/ vibration that's pretty intense since I moved to 5in tjm springs and a 1in front spacer. I thought It was my factory front drive shaft so I ordered s double Carden, installed, no fix. So I am now assuming it's the angle of my rear differential so I ordered these adjustable metal tech rear upper links. So the question is do I adjust these longer or shorter to accommodate for my 5inch test spring lift?

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You know instead of assuming, why don't you simply remove 1 driveshaft at a time and try to isolate the vibration. Or I suppose you can just keep throwing money at it. Eventually you'll hit it.

 

[Apounder]

Needed longer front ds anyway

 

[bobbynelson0730]

sub'd. Went ahead and purchased both the adj uppers and lowers a little while back when they were on sale. For now I just have it set up for shortest it can go on the uppers then aligned the lower bolts up. Wanting to see the garage method of measuring flange angles. local driveline shops want a pretty penny to just check angles for some reason

 

[neal0124]

sub'd. Went ahead and purchased both the adj uppers and lowers a little while back when they were on sale. For now I just have it set up for shortest it can go on the uppers then aligned the lower bolts up. Wanting to see the garage method of measuring flange angles. local driveline shops want a pretty penny to just check angles for some reason

You can check on your own with the truck parked on the street. Get a basic angle finder from harbor freight for $5 and pull your drive shafts. Then hold the gauge flush on each flange.

 

[Tredwards]

I ordered these uppers and lowers. They should be here by this weekend. I have already pulled the reardriveshaft for some TLC. My plan is to set the lowers to the stock length, then check the driveline angles with the gauge below. Then put the uppers on and adjust till flanges are aligned. Making sure to measure bolt to bolt difference to make sure the both sides are the same. Do y'all recommended anti seize or locktite on the bolts? I am also assuming you grease joints till grease oozes out of couplings.

 

[Apounder]

Ok so I just found out the new metal tech uppers are about an inch shorter then my stock uppers fully extended?