Silver GT

I picked up and 89 pickup with an all pro 5" SAS and 5" all pro rear lift, locked front (lockrite), welded rear. 22re, 5spd, etc. for $1000 and drove it home! Needless to say it was a scary 2 mile ride. It was all over the road. Ive been fixing things here and there since i got it. One thing i noticed was when in 4wd with the hubs locked it vibrates BAD in the front, so i rebuilt the front axle, new wheel bearings, repacked everything with Green grease, and added the TG long spline kit to the front shaft (did myself). Well it STILL VIBRATES and it still all over the place!!! If i put it in 4wd with the hubs unlocked it doesnt vibe at all, only 4wd with hubs locked. It wanders all over the place no matter what. I put my angle finder on the flat part of the top steering arm and it read 10*, now there is already shims in the front (not sure what *) It should be 6*-8* correct?? I adjusted the toe already, 1/8" in. Now the vibe prob, what do you guys think of that? sorry for the long post, just wanted to be as detailed as possible.

waskillywabbit

iTrader: (-1)

all over the road? that is steering

vibrating? if it was the front axle it would do it in 2wd or 4wd

Please break out your issues as it sounds like you have several that are unrelated.

:wabbit2:

Silver GT

I know the two issues are unrelated, i was just putting it all out there.

I know the wandering is steering, I think its a caster problem but im not sure if im checking it right. Is it common for people to run shims with 5" springs on a SAS? I did a SAS in my old 94 pickup, 5" from TG and it drove just fine and straight as an arrow with no shims.

The vibration is whats really got me stumped, Wouldnt it not vibrate in 2wd because nothing but the wheel and hub is turning? But in 4wd everything is moving so would that cause a vibe when the axle shaft/diff turns? My pass front tire is cambered in also so my wheels look like this / | when you look at the front of the truck ( driver side is fine).
If i remember right though, It also doesnt vibe if in 2wd with the hubs locked.

This has got me stumped! (more the vibe than the steering)

Ol Hickory

Front drive line?

ScottyC

iTrader: (1)

How steep is the front driveshaft? I would guess that he put shims in the front because the driveline is too steep. Which is now causing the handling issues. However, without the shims the driveshaft angle is even worse.

Only real fix with that much lift is a High pinion front 3rd, or dual cases. Pick your poison.

HighLux

transfer case comes to mind for the vibration.....
all over the road makes me think idler arm.

Silver GT

I just installed TG 4.7:1 gears, and its got a SAS so not more idler arm.

Silver GT

If i remember right, the front driveshaft is 28* with the front drooped and doesnt bind. when i put my angle finder on the flat spot of the steering arm (top) it was 10* with the shim, should be 6-8* right?. would be more without the shim in there. Whats got me confused is my old truck had a 5" SAS with no shims and handled like a dream. Same exact set up with both trucks only this one is Allpro and the old one was TG.

dropzone

iTrader: (6)

sounds like a quality of the install issue....

Pics?

Silver GT

That wouldnt surprise me, I bought it like this. Ill try and get pics up in a few days. should be working on it wed. night. I should have just built my 93 like i was going to but i couldnt pass this truck up for $1000. I could part it out for more than that.

Ahbustae86

Is the front drive shaft an aftermarket with high angle cv's? I ordered one of those before and it was meant for slow offroad use only. I hardly ever run at a slow pace. My truck's front end shook like a salt shaker whenever I took it on the sand. The manufacture told me that the shaft wasn't meant for high speed because the shaft couldn't be balanced. Basically it was for crawling.

Silver GT

no, The shaft that was in it was home made with standard u joints both ends. The one in it now is also home made, unbalanced 85 front cv and TG long spline kit. Def smoother than the first shaft by far and it still doesnt bind at full droop.

Silver GT

I took some pics tonight.....











SITTING FLAT ON THE GROUND 24*




CASTER AFTER WITH NO SHIMS


NOT SURE WHATS UP WITH THE SHACKLES BUT I HAD TO TAKE OUT SPACERS AND PUT IN SOME WASHERS SO THEY ARE STRAIGHT, THEY WERE BOWED OUT REAL BAD WITH BOTH SPACERS.




FLAT ON THE GROUND AND 6*


THIS IS HOW IM MEASURING CASTER, IS THIS RIGHT OR WRONG???


FRONT PINION 6*




DROOPED ALL THE WAY OUT, ITS CLOSE BUT DOESNT HIT OR BIND






D SHAFT ANGLE 29* DROOPED




So tell me what you guys think. I adjusted the toe again, still 1/8" in and after i fixed the shackles it wanders less but still does it. One thing i noticed is that it turns REAL EASY, my 93 with 31s isnt this easy. Steering feels loose but everything is tight, even the box, could the box be bad inside?. Do you think a track bar would help this? Is it common to run them with a 5" SAS?

Thanks for all the input and replys, good or bad.

ScottyC

iTrader: (1)

Pics of shims?

Silver GT

I didnt get any. They only measured out to 1*, fat end towards the front. I took them out though.

84Horunner

Take your front driveshaft out, put in 4WD, lock hubs and see if it vibrates really bad. Then unlock hubs and drive around. That will let you know if its A. your driveshaft/angle to your diff (Which by the way looks a little much) B. Your front axle/steering something is out of whack. Thats my two pennies, and a few ideas to isolate your problem down to a few areas.

ScottyC

iTrader: (1)

Are the splines greased really well on the driveshaft and is it in phase?

Silver GT

Ya its in phase and greased with "green grease".

Ive had the truck out a few times now and doesnt seem too bad. I think all the vib is def the front shaft and the angle that its at. The steering isnt horrible, maybe im just getting use to it, but it does feel "loose". Now everything is tight/good, does my 89 use a slower ratio box? could it be worn out inside but show no play? Oh and im not running the steering dampner cuz it didnt come with one, would that make a big differance?

bezrq surf

the steering dampener would hide it, but i dont think it would fix it.

Silver GT

I just wanted to report back to this thread incase someone came across it while searching. (I hate dead end threads). The vibe issue was def the drive shaft angle. The "wandering" issue was mostly alignment issues and worn out steering box. Thanks to all that put in there 2 cents and tried to help me with this. I have cut this truck up and put all the SAS parts in my 89 runner with RUF and ALL of these issues are now gone!