I have a 1985 GMC 1500 Sierra 1/2 ton 4WD with a few issues I can not diagnose.

1. Death Wobble - The truck has what I call a death wobble/bounce. The right front wheel start bouncing randomly so bad you would swear you are about to wreck out and die. A few weeks back i replaced the 4wd hubs and it went away. So, I figured that was it. However, yesterday at 35mph, it came back. It shakes the whole truck so bad it it unbelievable. As far as front end parts, I have had them checked and nothing is worn. What the heck is causing this (see next problem - may be related).

2. Brakes - I know for certain the rear passenger wheel cylinder is out. It leaks like crazy. Today, the pedal got very very hard and makes a heck of a hissing sound inside the cab. It was a hair low on fluid and I filled it. However, it's still hissing like crazy. Vacuum leak somewhere? Could the brake issue cause the sever wheel hop?

3. Blinkers - The turn signal indicators stay on 100% of the time when the headlights are on. Whats weird is, when the light switch is off, they do not stay on.

Any ideas guys?

Thanks.

 

The hissing sound is the brake booster gone bad. For your truck to be shaking that there has to be something worn out enough to notice just by checking everything. Who has checked it? I usually take mine to Firestone for a check. They usually have guys who know what they are doing. Im not sure bout the turn signals. May need a tech to check it out for ya.

 

I've had it to two techs and a couple shade tree mechanics. No front end parts appear worn in any way.

Could the brake booster going out make a brake grab and create a shake?

 

hey jason, i have the same year of pickup (the body anyways) and the rest is probably about the same. check your Steering Stabilizer. Mine was on the drivers side in front of the axle. they are about $40-65 depending on quality. it did the same thing with the shaking. like you felt like it was going to launch you out the window. it was terrible. but yeah try that. it just looks like a shock. if you take it off and its really sloppy and you can compress/decompress very easily its definitely worn. lemme know how it turns out!

 

Give us an update: what are you seeing on these issues right now?BTW, Going back to 0.8 would not probably help, as the factors that affect this are on the server as well as the client, and the servers have all long been updated.

 

The more I drive vehicles that dont have this featues, the more I really like it. I think a feature like this will be standard equipment or a common add-on for all new vehicles in the next 10 years.