After reading that it has over 200k, I would flush the brakelines, and put new in there. I had a 90 GMC that had 150k and the fluid looked like mud.
CK5
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Braking problem
- Thread starter bboyle
- Start date
RedBrute
1/2 ton status
After reading this post, I'm wondering if the problem may be a change in suspension geometry front to rear? Both axles must remain parallel to track straight, if you have worn bushings it may allow the axles to shift unevenly front to rear causing the "pull" to the right. A simple test would be to use the Ebrake to stop the truck. Putting all the force on the rear ought to show any bushing/mounting problems in the rear. the front may require plugging the rear line. Also... the prop valve is an "X" type??? wouldn't that require 2 separate hard lines and 2 flex lines at the rear? Not sure I believe the mechanic that said that. Good luck and welcome to CK5. If we can't fix it, no one can... ( I hope).
Pookster
1/2 ton status
I reanalyzed your problem with the extra information you have given me.
I believe your issue is acutally in your front springs. You still on your stock front springs?
I think you have a soft right passenger front- Take it for what its worth, Its better stated as "one of the springs is harder than the other".
your springs do more than just absorb bumps- they are also the axle positioner. Unfortunately, leaf spring design inherently has this as a characteristic- as it de-arches, it extends. Thats why the stock spring is so flat from the factory in the front! (minimum growth in length). (and also why so many people use trailing arms)
If either spring acts differently- whether it is one firmer or one softer, if the difference gets high, you will also get this effect.
Try this if you can - swap the springs from left to right. See if this changes things. Also check if the bushings are still intact.
I hate to see you give up on this truck - its been with you so long.
Just keep in mind- cross over steering would get rid of most of this issue. Its just a basic flaw of the pitman arm/ steering arm setup on our trucks.
I must have spent 1k on trying to diagonse my steering issues- in the end, none of them were really successful- and truthfully, it was because I lifted, added springs of variable rates that werent balanced (the fronts were stiffer than the flexy stock rear after being 20 years old, + a shackle flip changed the design aspect of the spring. ).
BTW, if your springs are old all around (say 20 years old) it is probably time to change em.
I believe your issue is acutally in your front springs. You still on your stock front springs?
I think you have a soft right passenger front- Take it for what its worth, Its better stated as "one of the springs is harder than the other".
your springs do more than just absorb bumps- they are also the axle positioner. Unfortunately, leaf spring design inherently has this as a characteristic- as it de-arches, it extends. Thats why the stock spring is so flat from the factory in the front! (minimum growth in length). (and also why so many people use trailing arms)
If either spring acts differently- whether it is one firmer or one softer, if the difference gets high, you will also get this effect.
Try this if you can - swap the springs from left to right. See if this changes things. Also check if the bushings are still intact.
I hate to see you give up on this truck - its been with you so long.
Just keep in mind- cross over steering would get rid of most of this issue. Its just a basic flaw of the pitman arm/ steering arm setup on our trucks.
I must have spent 1k on trying to diagonse my steering issues- in the end, none of them were really successful- and truthfully, it was because I lifted, added springs of variable rates that werent balanced (the fronts were stiffer than the flexy stock rear after being 20 years old, + a shackle flip changed the design aspect of the spring. ).
BTW, if your springs are old all around (say 20 years old) it is probably time to change em.
I haven't posted for a while because I had nothing new to report. The truck has been at the alignment shop for 16 straight days. The truck pulls to the right when braking more drastically than when it arrived 16 days ago. I remain totally baffled and have come to the conclusion that this shop and its crew of mechanics are not capable of fixing this brake problem.
Just to recap. Here's what has been done in chronological order, first to last done.
1. Front calipers installed along with new rubber hoses to each caliper (shop 1)
2. Another set of calipers installed (by Shopt 2 who has the truck)
3. Alignment performed so vehicle would track correctly; steering box adjusted to remove play. (tracking improved, steering feel was wrong though)
4. new combination valve/proportioning valve
replaced.
