Wheel hop after traction bar install

Six_Sloww · Jun 7, 2015

My truck has never had a real issue with wheel hop, except on crappy roads. Since there are very few nice roads where I live I decided I wanted some traction bars as a layer of security and to lessen the chance of breakage.

I put the traction bars on about a month ago and they feel great. Lost a little traction due to zero axle wrap, but made up for it in how much more solid it felt under hard acceleration. We've had some cool weather here in late spring and the truck was feeling really strong, from a roll it would just burn the tires as soon as the truck hit lockup but it was still moving out really good as the tires do a good job fighting for traction in 2wd.

Fast forward to this first week of June, it's warmed up a lot and the few times I've hammered down hard when the truck starts to spin it actually hops really bad from side to side. Now that the axle isn't wrapping and the tires have a lot of traction on the sticky pavement it's just bouncing the ass of the truck from side to side.

First couple of times I figured it was just shi**y pavement. But the last few times I purposely waited for nice stretches of road and the stickier the surface the worse the hop.

Yesterday I was trying to take a buddy for a ride to show off the winter modifications. I roll into the throttle in second and like usual when it hits 3rd the tires start coming unglued, it starts hopping but this time instead of letting out I said *** it and stayed in it hard. Well obviously that was a bad idea, it gets so bad when I let off I actually got death wobble BAD. Wtf?!

I took the truck home put it up in the air and shook everything down real good.. Can't find any reasonable explanation for what happened. My only thought is because my truck is lowered so much the traction bar mounts are only 6" or so from the radius arm brackets.. I was thinking maybe there was so much energy being transferred from the wheel hop it actually unsettled the front end bad enough to make it death wobble?

Really have no idea where to go from here.. This truck is really kicking my ass, nothing I add on to it is going right at this point. I've only been making my truck worse.

Sorry for the long read.. Anyone have any idea what might be going on?

drunk on diesel · Jun 7, 2015

is your pinion angle correct?

Six_Sloww · Jun 7, 2015

Yeah it was shimmed with the shackle flip.

The side to side shimmy it's doing now started when the bars went on. I might pull them off and see what happens

Layson · Jun 8, 2015

Pictures of the bars?

Six_Sloww · Jun 8, 2015

little luke · Jun 8, 2015

What springs do you have on the ass end?

Six_Sloww · Jun 8, 2015

250 springs no overload, no block, djm shackle flip kit and a 2.5* (I think) pinion shim

Six_Sloww · Jun 8, 2015

boggerr · Jun 8, 2015

You have a old school wheel standing trick going on there. Back in the day they used to run bars that far forward to get the front wheels off the ground. Double check your front end, your probably picking the nose up and something isn't happy up there.
You may have to shorten the bars if it's possible.

Six_Sloww · Jun 8, 2015

That's kind of what I was thinking, I'm sure these bars work really well in trucks that are lifted way up, but with as low as my truck sits I feel like the bars might be too long for my application

Six_Sloww · Jun 8, 2015

Still doesn't explain why I went from no hopping issue to almost hopping every time I lose traction.

boggerr · Jun 8, 2015

Just thought of this. Before you pull the bars off, try to rig up some kind of limiting straps for the front end and take it for a spin

boggerr · Jun 8, 2015

With the bars being that long it transfers a lot of weight to the rear. It could be with the weight transfer and those tires get so damn sticky when hot

Six_Sloww · Jun 8, 2015

My other thought is.. And I could be wrong here, the factory LSD is really taking a crap in my truck, when it locks up good I can feel the ass slide a little and it won't hop. When it hops I stay straight as an arrow but who cares because the truck is bouncing like hell. I wonder if the difference in wheel speed is partly to blame

I wonder if a locker that would ensure an even wheel speed would help. Problem is I really need to stop spending money to "maybe" fix problems.

Six_Sloww · Jun 8, 2015

boggerr said:
Just thought of this. Before you pull the bars off, try to rig up some kind of limiting straps for the front end and take it for a spin

Limiting straps need to happen because my front axle hops on hard 4x4 launches

https://vimeo.com/130088468

Gearhead2012 · Jun 11, 2015

When you climbed under the truck and checked everything, did you check the front trac bar? (locates the front axle side to side...not to be confused with your traction bars) Generally, anything death wobble related, the trac bar is my first suspect.

If it's the rear of the truck that feels like it's weaving side to side, then your factory limited slip could be partially to blame...though normally I've seen trucks just push past the clutches in the diff and do the one wheel peel, but I have seen a few try to grab from side to side as the clutches heat up. FWIW, a locker was maybe my favorite thing I've done to my truck. Check your front hubs too...I've had mine stick and cause wired things in the steering, even in 2wd.

Also, do you have any pics of the shackle flip?

Six_Sloww · Jun 12, 2015

That's the kit, I kept the stock shackles, flipped the hanger (2nd notch) and shimmed the pinion.

Locker might be next just because I want one anyway.

Only tough part will be deciding to stay with 4.30 gears or not.

Gearhead2012 · Jun 12, 2015

Out of curiosity why the shackle flip?

I've got 355/65/18's (36-37" tall) tires, and I am happy with the 4.30ratio...my guess would be with those smaller tires you're over 2k RPM at highway cruising speed? It'd be way over geared compared to stock that way with 4:30's...but I bet it's fun to drive though, especially with a locker.

Does the steering feel weird or death wobble on a hard pull on the highway, say 60 mph plus, where traction should be less of an issue? And, on the flip side, does the steering get all wishy-washy if you launch it on a wet road where there's no real traction? Just curious if the traction bars loading the frame are an issue, or if something is working loose.

Six_Sloww · Jun 12, 2015

Gearhead2012 said:
Out of curiosity why the shackle flip?

I've got 355/65/18's (36-37" tall) tires, and I am happy with the 4.30ratio...my guess would be with those smaller tires you're over 2k RPM at highway cruising speed? It'd be way over geared compared to stock that way with 4:30's...but I bet it's fun to drive though, especially with a locker.

Does the steering feel weird or death wobble on a hard pull on the highway, say 60 mph plus, where traction should be less of an issue? And, on the flip side, does the steering get all wishy-washy if you launch it on a wet road where there's no real traction? Just curious if the traction bars loading the frame are an issue, or if something is working loose.

It's the only way to get the truck lower than just removing the blocks my truck is one of the lowest 4x4 trucks around

My cruising speed is way up there usually about 2500 rpm at highway speeds but the truck seems to love it believe it or not, keeps my biggish non vgt charger in boost and I can get about 17 mpg.

The truck really handles well between the wide street tires and sitting nice and low. I haven't ever had any issues with death wobble before. It's strictly when I lose traction enough for it to do the side to side bounce and even then the wobble has only happened once. Probably because it got to hopping so hard it unsettled the front end