I recently bought an 83 K5 blazer. When driving it home I noticed a wobble that increased as my speed increased. I parked it at a friends house so I could get my father to pull it to my place. While I was waiting on him I decided to look it over real quick. Here's where the trouble shooting begins.

I noticed its in the front end while I was driving it so I got it in the air and grabbed the sides and top of the tires gave them some wiggle and shakes nothing felt wrong. I tried to spin the pass. front wheel and it was TIGHT so I pull the wheel off and notice the caliper is froze up. I was able to pry the pads off the rotor a bit and threw the wheel back on.

I then drove it and it still wobbles. I pull over (my father is behind me) and we hook the truck up. Now as Im being pulled (engine not running) when I look at my speedo were doing 40mph (made a point the chew on dad abit after seeing that) but I had NO wobble at all, but it still pulled to the right slightly. when I used the brakes the wobble never came back and I havent driven it since. Why would the wobble be gone when its in neutral and not running but when its moving under its own power it wobbles? The variables are engine off and in neutral. could it be a transmission mount loose? Or do any of you have a better idea?

I have ordered re-manufactured calipers, will have the rotors turned tuesday and im hoping this helps the issue, but doubtful.

 

Is it a 4x4 or a rear wheel drive? 4x4 engaged or off?

You mention that it does not do it when the engine is not running but you are being pulled. You may drive it until it does the wobble and put it in neutral let it coast and have the rpm drop to idle. If it goes away it could also be engine or transmission mounts.

To start with troubleshooting on the wheel side - do the "for free" stuff first:
Remove all the wheels, check the rims for cracks, bends, have a look at the center section where it contacts the hub. Remove debris, rust and such with a brush from the wheel as well as from the hub (brake disc).

As you are going to replace the calipers, remove them, remove the discs and check the meeting surface to the hub for debris, rust and such. Clean and check the hub itself.

Check the hubs appearance. I'm not sure but the K5 may still have adjustable bearings. Look for rust or rusty water coming out around the center nut. Should be not rust except for some light rusting of the casting itself. Clean the hub, check the bolts and their threads, check the discs.

Check the whole circumference and all of the sidewalls of all tires for wear, tear and damage. The wear will tell you how the trucks alignment and tire pressure was. Damage to tire and rim may indicate that the vehicle has hit something which can put it out of alignment and damage a bearing. Pump all tires to spec (include the spare wheel). You may want to consider new tires if keeping the truck. BTW: These fancy big tires on big rims account for many of the wheel and bearing problems encountered with these vehicles. The added leverage bigger wheel and tires exert on the bearings and suspension make things fail faster and if you hit something even lightly can bend things which would have withstood with the OEM wheels.

Once all is checked and well put the wheels back on and torque to spec with a little lube on the nuts (bolts). I use a high temp copper or silver paste sparingly on the contact surface of hub to disc and disc to wheel to avoid rust and seizing - "SPARINGLY"! Using high temp brake paste will avoid brake contamination - do not use grease or such on the disc or any brake part itself.

Check the wheel bearings. (12 and 6 o'clock position and rock - 9 and 3 o'clock position and rock - should have nearly no play at all). Turn the wheel by hand and feel it on the tire or rim. If the vehicle is supported you may want to grab a part of the suspension. If you turn the wheel now you can feel the bearing. There should be nothing to feel.

Now the free or nearly for free part is coming to an end. Depending on your equipment it still can be free. Else you have to go to a garage or a tire, better an alignment shop.

Check wheel run out. (Might be the rims - and have a look at the tires - bad cases can be identified by eye when turning the wheel by hand.
Wheel balancing. (Maybe the weights have fallen off)
Check run out of the brake discs.
Check all suspension components especially the knuckles and joints.
Check all steering joints and levers.
Check alignment. (Might be the reason it pulls to one side)
Check steering gearbox.

Give all joints with greasing points a shot with the grease gun and include the drive-shafts. Work with someone which can push the plastic or rubber sleeves down on the joints to have the grease go into the joint/bearing and continue until you see fresh grease come out. Wipe all excess off!

Good luck with troubleshooting

 

when i had the death wobble really bad on my 84 blazer it was due to unbalanced tires. also replace your steering stabilizer shock if its bad, get a dual shock stabilizer if you have bigger then 33 inch tires.

if you have manual hubs, turn your wheels all the way one way, lock the hub and spin the tires in the front with the truck off the ground. if it moves just a bit then stop your wheel joints are seized (the u-joint behind the front knuckle)

 

Error it is a 4x4, I haven't put it in neutral to after the wobble to see if it settles down I was going to check the motor/trans mounts while its in the drive way.

I can take it to my old school and have the tires/wheels balanced and checked for out of round ect. When I do that I can check over the all the steering and suspension components for looseness and wear. Ill tear the hub apart and check it over and replace or repack the bearing depending on results. Its running on factory spec tires but does have 2 shocks per wheel up front.

The only thing that I haven't seen/heard of is adjustable bearings. I'm sure Ill notice the difference when I have it apart. there may be some questions on that when I see them.

Thanks for the ideas Ill let yall know what happens

 

good luck that it may be a cheap one to solve!