Devilfrog
NAXJA Forum User
- Location
- Duncan, BC
OK so the background info ...
2000 XJ, ~5.5" lift, WJ swapped knuckles and 1 ton steering.
Prior to the WJ swap I had no death wobble, zero.
when we did the swap we swapped in a set of RE1310 4.5" coils (164lb/in) and 1" spacers. Previously I had some RE TJ 4.5" coils (219lb/in) and 1 3/4" spacers. Old used Rancho front shocks. We also did New WJ ball joints and new wheel bearings at the same time
My death wobble has me and other stumped ... as it requires a specific series of bumps, or a specific sized bump above a specific speed. Currently that speed is 85kph (~55mph).
I can drive all day long at 120kph if I don't hit that specific kind of roughspot, but when I do ... it's an axle bouncing hell ride until I slow down to around 30kph (not sure I'm too busy soiling me undies). With the WJ brakes I can hear that the tires are coming off the ground as I chirp as the tough down locked up while in the air. The steering wheel actually doesn't move a whole lot, there is a shimmy to the wheel but that's about it through the whole ordeal.
It starts with "That Bump(s)" and then there is a quick shimmy of sorts (about 7 bounces), and then it just progresses and feels as if the axle is tearing itself apart.
This is Death Wobble, not just a general shimmy, shake or Vibration I can speed up up or slow down through. Once it starts, that's it, I'm along for the ride until I can stop enough. If it hits at 85kph, it's the same as 110kph ... it just takes longer to stop (thankfully the WJ brakes front and ZJ rears make that a short stop).
My thoughts now are the soft springs are causing the shocks to "fade out" of sorts, as there is no excessive side to side action on the steering wheel, making this more like axel bunnyhop. and it seesm the shimmy I do feel is more the result of the trac bar push/pulling the axle while on it torrent.
I'm going to try BDS 4.5" coils in hopes that my springs are just simply too soft for my shocks. I did replace the front shocks for a set of Pro-Comps for a 4" lifted JK as that's the compression and extension lengths I needed and the valving should be similar given the ranges of vehicles it covers (durango, dakota, JK). Caster is at 5degrees and toe is at 1/16" in. Tracbar is a custom jobby torqued to ~110ft-lbs (uses Rusty's bushings and was made using the old Rusty's bar I had on the XJ before). Bushings are all good and everything is tight. Checked by me and a few mechanics (trusted 4x4 shops not just old Joe down the road).
Any suggestions, is my thinking sound?
2000 XJ, ~5.5" lift, WJ swapped knuckles and 1 ton steering.
Prior to the WJ swap I had no death wobble, zero.
when we did the swap we swapped in a set of RE1310 4.5" coils (164lb/in) and 1" spacers. Previously I had some RE TJ 4.5" coils (219lb/in) and 1 3/4" spacers. Old used Rancho front shocks. We also did New WJ ball joints and new wheel bearings at the same time
My death wobble has me and other stumped ... as it requires a specific series of bumps, or a specific sized bump above a specific speed. Currently that speed is 85kph (~55mph).
I can drive all day long at 120kph if I don't hit that specific kind of roughspot, but when I do ... it's an axle bouncing hell ride until I slow down to around 30kph (not sure I'm too busy soiling me undies). With the WJ brakes I can hear that the tires are coming off the ground as I chirp as the tough down locked up while in the air. The steering wheel actually doesn't move a whole lot, there is a shimmy to the wheel but that's about it through the whole ordeal.
It starts with "That Bump(s)" and then there is a quick shimmy of sorts (about 7 bounces), and then it just progresses and feels as if the axle is tearing itself apart.
This is Death Wobble, not just a general shimmy, shake or Vibration I can speed up up or slow down through. Once it starts, that's it, I'm along for the ride until I can stop enough. If it hits at 85kph, it's the same as 110kph ... it just takes longer to stop (thankfully the WJ brakes front and ZJ rears make that a short stop).
My thoughts now are the soft springs are causing the shocks to "fade out" of sorts, as there is no excessive side to side action on the steering wheel, making this more like axel bunnyhop. and it seesm the shimmy I do feel is more the result of the trac bar push/pulling the axle while on it torrent.
I'm going to try BDS 4.5" coils in hopes that my springs are just simply too soft for my shocks. I did replace the front shocks for a set of Pro-Comps for a 4" lifted JK as that's the compression and extension lengths I needed and the valving should be similar given the ranges of vehicles it covers (durango, dakota, JK). Caster is at 5degrees and toe is at 1/16" in. Tracbar is a custom jobby torqued to ~110ft-lbs (uses Rusty's bushings and was made using the old Rusty's bar I had on the XJ before). Bushings are all good and everything is tight. Checked by me and a few mechanics (trusted 4x4 shops not just old Joe down the road).
Any suggestions, is my thinking sound?