Prorock 44 pinion angle?
#1
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Prorock 44 pinion angle?
Hey everyone. I have a nasty hum from my front end from 40mph on. I threw my angle tool on my pinion and on top of a C...and on top of the greasable/adjustable ball joints. Im no expert, but it looks like these measurements are off? Mods: adjustable long arms, adams driveshaft, prorock 44. 35.7" measured tire. Total lift of about 3.5". All parts installed by and aligned by a reputable shop. Does this look right or am i measuring wrong? I know what the dynatech website says for the angles, but i dont know if other mods come in to play.
#2
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Is it a brand new pr44 install, or it's been there a while and just the vibes are new?
Is it the regular or the unlimited housing?
Post the alignment printout that the reputable shop gave you. I'd kind of like to see that before we start jumping on just how far off those angle finder numbers are.
Is it the regular or the unlimited housing?
Post the alignment printout that the reputable shop gave you. I'd kind of like to see that before we start jumping on just how far off those angle finder numbers are.
#3
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I wasnt aware there was an unlimited vs regular housing. Whats the difference? Working on getting the prntout for alignment. The loud hum (no vibration) actually started when i had the adams driveshaft installed. That was when i was on a d30. Wheels, tires, bearings, and front axle were all changed....still get the hum.
Note, looks like driveway has a 3 degree slope
Note, looks like driveway has a 3 degree slope
Last edited by allcarfan; 05-05-2019 at 01:00 PM. Reason: Add driveway angle
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https://www.dynatrac.com/downloads/P...20FAQ_revK.pdf
The regular pr44 (and stock front housings) have 6 degrees separation between caster and pinion. (4* caster = 2* at the pinion) The unlimited housing is designed for lifted rigs and has 10 degrees separation (8* caster = 2* at the pinion)
Which way is the ground sloped? (is that pic 7* at the pinion, or 13*)
The regular pr44 (and stock front housings) have 6 degrees separation between caster and pinion. (4* caster = 2* at the pinion) The unlimited housing is designed for lifted rigs and has 10 degrees separation (8* caster = 2* at the pinion)
Which way is the ground sloped? (is that pic 7* at the pinion, or 13*)
Last edited by nthinuf; 05-05-2019 at 01:39 PM.
#5
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Im going to assume it is a pr44 unlimited as it has 1/2" thick axle tubes and rebuildable ball joints from dynatrac....unless there is an alternate way to identify.
Front of jeep would be 3 degrees higher with slope of driveway.
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So if this were level ground, the right side of the pic would be be lower, which would shift the needle 3* to the left, correct? So, 7* at the pinion.
If my admittedly weak math skills are working, with a corrected housing (10* separation), 7* pinion would be 3* Caster. (though your other pics are showing, what, about 17* caster? Or 14* after removing the slope?)
Either way you look at it, as 3* Caster through separation math, or as 14* Caster on the angle finder, it's not really close to the 6-8* range suggested by Dynatrac. Which brings us back to the alignment printout...
I seem to have misplaced my angle finder, but if I come across it I'll snap some pics at both of those spots on my PR44 and see how they compare.
If my admittedly weak math skills are working, with a corrected housing (10* separation), 7* pinion would be 3* Caster. (though your other pics are showing, what, about 17* caster? Or 14* after removing the slope?)
Either way you look at it, as 3* Caster through separation math, or as 14* Caster on the angle finder, it's not really close to the 6-8* range suggested by Dynatrac. Which brings us back to the alignment printout...
I seem to have misplaced my angle finder, but if I come across it I'll snap some pics at both of those spots on my PR44 and see how they compare.
Last edited by nthinuf; 05-05-2019 at 03:24 PM.
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#8
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Sorry, I just re-read your earlier post. I was thinking driveline vibes due to bad caster. But you said No Vibrations, and there is a 'hum' that started with the installation of the double cardan driveshaft.
So, some other possibilities for the the hum might be a driveshaft that isn't balanced properly (threw a weight, damaged in shipping, not balanced properly before it was shipped, whatever. I want to think that this would cause vibes though), or maybe a problem with the flange/yoke swap when going to the new driveshaft (which might be negated if the pr44 came with the gears/flange already installed?)
So, some other possibilities for the the hum might be a driveshaft that isn't balanced properly (threw a weight, damaged in shipping, not balanced properly before it was shipped, whatever. I want to think that this would cause vibes though), or maybe a problem with the flange/yoke swap when going to the new driveshaft (which might be negated if the pr44 came with the gears/flange already installed?)
Last edited by nthinuf; 05-05-2019 at 04:58 PM.