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Some of you who drive a 4x4 with a solid front axle might have faced the death wobble from time to time. The below is a comprehensive check on how to analyse and find a remedy to the death wobble. This was posted on another forum which I have copied it here for the benefit of those who need to find a solution to it.

 

Death Wobble isn’t similar to a wobble from an unbalanced tire which is usually only felt at about 48-56 mph, DW is by far worse. When Death Wobble hits you will know… it’s a violent shake from the front end that feels like the Jeep is about to fall apart. Usually when it happens, the only thing you can do to stop DW, is to slow down. 

The first steps to eliminate Death Wobble should be a visual inspection of each component, checking the bushings, the tire balance and the alignment. DW is usually caused by a combination of several of the following causes, and is not caused by one single part or item that needs attention. These are some common things you must check anytime you lift your Jeep. Death Wobble is experienced mostly on lifted Jeeps, however it is not uncommon for someone without a lift to experience the dreaded DW. Listed below are a few things you can check. 

-Check your Tires
1. Out of balance tires can cause shaking in the front end, which can lead to Death Wobble. If you have had a pop out in the desert its definitely advisable to get the tires cleaned up completely. A tire/rim that has been balanced can still have internal defects that lead to DW.
2. Make sure all of your lug nuts are tight, (it happens to the best of us) 

-Make sure you have a good alignment
1. After you get an alignment done, have them print out the numbers for you. An XJ should have a 7* positive caster angle. A lifted XJ can’t always have that high of a number because the pinion would become out of alignment with the front drive shaft. Pinion angle takes precedence over caster.
2. Make you sure you go to a shop that will adjust the caster if necessary (either by shims in the frame side of the LCAs, or adjustable LCAs).

-Check your Track Bar, play in this can cause the axle to shake. 
1. Bushings - check to see that they are not worn. Looks for cracks, and excessive play)
2. Angles - this angle should be the same as your draglink. Use an angle finders you can get at sears to determine this, don’t just eye-ball it.
3. Bolts – Make sure all bolts are tightened down to spec (some lift components have a different torque spec then)

-Check the Axle, your mounts may be worn
1. Check the axle mount. Here is a good write up on a wallowed out bolt hole
Jeepin.com - Fixing a trackbar bracket
2. Check your Universal joints, a binding or lose U-Joint can cause DW
3. On the frame end if you still use the conventional Tie Rod End or (TRE) make sure that there is no play in this, as play can cause DW.
4. Look/Check for worn/torn boots on ball joints/tie-rod ends.

-Check your Frame
1. Small cracks in the frame can cause the steering box to feel loose; shaking from DW can only make this worse. 33’s and larger should have some form of Steering box brace, or frame brace in.
2. If you have upgraded your frame mount, make sure its cranked down nice and tight. (best to use an impact gun)
3. A busted Frame Mount can cause play in the front end causing DW (Keep a watchful eye on the welds as welds in sheer can break over time.

-The more adjustable parts the easier it is to tune in your lifted suspension.
1. Adjustable Track Bar
2. Adjustable Upper and Lower Control Arms (upper ones above 4” of lift). Not only are they adjustable, but they are stronger. 


-Things to remember:
1. After any lift, get your Jeep professionally aligned, this is a REQUIREMENT, not a suggestion.
2. A Steering Stabilizer (SS) is not a quick fix for DW.
3. Make sure that the lift you purchase comes with all the required parts for a safe driving vehicle. (as long as its going to be a DD)
4. PLEASE ALWAYS DRIVE WITH YOUR FRONT SWAY BAR CONNECTED!


Entire list of everything that can cause death wobble:

-Front tires out of balance. Clean the tires if there was a pop out in the desert
-Front alignment out of spec
-Loose track bar
-Worn track bar bushings
-Worn track bar end
-Needing an adjustable track bar
-Bad bushings/joints in control arms
-Worn/damaged steering stabilizer
-Worn/damaged shocks
-Worn/damaged tie rod end
-Bad U Joint
-Bad ball joint
-Loose frame mount
-Steering box looseness
-Need drop pitman arm
-Drive shaft(s) not balanced
-Bad front hub assembly


Torque specs:

Item .........................……......Torque Ft. lbs. .............. Nm

Lug nuts (1/2 X 20 w/ 60* cone) .... 85-115 .............. 115-150
All tie rod ends .....................…..... 55 ...................….. 74
Steering (both ends) ..............…..... 55 ................….... 74
Shock absorber upper nut .............. 16 ................….... 22
Shock absorber lower nuts ............. 17 ................….... 23
UCA frame end .....................…...... 66 ..............…..... 89
UCA axle end .........................….... 55 ................….... 74
LCA frame end ......................…..... 85 ...................... 115
LCA axle end .........................….... 85 ...................... 115
Track bar frame end ..............…..... 60 .................…... 81
Track bar axle end .................….... 40 ..................…... 54
Track bar bracket bolts ..........…..... 92 ...................... 125
Track bar bracket nut .............….... 74 ....................... 100
Track bar bracket support bolts ...... 31 ....................... 42
Hub bolts (3) ..13MM................…. 75 ....................... 102
Hub - axle bolt…36MM...........….. 175 ..................... 237

If you have a lifted vehicle, make sure that the alignment shop you choose knows the variant specifications for lifted vehicles, and that they do NOT set it to the "default/stock" settings. 


Factory Original Alignment specs (stock):

Angle ............. Preferred ........... Range ............. Max R/L difference

Caster ............ +7.0* ....……….... +5.25* to +8.5* ......... 1.25*
Camber ........... -0.25* ....………... -0.75* to +0.5 ........... 1.0*
Total Toe-in .... +0.25* .………...... 0* to +0.45* ............. .05*
Thrust angle....….* to ± 0.15*

Information provided by Jeeps Unlimited

Above information is taken from the below link 

http://www.jeepforum.com/forum/f11/small-lift-death-wobble-969090/#/topics/969090

Edited by skumar83
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Nice post, but his first explanation contradict his first point itself - unbalanced tires.

And, one of the most important point missed here for any DW is few kgs of sand inside the tire after a pop-out. Spend 20 dhs and get it cleaned and balanced before going through above points.

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7 hours ago, Gaurav said:

Nice post, but his first explanation contradict his first point itself - unbalanced tires.

And, one of the most important point missed here for any DW is few kgs of sand inside the tire after a pop-out. Spend 20 dhs and get it cleaned and balanced before going through above points.

After last pop out i was only able to drive my jeep 1km then i pulled over. Saleem came and we change the tire. It was shaking like crazy.

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DW is quite different than unbalanced tires. Unbalanced tyres especially having sand in it will cause a lot of vibration but in isolation it's not a death wobble. DW is like how a manual car vibrates when the engine is about to die at low rpm multiplied by about 10 times at a  much higher speed. Yes unbalanced tires in combination with other loose joints can lead to a death wobble.

 

I have edited the post to include the effect of sand in tyres.

Edited by skumar83
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A humble request, when cut and pasting articles its only gracious and ethical to credit the author and website the article is copied from via a link at the end of the post.

I'm sure you would expect the same is someone published your post somewhere else. 

Thanks.

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46 minutes ago, desertdude said:

A humble request, when cut and pasting articles its only gracious and ethical to credit the author and website the article is copied from via a link at the end of the post.

I'm sure you would expect the same is someone published your post somewhere else. 

Thanks.

Appreciate the point you have raised. Updated the OP.

Edited by skumar83

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