Reply
 
Thread Tools Display Modes
 
Old 02-12-2019, 02:13 PM   #101
Silver Member
 
Join Date: Sep 2018
Location: quebec
Posts: 58
Default

Quote:
Originally Posted by booster View Post
If toed in 1/8" you would be OK with that looseness, I think.

The cross caster should make it pull left, the question is just how much. I know that at .3 or .4 higher on the right, our van just about holds straight on a right crown, and you have near double that so it may be contributing. Really hard to tell for sure if also have mismatched and way to much plus camber and toe. I would not get very concerned about most driving issues until you get the numbers reading right.

If they said they shouldn't move the cams, then your alignment changes from lifting over 2" weren't taken care of, and they do change. Do the cams even look like they were touched? How about the tie rod adjuster sleeves?

Checking for looseness with the wheels off the ground won't tell you much except for the ball joints, and even then it is not real accurate.
I did not check toe from front to back of tires. The steering linkage and other stuff are so low they come in conflict with my tape measurer. So I just took a measure with marks on the front side of tires as high from the ground as I could go without contacting with the linkage.(hope that's understandable)

About cams, he said he did not touch them. Not sure about tie rod adjuster sleeves. I have an appointment this friday for a recheck.
Are you saying that the cams are the only camber/caster adjustment ?
__________________

lejeep is offline   Reply With Quote
Old 02-13-2019, 02:39 PM   #102
Silver Member
 
Join Date: Sep 2018
Location: quebec
Posts: 58
Default

Quote:
Originally Posted by booster View Post
If toed in 1/8" you would be OK with that looseness, I think.

The cross caster should make it pull left, the question is just how much. I know that at .3 or .4 higher on the right, our van just about holds straight on a right crown, and you have near double that so it may be contributing. Really hard to tell for sure if also have mismatched and way to much plus camber and toe. I would not get very concerned about most driving issues until you get the numbers reading right.

If they said they shouldn't move the cams, then your alignment changes from lifting over 2" weren't taken care of, and they do change. Do the cams even look like they were touched? How about the tie rod adjuster sleeves?

Checking for looseness with the wheels off the ground won't tell you much except for the ball joints, and even then it is not real accurate.
Trying to prepare for this friday's alignement appointment.
From the pic, I would understand that +caster brings the wheel forward and that would result in (lifting) the wheel further up off the ground. If that is the case, do I understand that a higher wheel off the ground on the pass. side would make the van pull to the left ?

Also, if there is some loose in the steering linkage, would the sympthom be some play in the steering wheel ? I ask this one because as I said before I saw some play on the pitman and idler arms while the wheels were off the ground, but do not fell anything on the steering wheel.

Thanks again for your continuing support, I would be at a loss if it was not for this forum. Very apperciated and educational.
Attached Images
File Type: jpg Caster.jpg (137.8 KB, 0 views)
__________________

lejeep is offline   Reply With Quote
Old 02-13-2019, 04:49 PM   #103
Platinum Member
 
Join Date: Aug 2010
Location: Minnesota
Posts: 7,012
Default

Quote:
Originally Posted by lejeep View Post
Trying to prepare for this friday's alignement appointment.
From the pic, I would understand that +caster brings the wheel forward and that would result in (lifting) the wheel further up off the ground. If that is the case, do I understand that a higher wheel off the ground on the pass. side would make the van pull to the left ?

Also, if there is some loose in the steering linkage, would the sympthom be some play in the steering wheel ? I ask this one because as I said before I saw some play on the pitman and idler arms while the wheels were off the ground, but do not fell anything on the steering wheel.

Thanks again for your continuing support, I would be at a loss if it was not for this forum. Very apperciated and educational.

The wheel position is nearly completely set by the lower ball joint when straight ahead, so not anything to do with caster. Caster is just theoretical line through the two ball joints to the road surface. Caster is the distance from the line to centerline of the wheel on the ground. Positive caster is when that theoretical line hits the road in front of the line down from the wheel center. No lifting, or such. It is the same thing as a bicycle steering with caster angle being the angle of the front tube with the bearings in it. The further the wheel center, at the ground, is behind the caster line at the ground, the more centering and restoring force you get. That can give more directional stability. Mismatched caster gives more restoring force to one side over the other and can cause pulling.



Caster in a double A frame vehicle like these is adjusted by moving the upper balljoint to the front or rear. When they move the cams, they move that pivot point in or out and that moves the upper balljoint position and changes the caster.


