slight clunk and a Grrrrr

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RFB

97 FZJ80 LIFTED SC DUAL BATTERIES,37s
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Ok I have been doing a laundry list, axles,bumpstops, delta panhard bearings/races skid plat new rack new RTT new battery setup and new rear drawer. SO yea that has resulted in a lot of questions So I apologize BUT let me ask with the truck entirely empty no rack no RTT no nothing single battery no winch shes super light and the tailgate dropped and measured from ground is at 39in off ground. would the height gained from being empty cause the drivelines to have a grrrr? she will be loaded down again soon but Im curious about the new Grrrrr remember I have fairly new OEM front DC DS(tacoma DC cut down) and a new OEM rear DS when starting from a stop theres a slight clunk( I know that not much) But its usually tight and its driving me crazy. does any of this make sense at all?
 
With a new and well maintained shaft I wouldn't think so, but I had the exact same problem happen with mine after adding a bumper with swingouts. That 1" lower ride height made the old joints grrrrrrr at highway speed.
 
With a new and well maintained shaft I wouldn't think so, but I had the exact same problem happen with mine after adding a bumper with swingouts. That 1" lower ride height made the old joints grrrrrrr at highway speed.
yea I wondering with the 7in spring stretched all the way UP its causing a driveline Grrrr im pulling front then rear to see if its isolatable(made up word)
 
With no extra weight on the rear the springs will relax and your rear ride height will increase. Your pinion angle will change (rise) when this happens, it even changes under hard acceleration. Its best to get your weight in the rig and then dial in the pinion angle so you reduce/ eliminate the Grrrr.
At rest, with vehicle fully loaded with permanent weight (roof rack, Alu-cab, rear drawers, fridge...) your pinion angle should be about 1-1.5 degree's lower than the output drive line flange angle of your transfer case to account for pinion rise under acceleration.

Clear as mud?
 
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I found that with stock OEM (new) bushings in my upper control arms that they squished to much under acceleration with my Super Charger adding so much extra torque. I ended up going with Poly bushings in my upper control arms and OEM bushings in my Lower control arms to control pinion rise.
 
With no extra weight on the rear the springs will relax and your rear ride height will increase. Your pinion angle will change (rise) when this happens, it even changes under hard acceleration. Its best to get your weight in the rig and then dial in the pinion angle so you reduce/ eliminate the Grrrr.
At rest, with vehicle fully loaded with permanent weight (roof rack, Alu-cab, rear drawers, fridge...) your pinion angle should be about 1-1.5 degree's lower than the output drive line flange angle of your transfer case to account for pinion rise under acceleration.

Clear as mud?
thats what I thought just wanted to run in by the class first, beofre another thing ends up on my list. Im almost ready to roll out I hope. lol thanks Zilla
 
ok the slight Grrrrrr is gone now that truck is loaded again for th road, took out bth DS AGAIn and greased them and remember these are brand new OEM driveshafts with 12K on them and Im still getting a clunk at take off, any clues??
 
Unloaded weight will change your pinion angles. A magnetic angle finder is your friend here...use it to dial in you pinion angle...you want 0 degrees difference between pinion flange and exfer case flange.
Clunk could be a bunch of things...how is it on deceleration?
 
well Im not concerned about the pinion angles its a non issue, truck was totally unloaded (which its never been) caused a grrrr which is now gone. there isnt anything on deceleration or I would have mentioned it. 2 almost new OEM DS one is clunking ever so slightly and they are freshly greased.
 
Sounds like you have it all sorted then.
It appears so laying in the rain in driveway trying to get rolling, just wanted to nail this down first. smoked the front tires tho lolol
 
Driving around with so much spring height and an unloaded rig will have had your pinion angles too far apart from each other...causing the vibes you were feeling.
Driving like that will also quickly destroy your u-joints...its all related.

A magnetic angle finder is a very cheap tool to buy and if used correctly can save you a ton of money in replacing parts that have worn out due to bad geometry.
 
I would only use an OEM joint, especially with the angles/lift you have!!!
 

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