OP
The frequency is too fine to see. I've even tried audible sensors placed on both diffs and the TC with headphones and can't pinpoint it.
Re-geared, now I have a vibration above 50 mph
- Thread starter bobthetj03
- Start date
The frequency is too fine to see. I've even tried audible sensors placed on both diffs and the TC with headphones and can't pinpoint it.
White Shadow 99
Member
Have not posted recently. I have vibs on a 06 LJ after 5.13 regear. Isolated it to the front drive shaft. If I remove F. DS, it goes away. F. DS is new and has been rebalanced. Played with pinion angle many times under and over zero delta. It does make a difference but does not solve problem.
TT will only increase DS angle F & R. I assume What the ‘expert’ was referring to was raising just the rear of the TC or changing the angle, not raising the entire unit. Remember the engine, tranny and TC are all bolted together everything moves/raises/lowers together. I have a TT, 1.25” BL and 1” MML. I have UCF aluminum skid, that may rule out skid harmonic theory for some of you. My next move is to remove MML, it reduces rear DS angle but increases front DS angle by changing angle of entire drivetrain including TC yokes. I would be interested in driving each other’s rigs and comparing. I am in Sacramento, CA
I WOULD ALSO LIKE TO TALK TO THAT TRAVELING EXPERT MENTIONED EARLIER, anybody know how to get a hold of him ??? If he can solve my problem i would gladly pay him.
I am not quite ready to throw down $1600-2000 for hub conversion.
TT will only increase DS angle F & R. I assume What the ‘expert’ was referring to was raising just the rear of the TC or changing the angle, not raising the entire unit. Remember the engine, tranny and TC are all bolted together everything moves/raises/lowers together. I have a TT, 1.25” BL and 1” MML. I have UCF aluminum skid, that may rule out skid harmonic theory for some of you. My next move is to remove MML, it reduces rear DS angle but increases front DS angle by changing angle of entire drivetrain including TC yokes. I would be interested in driving each other’s rigs and comparing. I am in Sacramento, CA
I WOULD ALSO LIKE TO TALK TO THAT TRAVELING EXPERT MENTIONED EARLIER, anybody know how to get a hold of him ??? If he can solve my problem i would gladly pay him.
I am not quite ready to throw down $1600-2000 for hub conversion.
White Shadow 99
Member
By the way, no vibs at 80 in my 99 Auto TJ with 3.73 gears, 4” lift, 33” tires, SYE and 1” lowered stock skid. Never took out the skid spacers to see what happens, kinda scared actually. Ain’t broke, don’t fix it.
FYI 06 LJ is also auto
FYI 06 LJ is also auto
Two things- you aren't off in your thinking at all. We see it all the time. One of the rigs we care for will complain about DW, temps will drop making it cooler and DW goes away. When they warm back up, DW comes back with no other change. So temp does affect the stiffness of the structure and how it reacts to a harmonic vibration.
Second thing, I was discussing this with someone much smarter than me last night and he proposed that a lot of the vibe complaints we hear about right after a gear swap could be due to the gears themselves and how they are lapped in at the gear factory. How to go about testing and proving that is a real pain in the butt but I don't have anything I could use to shoot his theory down.
Great I just ordered the MML, and BL getting ready for the TT. I’m in Redding so if you are around or 1/2 way let me know I’d be interested as well. Thanks for the info
OP
My vibe seems to be centralized to the rear DS. I pull the rear DS and the vibes are virtually gone. Pull the front DS, vibes are slightly better, but still there.
OP
My next step will be to take my jeep to a offroad shop in Sacramento and have them take a crack at it. Will have them check the rear gear setup, but like you said, may be hard to pinpoint if it hiding in the gears themselves.
I couldn't see how a simple visual check would prove or disprove anything. Of course you can check the pattern and backlash. A good to check would be carrier run out as well. The only other thing would be a new gear set.
White Shadow 99
Member
For reference, my brand of gears are Revolution. Based on my research, they had the best tolerances and manufacturer is higher quality then average.
White Shadow 99
Member
when you put in new gears, an then you put the driveshaft back on, on the first turning, is it possible that the gears where not aligned properly, an like that first turn, could have bent the shaft? never seen gears put in an rebolting of shaft. are you supposed to turn the gears without the shaft hooked up? in initial phase?
has anybody put the gears in, but they were locked up, an bent the drive shaft from that, cause they didnt turn the gears to make sure they were meshing together but they then in turn become unlocked an turned fine afterwards, after the first lock up cleared out, but then a vibration, but was from the bent shaft that occured, in the initial turning of the driveshaft, cause the gears were initially locked up.hold on i will draw a picture....
that line up the dudes neck in pic 3 is the collar from a high end collar shirt.
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You can't set up gears in a TJ axle without turning the pinion to check the pattern so the answer is no, they weren't locked up enough to bend the driveshaft and if they were in fact locked up, it typically twists the pinion off or breaks the CV joint. If you do it at speed, it breaks the axles.View attachment 37512
hold on i will draw a picture....
At some point, one would think he would run out of crayons.
Lol. Nope. I've been lurking here and learning long enough that I figured I'd finally make an account. Seems that there's only a little carry over of members between the forums so I started a new build thread here too.
Do you want a stalker? I can check if weldedcambolt is interested in the position.