Normally, you would feel looseness, but it can be deceptive sometimes when you might think you have none and you do have looseness, or the other way around. I prefer to have vehicle on the pavement, motor running, and move the wheel back and forth a small amount to see how much motion the steering wheel has to move before the wheels do. The motion on the pitman and idler arm would give a clue to if it would show up in driving. A little up and down isn't usually all that bad, but side to side is not good. IIRC, the pitman (attached to the steering gear) doesn't have a joint on it as the joint is on the bar it attaches to, so the pitman really couldn't need replacing if that was the case.


At the age of your van, depending on often it was greased, it is highly likely that some steering parts would need replacing, though. The parts are relatively cheap compared to the cost of getting and alignment afterward each time one is replaced, so it is often worth it to do most or all the joints and only have to buy one alignment.
booster is offline   Reply With Quote
Old 02-14-2019, 12:12 AM   #104
Silver Member
 
Join Date: Sep 2018
Location: quebec
Posts: 58
Default

Quote:
Originally Posted by booster View Post
The wheel position is nearly completely set by the lower ball joint when straight ahead, so not anything to do with caster. Caster is just theoretical line through the two ball joints to the road surface. Caster is the distance from the line to centerline of the wheel on the ground. Positive caster is when that theoretical line hits the road in front of the line down from the wheel center. No lifting, or such. It is the same thing as a bicycle steering with caster angle being the angle of the front tube with the bearings in it. The further the wheel center, at the ground, is behind the caster line at the ground, the more centering and restoring force you get. That can give more directional stability. Mismatched caster gives more restoring force to one side over the other and can cause pulling.

Caster in a double A frame vehicle like these is adjusted by moving the upper balljoint to the front or rear. When they move the cams, they move that pivot point in or out and that moves the upper balljoint position and changes the caster.

Normally, you would feel looseness, but it can be deceptive sometimes when you might think you have none and you do have looseness, or the other way around. I prefer to have vehicle on the pavement, motor running, and move the wheel back and forth a small amount to see how much motion the steering wheel has to move before the wheels do. The motion on the pitman and idler arm would give a clue to if it would show up in driving. A little up and down isn't usually all that bad, but side to side is not good. IIRC, the pitman (attached to the steering gear) doesn't have a joint on it as the joint is on the bar it attaches to, so the pitman really couldn't need replacing if that was the case.

At the age of your van, depending on often it was greased, it is highly likely that some steering parts would need replacing, though. The parts are relatively cheap compared to the cost of getting and alignment afterward each time one is replaced, so it is often worth it to do most or all the joints and only have to buy one alignment.
Ok I think I get it. So the lower ball joint is acting as a pivot point and the upper ball joint moves back and forth via the cams and that changes the caster.
Are those cams the only adjustment for caster and camber ?
I will do a linkage tightness check using your procedure before going for the alignement. Have to wait a bit, we had about 1 1/2 ' of snow last night.
About the pitman arm, I am sure I saw something loose there (wheels off the ground). It looked like a loose connection between the steering box output shaft and the pitman arm. I hope it's on the other end of the pitman arm. I don't want to replace a steering box for sure.
Thank you again for the explanation, very interesting.
lejeep is offline   Reply With Quote
Old 02-14-2019, 12:54 AM   #105
Platinum Member
 
Join Date: Aug 2010
Location: Minnesota
Posts: 7,012
Default

Quote:
Originally Posted by lejeep View Post
Ok I think I get it. So the lower ball joint is acting as a pivot point and the upper ball joint moves back and forth via the cams and that changes the caster.
Are those cams the only adjustment for caster and camber ?
I will do a linkage tightness check using your procedure before going for the alignement. Have to wait a bit, we had about 1 1/2 ' of snow last night.
About the pitman arm, I am sure I saw something loose there (wheels off the ground). It looked like a loose connection between the steering box output shaft and the pitman arm. I hope it's on the other end of the pitman arm. I don't want to replace a steering box for sure.
Thank you again for the explanation, very interesting.

Ride height changes will also change the caster and camber, but ride height is not used to set the caster or camber. The cams are the only thing used to set them.