5. Back wheel cylinders double checked for leaks and proper operation
6. Rebuilt master cylinder installed
7. Steering box replaced with rebuilt unit; steering tension and return much improved over the worn out box
8. Left front hard brakeline fabricated and replaced (truck pull worsened with the new line and pulls so severely to the right the truck ran off the road when I test drove it. Worst pulling ever experienced. Truck is an accident waiting to happen in this condition)
9. It's my understanding a new fabricated right front hard brake line is now on the truck. I wasn't able to confirm this because the shopowner was not there this morning. However the pull is still there, I was told. It may be just as bad as reported in #8.
What the heck is wrong with this?
Just to recap. Here's what has been done in chronological order, first to last done.
1. Front calipers installed along with new rubber hoses to each caliper (shop 1)
2. Another set of calipers installed (by Shopt 2 who has the truck)
3. Alignment performed so vehicle would track correctly; steering box adjusted to remove play. (tracking improved, steering feel was wrong though)
4. new combination valve/proportioning valve
replaced.
5. Back wheel cylinders double checked for leaks and proper operation
6. Rebuilt master cylinder installed
7. Steering box replaced with rebuilt unit; steering tension and return much improved over the worn out box
8. Left front hard brakeline fabricated and replaced (truck pull worsened with the new line and pulls so severely to the right the truck ran off the road when I test drove it. Worst pulling ever experienced. Truck is an accident waiting to happen in this condition)
9. It's my understanding a new fabricated right front hard brake line is now on the truck. I wasn't able to confirm this because the shopowner was not there this morning. However the pull is still there, I was told. It may be just as bad as reported in #8.
What the heck is wrong with this?
surburban bus
Newbie
This might have already been done,but if not swich the tires around.Could have a bad tire.
It's been mentioned a few times already - it's a symptom of GM's design of the steering system. The front-to-rear draglink is easily influenced by axle movement, so ANY axle movement has an effect on the steering. One front spring softer than the other... one spring bushing deteriorated more than the others... one front brake that grabs just before the other... They all make the front axle move fore & aft under the frame, and the stock steering system is very sensitive to this.bboyle said:What the heck is wrong with this?
We (as in the CK5 community) have been over this issue repeatedly in the past 6-7 years - the only REAL cure for this condition is a swap to "crossover" steering, where the draglink is side-to-side. Axle movement has far less influence over this setup than the original GM design.
If it makes you feel any better, my '87 did it too... and if it were road-worthy, I'm sure it would still do it.
sandawgk5
3/4 ton status
jarheadk5 said:
That is the same thing I said back on post #7. Some people refuse to believe the factory would send out a product that is less than stellar
.Ira
G
goldwing2000
Guest
I have to concur with the suspension assessment. I would say almost definitely a front spring eye bushing, since the alignment shop would certainly have noticed a bad ball joint. If you replace them with poly bushings, it will limit the amount of compression during braking.
Alternately, it could be loose u-bolts or an elongated spring pin hole in the axle (usually the driver's side, as the passenger side is mounted to cast iron), as previously mentioned. Either of which could allow axle movement and since the left side of the axle is where the drag link connects, it will almost always pull to the right.
Oh, and looking down the side of the truck to visually align the front and rear wheels will never work out right, since the rear track is significantly narrower than the front track.
Alternately, it could be loose u-bolts or an elongated spring pin hole in the axle (usually the driver's side, as the passenger side is mounted to cast iron), as previously mentioned. Either of which could allow axle movement and since the left side of the axle is where the drag link connects, it will almost always pull to the right.
Oh, and looking down the side of the truck to visually align the front and rear wheels will never work out right, since the rear track is significantly narrower than the front track.
spring eyes..
I've seen several 4x4 GM's with the front leaf spring "eyes" opened up enough to allow the bushing to wallow around in it,or the spring is cracked where it wraps around the bushing --its often hidden by the "second" leaf ,which also wraps around the "main" leaf where the bushing goes..naturally,any lateral movement of the spring will make it pull,wander,or the brakes pull,since the axle is no longer paralell with the frame,and rear axle,it wont "track" right..
..
I've seen several 4x4 GM's with the front leaf spring "eyes" opened up enough to allow the bushing to wallow around in it,or the spring is cracked where it wraps around the bushing --its often hidden by the "second" leaf ,which also wraps around the "main" leaf where the bushing goes..naturally,any lateral movement of the spring will make it pull,wander,or the brakes pull,since the axle is no longer paralell with the frame,and rear axle,it wont "track" right..
..
