OK, I've got a weird death wobble issue.

'01 F250 CCSB 4x4. V10. 4.30 posi gears. 1 ton overload springs.
Has a 2 1/2" level lift spring kit in front.
Welded a 1/2" plate to the stock block to level the rear.
Put on new Power stop Tow package drilled and slotted rotors and pads.
New Bilstien 5100 shocks all around.
Replaced the rear axle outer hub bearings.
Replaced the front hub bearing assemblies.

Have several thousand miles on this setup.

Deathwobble started recently.

Had a leak in the driver side rear hub inner seal. Finally got a good seal that works. Also cleaned the oil out of the rotor and tried to clean the pads and rest of the assembly.

I can drive the truck and all is fine. As the truck begins to warm from driving sometimes, I start to get the front end death wobble. When this starts, I notice that the truck tries to pull left. I have to steer right to make it go straight.
When I hit the brakes to stop, the truck darts right.
This happens all the way home. The next day, it drives fine again.

Any other time the truck drives straight and only has a slight pull to the right.

Could this be a brake or caliper issue?

I had the front end apart recently to paint my bare hubs as they were starting to rust a little. While I had the calipers out, I extended the brake pistion by applying the brake pedal, then pushed them back in with a C clamp. I did this one piston at a time, clamping the other three in place.
I haven't done this to the rear yet but plan on maybe this weekend.

Had a front end alignment done shortly after buying the truck last year. Mechanic checked out the front suspension and said all was good, no slop anywhere. Just a bad seal on the right side axle housing.

Any advice or things to inspect are greatly appreciated. I have a '73 K5 Blazer I built so I'm used to straight axle leaf spring trucks. It has no issues with death wobble at all.

 

It sounds like you’re driver front caliper/caliper bracket is seized. I experienced exactly what you are describing about 2 weeks ago. Have you checked the temp difference of one hub to the other after a drive? If one side is noticeably hotter than the other (i’m betting driver side), there you go

 

I havent checked it, but I will.

 

You just got me thinking.
after installing the front hubs, I took her on a road trip. When I stopped for lunch, I couldn't back up. My buddies and I started looking and found that the top caliper frame mounting bolt had come out. Every time I tried backing up, the whole assembly would tilt back and dig into the rim. I replaced the bolt with new ones and continued the trip.

It was some time after this that I started having issues. I'll have to check the bracket and make sure it's not bent.

 

Ok, just ordered a new bracket just in case the other one might have got bent. Easier to replace and have peace of mind than trying to figure out if its bent or not.

 

My guess is a seized caliper or gummed up bolts for the bracket. If the bolts become rusted or gummed up the caliper will not slide correctly. I too have dealt with this.

the death wobble which I have not experienced myself but witnessed another truck most likely will not pull to one side or the other. It will simply be uncontrollable due to the tires bouncing and we require immediately pulling to the side of the road as the only way to stop it is to stop the truck.

 

When I replace the bracket, my plan is to go thru each brake, cycle the pistons, and clean and relube all caliper pins.
thanks for your guys help.

 

Ok, time for an update.
got the new caliper mount and got time to install it today. Thru the front end up on the jack stands. Tried to rotate the wheel. Right side rotated, drivers side didnt.
Pulled everything off and drivers hub rotated fine. So something's binding. Took the caliper and did my c clamp trick and extended the pistons. Noticed one was hard to extend at first, and same thing when it got close to being back inside the caliper.
checked rotation as I put each piece back together and all was fine.
Applied the brakes a few times, then released and checked rotation. Drivers side would not budge but passenger was fine.
so it seems I have a bad piston in the caliper that jams up. Replaced the caliper, bleed the system and all checks good.
Took her on a road test and all is good. Notice too that as soon as I let off the brakes, she starts rolling.
Thanks for guiding me to the right area.
Maybe now I'll get some better MPG now that the brake is not dragging.

 

You should change calipers in pairs along with new flex hoses

 

Good point, could be the hose is delaminating. Happened to me on the rears a few years back with similar symptoms- the calipers seem to be binding but when you tear them apart there's nothing wrong.

 

Truck only has 130K miles on it.
It was just one of the pistons that was stuck. Probably got damaged somewhere along the way.
But I'll keep an eye on everything. I did flush out the fluid when I did new rotors and pads at 125K.
just needed to fix this issue. When I have more truck funds, I'll swap out the hoses to braided stainless steel and replace the other 3 calipers.