If you have a loose steering box, it might be able to be adjusted with the adjusting bolt. Sometimes it works sometimes it doesn't.
booster is offline   Reply With Quote
Old 02-14-2019, 03:44 PM   #106
Silver Member
 
Join Date: Sep 2018
Location: quebec
Posts: 58
Default

Quote:
Originally Posted by markopolo View Post
I'll just add that lejeep's control arm etc. does not look like what in the '97 to '02 series van. There's some photos of my '97 in this topic: http://www.classbforum.com/forums/f8...ings-4136.html

1996 was the changeover year so I always refer to the series as 1997 - 2002. Some 1996 vans would be like the 1997 vans.

Something similar may have occurred in the latter part of 2002.

lejeep's van is most likely the newer 2003 style van and is a 2003 model year even if manufactured in late 2002.
Some thing slipped in my mind. I did not realize that 2002 and older did not have the 6,0l engine but the 5,7l. It just didn't click when Booster mentionned smaller engine block and possible engine compartment dimensions.
So I went to a gm parts website and did a comparable on front susp. components.(see pic)
It looks like most of the components are different because until 2002 all parts numbers are the same(most anyway). If I select 2003 and younger the numbers have mostly all changed.
That is most likely why the alignement specs also changed after 2002 IMO.
So now when I go back for the alignement recheck this friday I can tell the mechanic he has to pull the 2003-04 specs instead of the 96-02's if he does not want to use specific specs(like Booster's).
What saddens me is that after I tell the outfit what should be done for alignement with the proof I found, I will have contributed to the genegal dislike those outfits have about our vans and probably not be welcomed there again.
Attached Images
File Type: png 2003 vs 2002 susp components.png (227.1 KB, 5 views)
lejeep is offline   Reply With Quote
Old 02-14-2019, 03:51 PM   #107
Silver Member
 
Join Date: Sep 2018
Location: quebec
Posts: 58
Default

Quote:
Originally Posted by booster View Post
Ride height changes will also change the caster and camber, but ride height is not used to set the caster or camber. The cams are the only thing used to set them.

If you have a loose steering box, it might be able to be adjusted with the adjusting bolt. Sometimes it works sometimes it doesn't.
Thanks for the tip about steering box adjustment.

I suspect that most outfits just check toe as it is easy and most people do not change ride height. They go get an ''alignement'' because they hit a pot hole or something. So the outfit says alignement when in fact they mean toe adjustment.
Hey, what more do you want for just $100
lejeep is offline   Reply With Quote
Old 02-18-2019, 11:24 PM   #108
Silver Member
 
Join Date: Sep 2018
Location: quebec
Posts: 58
Thumbs up 2003 chevy roadtrek suspension mod completed

Ok folks,
I embarked on this thread at post no. 21. After what looks like a saga I accepted the finality of this project with a sweet/sour taste in my mouth.

I had decided to go the Moog 81004 coil springs and Air Lift Ultimate air bags for the front and rear respectively. If necessary, I would also replace the shocks for Bilstein or Munroes.

The sour taste;
To this day, I do not know what coil springs are installed and probably will never know. The installer strongly suggested he ordered all the parts and would give me the same price I had found on different websites. Fine I thought since he would take responsibility in delivery and product quality.

Well, I had to wait at least 2 weeks for the installer to recieve the springs and another week to schedule an appointment. Well what do you know, the springs are ''wrong in the box''. A good 2 more weeks to send back the ''wrong in the box'' and recieve new ones. This time the installer says they come directly from Moog ?
Second try, what do you know, ''wrong in the box'', AGAIN. The 81004 are supposed to be 17 3/4'' free length and have tangential ends (open ends) on both ends. What they installed is 17 1/2'' free length and tangential on one end and squared on the other. They seem to be 1,027'' thick, close enough to the specified 1,03''

Lucky for me, the installer did not say anything about messing up the lower ball joints on the first install. So I came prepared the second time with two new Moog lower ball joints, only to be told that one was missing the dust/grease boot.
Lucky again for me, the old ball joints had been replaced already with Moog's. So the installer saved one of the old boots and used it on the new one without telling me.

Lesson learned;
Even if the installer does not want you in the shop, INSIST on seeing and better yet identify and measure all your parts BEFORE you give the OK to the installer. Myself, I was pretty intimidated to ask questions while the work was being done. That would have been avoided by insisting on the BEFORE part of the deal. My bad.

The sweet taste;
A member mentionned to me that what was important was the end result, not the specifics of the job. Thanks Booster for supporting me all the way in this project.
Even though I did not get the right springs, I must say they do the job maybe even better than the 81004 because the squared end on one side is more like the originals that were in there. This squared end now sits against the rubber cap (on top) and is probably less prone to tear/puncture that cap than an open end coil would.

Surprisingly enough, the shocks seem to do the job OK I guess. Hit a bump or hole and it's a one / two thing and done. Maybe that will change once the van is loaded. They are probably originals and have 71900 miles on them, maybe ''soft miles''. They stay on for now.
Ground clearance and ride comfort have also improved with these springs.
So I told the installer about that and accepted to keep these coil springs as is. Wish I was a little bird sitting on the shop owner's shoulder right now...

The air bags were a charm. I did not go the compressor way figuring I will probably not play with clearance very much once it will be set. Although I am glad to have the convenience to beef up the rear if I ever want to tow my boat one day. There was one leak that seems to have dissapeared by itself. That was probably at a valve. I will keep monitoring but everything looks fine for now.

End results;
Height before suspension modification:
LF:34'' RF:34'' LR:35'' RR:35''
Height after mods:
LF: 36'' RF:35.5'' LR:36.5'' RR:36.5'' (rear air bags @ 35psi)

Comfort:
Ride is a bit harsher on bigger bumps that with original springs in front and sitting on overload in the rear, but is just as smooth on the highway or secondary roads. Will probably feel even better once loaded up for travel.

Steering:
There is some loose (about 3/16'' to 1/4'' total) at the pitman and idler arm that you can see if you put the front end off the ground and wiggle the wheels, but nothing once the wheels are on the ground.
With that in mind and after two alignement attemps (three actually as the first place I went, the outfit said it was not doable because of the loose parts), steering is acceptable but not perfect IMHO. The van does not wander and response is linear and predictive. Does not pull one way or the other but too neutral, again IMO. I guess a little more caster would help correct this (as Booster suggested).
Problem is, It's pretty hard to tell the outfit what to do for alignement. You are the customer and are not expected to interfere with the alignement outfit.

Final thoughts:
I would not have done this mod if it was not for this forum and all the people that pitched in. Thank you ALL.
Now that it's done, I would not want to go back to the original and I believe it is an investment for now;
better clearance = less scrapes and repairs underneath
better steering and overall control on the roads
possibility to aventually carry more in the rear, think rear rack or towing
and for the future;
just tell the future owner to shop around and check ground clearance, that should convince any sensible person of your higher van quality.

If I missed anything, please feel free to comment. Hope this rather long report will be usefull.
Happy trails to all.
Like Mr. Gump would say, ''life is like a box of chocolate, you never know what you are gonna get!''
lejeep is offline   Reply With Quote
Old 02-18-2019, 11:26 PM   #109
Silver Member
 
Join Date: Sep 2018
Location: quebec
Posts: 58
Default

Ooops, forgot to attach final alignement results.
Attached Images
File Type: jpg alignement final.JPG (200.6 KB, 4 views)
lejeep is offline   Reply With Quote
Old 02-19-2019, 12:12 AM   #110
Platinum Member
 
Join Date: Aug 2010
Location: Minnesota
Posts: 7,012
Default

Sounds like you are in pretty good shape. My guess would be if those are original shocks (they could have been replaced with OEM in the past) you will be looking for them fairly soon when you see windy and with a full load, but you never know.


I would keep an eye on the outside edges of the front tires as the camber is a bit high, but may if it doesn't show shoulder wear not an issue, as it will help tracking a bit, I think.


You front height is not really much off at all, especially if you are lightly loaded. If it was 36" both sides you might be a bit high, but with 35.5" on the RF, the 35.75" average is pretty normal and will likely settle a 1/4 inch.



There is some kind of a bias in nearly all of the Chevies that makes the LR run low even unloaded stock. When you get in a loaded up B, it depends on where the weight is and could also be the RF low like you see. Basically, they appeared to take change the rear spring location or rate on the left side so it is a bit higher on the frame, which takes weight off it and makes that side run a bit low. Top theory, IMO, is that they did it to move weight from the RR to LR so the RR tire isn't overloaded when at max axle weight. What they call "wedge" in Nascar terms.



You might want to try running a bit different air pressures to see if the front goes even side to side and then see if drives differently, it may or may not change enough to notice. Yours is actually opposite of what most are in unevenness so it may also settle in over time and with normal loading, especially full tank of gas which is in the left rear.


All in all, I think it will be much more enjoyable to drive now, and less tiring on long days.
__________________

booster is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 10:54 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.